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Background: Soft tissue balancing in TKA has traditionally relied on surgeons' subjective tactile feedback. Although sensor-guided balancing devices have been proposed to provide more objective feedback, it is unclear whether their use improves patient outcomes.Questions/purposes: We conducted a randomized controlled trial (RCT) comparing freehand balancing with the use of a sensor-guided balancing device and evaluated (1) knee ROM, (2) patient-reported outcome measures (PROMs) (SF-12, WOMAC, and Knee Society Functional Scores [KSFS]), and (3) various surgical and hospital parameters (such as operative time, length of stay [LOS], and surgical complications) at a minimum of 2 years of follow-up.Methods: A total of 152 patients scheduled for primary TKA were recruited and provided informed consent to participate in this this study. Of these, 22 patients were excluded preoperatively, intraoperatively, or postoperatively due to patient request, surgery cancellation, anatomical exclusion criteria determined during surgery, technical issues with the sensor device, or loss to follow-up. After the minimum 2-year follow-up was accounted for, there were 63 sensor-guided and 67 freehand patients, for a total of 130 patients undergoing primary TKA for osteoarthritis. The procedures were performed by one of three fellowship-trained arthroplasty surgeons (RPS, HJC, JAG) and were randomized to either soft tissue balancing via a freehand technique or with a sensor-guided balancing device at one institution from December 2017 to December 2018. There was no difference in the mean age (72 ± 8 years versus 70 ± 9 years, mean difference 2; p = 0.11), BMI (30 ± 6 kg/m 2 versus 29 ± 6 kg/m 2 , mean difference 1; p = 0.83), gender (79% women versus 70% women; p = 0.22), and American Society of Anesthesiology score (2 ± 1 versus 2 ± 1, mean difference 0; p = 0.92) between the sensor-guided and freehand groups, respectively. For both groups, soft tissue balancing was performed after all bony cuts were completed and trial components inserted, with the primary difference in technique being the ability to quantify the intercompartmental balance using the trial tibial insert embedded with a wireless sensor in the sensor-guided cohort. Implant manufacturers were not standardized. Primary outcomes were knee ROM and PROMs at 3 months, 1 year, and 2 years. Secondary outcomes included pain level evaluated by the VAS, opioid consumption, inpatient physical therapy performance, LOS, discharge disposition, surgical complications, and reoperations.Results: There was no difference in the mean knee ROM at 3 months, 1 year, and 2 years postoperatively between the sensor-guided cohort (113° ± 11°, 119° ± 13°, and 116° ± 12°, respectively) and the freehand cohort (116° ± 13° [p = 0.36], 117° ± 13° [p = 0.41], and 117° ± 12° [p = 0.87], respectively). There was no difference in SF-12 physical, SF-12 mental, WOMAC pain, WOMAC stiffness, WOMAC function, and KSFS scores between the cohorts at 3 months, 1 year, and 2 years postoperatively. The mean operative time in the sensor-guided cohort was longer than that in the freehand cohort (107 ± 0.02 versus 84 ± 0.04 minutes, mean difference = 23 minutes; p = 0.008), but there were no differences in LOS, physical therapy performance, VAS pain scores, opioid consumption, discharge disposition, surgical complications, or percentages of patients in each group who underwent reoperation.Conclusion: This RCT demonstrated that at 2 years postoperatively, the use of a sensor-balancing device for soft tissue balancing in TKA did not confer any additional benefit in terms of knee ROM, PROMs, and clinical outcomes. Given the significantly increased operative time and costs associated with the use of a sensor-balancing device, we recommend against its routine use in clinical practice by experienced surgeons.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Knotted and knotless single-anchor reconstruction techniques are frequently performed to reconstruct full-thickness tears of the upper portion of subscapularis tendon. However, it is unclear whether one technique is superior to the other.Questions/purposes: (1) When comparing knotless and knotted single-anchor reconstruction techniques in full-thickness tears of the upper subscapularis tendon, is there a difference in stiffness under cyclic load? (2) Are there differences in cyclic gapping between knotless and knotted reconstructions? (3) Are there differences in the maximal stiffness, yield load, and ultimate load to failure? (4) What are the modes of failure of knotless and knotted reconstruction techniques?Methods: Eight matched pairs of human cadaveric shoulders were dissected, and a full-thickness tear of the subscapularis tendon (Grade 3 according to the Fox and Romeo classification) was created. The cadavers all were male specimens, with a median (range) age of 69 years (61 to 75). Before biomechanical evaluation, the specimens were randomized into two equal reconstruction groups: knotless single anchor and knotted single anchor. All surgical procedures were performed by a single orthopaedic surgeon who subspecializes in sports orthopedics and shoulder surgery. With a customized set up that was integrated in a dynamic material testing machine, the humeri were consecutively loaded from 10 N to 60 N, from 10 N to 100 N, and from 10 N to 180 N for 50 cycles. Furthermore, the gapping behavior of the tear was analyzed using a video tracking system. Finally, the stiffness, gapping, maximal stiffness, yield loads, and maximum failure loads of both reconstruction groups were statistically analyzed. Failure was defined as retearing of the reconstructed gap threshold due to rupture of the tendon and/or failure of the knots or anchors. After biomechanical testing, bone quality was measured at the footprint of the subscapularis using microCT in all specimens. Bone quality was equal between both groups. To detect a minimum 0.15-mm difference in gap formation between the two repair techniques (with a 5% level of significance; α = 0.05), eight matched pairs (n = 16 in total) were calculated as necessary to achieve a power of at least 90%.Results: The first study question can be answered as follows: for stiffness under cyclic load, there were no differences with the numbers available between the knotted and knotless groups at load stages of 10 N to 60 N (32.7 ± 3.5 N/mm versus 34.2 ± 5.6 N/mm, mean difference 1.5 N/mm [95% CI -6.43 to 3.33]; p = 0.55), 10 N to 100 N (45.0 ± 4.8 N/mm versus 45.2 ± 6.0 N/mm, mean difference 0.2 N/mm [95% CI -5.74 to 6.04]; p = 0.95), and 10 N to 180 N (58.2 ± 10.6 N/mm versus 55.2 ± 4.7 N/mm, mean difference 3 N/mm [95% CI -5.84 to 11.79]; p = 0.48). In relation to the second research question, the following results emerged: For cyclic gapping, there were no differences between the knotted and knotless groups at any load levels. The present study was able to show the following with regard to the third research question: Between knotted and knotless repairs, there were no differences in maximal load stiffness (45.3 ± 8.6 N/mm versus 43.5 ± 10.2 N/mm, mean difference 1.8 [95% CI -11.78 to 8.23]; p = 0.71), yield load (425.1 ± 251.4 N versus 379.0 ± 169.4 N, mean difference 46.1 [95% CI -276.02 to 183.72]; p = 0.67), and failure load (521.1 ± 266.2 N versus 475.8 ± 183.3 N, mean difference 45.3 [95% CI -290.42 to 199.79]; p = 0.69). Regarding the fourth question concerning the failure modes, in the knotted repairs, the anchor tore from the bone in 2 of 8, the suture tore from the tendon in 6 of 8, and no suture slipped from the eyelet; in the knotless repairs, the anchor tore from the bone in 2 of 8, the suture tore from the tendon in 3 of 8, and the threads slipped from the eyelet in 3 of 8.Conclusion: With the numbers available, we found no differences between single-anchor knotless and knotted reconstruction techniques used to repair full-thickness tears of the upper portion of subscapularis tendon.Clinical Relevance: The reconstruction techniques we analyzed showed no differences in terms of their primary stability and biomechanical properties at the time of initial repair and with the numbers available. In view of these experimental results, it would be useful to conduct a clinical study in the future to verify the translationality of the experimental data of the present study. [ABSTRACT FROM AUTHOR]

Background: Femoroacetabular impingement (FAI) is a recognized cause of hip pain and decreased quality of life and has been linked to primary idiopathic hip osteoarthritis (OA). Although the operative indications for FAI have expanded to include older patients, we do not know whether there is an increased risk of conversion to THA after femoroacetabular osteoplasty (FAO) via the mini-open approach for FAI in patients older than 40 years compared with younger patients, after controlling for other confounding variables.Questions/purposes: (1) After matching for gender, BMI, preoperative symptomatic period, surgeon experience, Tönnis grade, and degree of chondral lesion, are patients older than 40 years who undergo FAO for FAI more likely to be revised to THA at a minimum of 2 years' follow-up than are patients younger than 40? (2) Is there a difference in delta (postoperative minus preoperative) improvement in functional outcome scores in those patients who did not go on to THA between patients older than and younger than 40 years?Methods: Between 2003 and 2017, one surgeon performed 281 FAOs via the mini-open approach in patients older than 40 years and 544 of the same procedure in patients younger than 40 years. During that period, the general indications for FAO were the same in both age groups: (1) history and physical exam consistent with FAI, (2) radiographic evidence of focal impingement (cam, pincer, or both), (3) evidence of labral or chondrolabral tears, and (4) minimal to no arthritic changes (all four criteria required). In general, age was not used as a contraindication for surgery. A total of 86% (241 of 281) of patients older than 40 and 91% (494 of 544) of those younger than 40 were available for minimum of 2 years' follow-up, had complete datasets (radiographs as well as preoperative and most recent patient-reported outcomes scores) at a minimum of 2 years after surgery, and were considered eligible for the match. Propensity score matching was used to match for BMI, gender, preoperative symptomatic period, surgeon experience, Tönnis grade, and degree of intraoperative chondral lesion. We matched at a 1:2 ratio 130 patients older than age 40 with 260 patients younger than age 40. The mean ± SD follow-up duration for both groups was 5 ± 2 years. The mean age of the cohort of interest was 47 ± 5 years compared with 28 ± 7 years in the control. Fifty-four percent (70 of 130) of patients older than 40 years were women and 46% (60 of 130) were men; for those younger than 40, 51% (133 of 260) of participants were women and 49% (127 of 260) were men. Tönnis grade distribution for patients older than 40 was as follows: 46% (60 of 130) had Grade 0, 42% (55 of 130) had Grade 1, and 12% (15 of 130) had Grade 2. In comparison, Tönnis grade for patients younger than 40 was as follows: 52% (136 of 260) had Grade 0, 38% (100 of 260) had Grade 1, and 9% (24 of 260) had Grade 2 (p = 0.49). Chondral lesion degree was determined intraoperatively as none, a partial-thickness tear, or a full-thickness tear. Tönnis grade was determined based on preoperative plain AP hip radiographs. We then compared the percentage of patients who converted to THA during the surveillance period (our primary study outcome). We also compared the difference in delta (preoperative minus postoperative) improvement in functional outcome scores using the modified Harris Hip Score (mHHS) between the groups, excluding those who had already been converted to THA.Results: In patients older than 40 years, 16% (21 of 130) converted to THA at a mean time to conversion of 2 ± 1 years compared with 7% (17 of 260) at a mean time of 2 ± 2 years in patients younger than 40 years (p = 0.01). At a mean of 5 ± 2 years after FAO, among those patients who had not undergone conversion to THA, the mean delta mHHS score for patients older than 40 was 11 ± 17, compared with 20 ± 26 for patients younger than 40 (p = 0.04).Conclusion: Since approximately 1 in 6 patients older than 40 years in this series who underwent FAO for FAI opted for early conversion to THA at a mean time of 2 years after the osteoplasty procedure, and the remaining patients who did not undergo THA reported lower improvement in functional outcomes, we recommend surgeons avoid this procedure in patients in this age group until or unless we can better refine our indications. This is especially true because loss to follow-up causes us to believe that, if anything, our estimates of the risk of conversion to THA are conservative.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Classifying hips with structural deformity on the spectrum from impingement to dysplasia is often subjective and frequently inexact. Currently used radiographic measures may inaccurately predict a hip's morphological stability in borderline hips. A recently described radiographic measure, the Femoro-Epiphyseal Acetabular Roof (FEAR) index, has demonstrated an ability to predict stability in the borderline hip. This measure is attractive to clinicians because procedures can be used on the basis of a hip's pathomechanics. This study was designed to further validate and characterize the FEAR index in a skeletally immature population, in hips with dysplasia/femoroacetabular impingement (FAI), and in asymptomatic hips.Questions/purposes: (1) What are the characteristics of the FEAR index in children and how does the index change with skeletal maturation? (2) How does the FEAR index correlate with clinical diagnosis and surgical treatment in a large cohort of symptomatic hips and asymptomatic controls? (3) How does the FEAR index correlate with clinical diagnosis in the borderline hip (lateral center-edge angle [LCEA] 20°-25°) group?Methods: A total of 220 participants with symptomatic investigational hips with a clinical diagnosis of dysplasia or FAI between January 2008 and January 2018 were retrospectively collected from the senior author's practice. Investigational hips were excluded if they had any femoral head abnormalities preventing LCEA measurement (for example, Perthes disease), Tönnis osteoarthritis grade greater than 1, prior hip surgery, or prior femoral osteotomy. In the 220 participants, 395 hips met inclusion criteria. Once exclusion criteria were applied, 15 hips were excluded due to prior hip surgery or prior femoral osteotomy, and 12 hips were excluded due to femoral head deformity. A single hip was then randomly selected from each participant, resulting in 206 investigational hips with a mean age of 13 ± 3 years. Between January 2017 and December 2017, 70 asymptomatic control participants were retrospectively collected from the senior author's institutional trauma database. Control hips were included if the AP pelvis film had the coccyx centered over the pubic symphysis and within 1 to 3 cm of the superior aspect of the symphysis. Control hips were excluded if there was any fracture to the pelvis or ipsilateral femur or the participant had prior hip/pelvis surgery. After exclusion criteria were applied, 16 hips were excluded due to fracture. One hip was then randomly selected from each participant, resulting in 65 control hips with a mean age of 16 ± 8 years. Standardized standing AP pelvis radiographs were used to measure the FEAR index, LCEA, and Tönnis angle in the investigational cohort. Standardized false-profile radiographs were used to measure the anterior center-edge angle (ACEA) in the investigational cohort. Two blinded investigators measured the FEAR index with an intraclass correlation coefficient of 0.92 [95% CI 0.84 to 0.96]. Question 1 was answered by comparing the above radiographic measures in age subgroups (childhood: younger than 10 years; adolescence: 10 to 14 years old; maturity: older than 14 years) of dysplastic, FAI, and control hips. Question 2 was answered by comparing the radiographic measures in all dysplastic, FAI, control hips, and a subgroup of operatively or nonoperatively managed dysplasia and FAI hips. Question 3 was answered by comparing the radiographic measures in borderline (LCEA 20°-25°) dysplastic, FAI, and control hips.Results: The FEAR index was lower in older dysplastic of hips (younger than 10 years, 6° ± 9°; 10 to 14 years, 4° ± 10°; older than 14 years, 5° ± 9°; p < 0.001) and control hips (younger than 10 years, -6° ± 5°; 10 to 14 years, -15° ± 4°; older than 14 years, -16° ± 7°; p < 0.001). The diagnosis and age groups were independently correlated with the FEAR index (p < 0.001). The relationship between the FEAR index and diagnosis remained consistent in each age group (p = 0.11). The FEAR index was higher in all dysplastic hips (mean 5° ± 10°) than in asymptomatic controls (mean -13° ± 7°; p < 0.001) and FAI hips (mean -10° ± 11°; p < 0.001). Using -1.3° as a cutoff for FAI/control hips and dysplastic hips, 81% (112 of 139) of hips with values below this threshold were FAI/control, and 89% (117 of 132) of hips with values above -1.3° were dysplastic. The receiver operator characteristics area under the curve (ROC-AUC) was 0.91. Similarly, the FEAR index was higher in borderline dysplastic hips than in both asymptomatic borderline controls (p < 0.001) and borderline FAI hips (p < 0.001). Eighty-nine percent (33 of 37) of hips with values below this threshold were FAI/control, and 90% (37 of 41) of hips with values above -1.3° were dysplastic. The ROC-AUC for borderline hips was 0.86.Conclusion: The FEAR index was associated with the diagnosis of hip dysplasia and FAI in a patient cohort with a wide age range and with varying degrees of acetabular deformity. Specifically, a FEAR index greater than -1.3° is associated with a dysplastic hip and a FEAR index less than -1.3° is associated with a hip displaying FAI. Using this reliable, developmentally based radiographic measure may help hip preservation surgeons establish a correct diagnosis and more appropriately guide treatment.Level Of Evidence Level: III, diagnostic study. [ABSTRACT FROM AUTHOR]

Background: Although femoral retroversion has been linked to the onset of slipped capital femoral epiphysis (SCFE), and may result from a rotation of the femoral epiphysis around the epiphyseal tubercle leading to femoral retroversion, femoral version has rarely been described in patients with SCFE. Furthermore, the prevalence of actual femoral retroversion and the effect of different measurement methods on femoral version angles has yet to be studied in SCFE.Questions/purposes: (1) Do femoral version and the prevalence of femoral retroversion differ between hips with SCFE and the asymptomatic contralateral side? (2) How do the mean femoral version angles and the prevalence of femoral retroversion change depending on the measurement method used? (3) What is the interobserver reliability and intraobserver reproducibility of these measurement methods?Methods: For this retrospective, controlled, single-center study, we reviewed our institutional database for patients who were treated for unilateral SCFE and who had undergone a pelvic CT scan. During the period in question, the general indication for obtaining a CT scan was to define the surgical strategy based on the assessment of deformity severity in patients with newly diagnosed SCFE or with previous in situ fixation. After applying prespecified inclusion and exclusion criteria, we included 79 patients. The mean age was 15 ± 4 years, 48% (38 of 79) of the patients were male, and 56% (44 of 79) were obese (defined as a BMI > 95th percentile (mean BMI 34 ± 9 kg/m2). One radiology resident (6 years of experience) measured femoral version of the entire study group using five different methods. Femoral neck version was measured as the orientation of the femoral neck. Further measurement methods included the femoral head's center and differed regarding the level of landmarks for the proximal femoral reference axis. From proximal to distal, this included the most-proximal methods (Lee et al. and Reikerås et al.) and most-distal methods (Tomczak et al. and Murphy et al.). Most proximally (Lee et al. method), we used the most cephalic junction of the greater trochanter as the landmark and, most distally, we used the center base of the femoral neck superior to the lesser trochanter (Murphy et al.). The orientation of the distal femoral condyles served as the distal reference axis for all five measurement methods. All five methods were compared side-by-side (involved versus uninvolved hip), and comparisons among all five methods were performed using paired t-tests. The prevalence of femoral retroversion (< 0°) was compared using a chi-square test. A subset of patients was measured twice by the first observer and by a second orthopaedic resident (2 years of experience) to assess intraobserver reproducibility and interobserver reliability; for this assessment, we used intraclass correlation coefficients.Results: The mean femoral neck version was lower in hips with SCFE than in the contralateral side (-2° ± 13° versus 7° ± 11°; p < 0.001). This yielded a mean side-by side difference of -8° ± 11° (95% CI -11° to -6°; p < 0.001) and a higher prevalence of femoral retroversion in hips with SCFE (58% [95% CI 47% to 69%]; p < 0.001) than on the contralateral side (29% [95% CI 19% to 39%]). These differences between hips with SCFE and the contralateral side were higher and ranged from -17° ± 11° (95% CI -20° to -15°; p < 0.001) based on the method of Tomczak et al. to -22° ± 13° (95% CI -25° to -19°; p < 0.001) according to the method of Murphy et al. The mean overall femoral version angles increased for hips with SCFE using more-distal landmarks compared with more-proximal landmarks. The prevalence of femoral retroversion was higher in hips with SCFE for the proximal methods of Lee et al. and Reikerås et al. (91% [95% CI 85% to 97%] and 84% [95% CI 76% to 92%], respectively) than for the distal measurement methods of Tomczak et al. and Murphy et al. (47% [95% CI 36% to 58%] and 60% [95% CI 49% to 71%], respectively [all p < 0.001]). We detected mean differences ranging from -19° to 4° (all p < 0.005) for 8 of 10 pairwise comparisons in hips with SCFE. Among these, the greatest differences were between the most-proximal methods and the more-distal methods, with a mean difference of -19° ± 7° (95% CI -21° to -18°; p < 0.001), comparing the methods of Lee et al. and Tomczak et al. In hips with SCFE, we found excellent agreement (intraclass correlation coefficient [ICC] > 0.80) for intraobserver reproducibility (reader 1, ICC 0.93 to 0.96) and interobserver reliability (ICC 0.95 to 0.98) for all five measurement methods. Analogously, we found excellent agreement (ICC > 0.80) for intraobserver reproducibility (reader 1, range 0.91 to 0.96) and interobserver reliability (range 0.89 to 0.98) for all five measurement methods in healthy contralateral hips.Conclusion: We showed that femoral neck version is asymmetrically decreased in unilateral SCFE, and that differences increase when including the femoral head's center. Thus, to assess the full extent of an SCFE deformity, femoral version measurements should consider the position of the displaced epiphysis. The prevalence of femoral retroversion was high in patients with SCFE and increased when using proximal anatomic landmarks. Since the range of femoral version angles was wide, femoral version cannot be predicted in a given hip and must be assessed individually. Based on these findings, we believe it is worthwhile to add evaluation of femoral version to the diagnostic workup of children with SCFE. Doing so may better inform surgeons as they contemplate when to use isolated offset correction or to perform an additional femoral osteotomy for SCFE correction based on the severity of the slip and the rotational deformity. To facilitate communication among physicians and for the design of future studies, we recommend consistently reporting the applied measurement technique.Level Of Evidence: Level III, prognostic study. [ABSTRACT FROM AUTHOR]

Background: Short-length stems were developed to reduce bone loss of the proximal femur and potentially decrease the incidence of thigh pain after cementless THA. However, it remains unknown whether short stems indeed reduce bone loss or the frequency of thigh pain.Questions/purposes: Is there a difference between short- and standard-length stems in terms of: (1) the frequency or severity of thigh pain, (2) modified Harris hip scores, (3) implant loosening, or (4) bone mineral density as measured by dual-energy x-ray absorptiometry?Methods: Between March 2013 and January 2014, three surgeons performed 205 primary THAs. To be eligible, patients needed to be at least 20 years of age, have not undergone previous history of hip surgery, and have no metabolic bone disease. A total of 100 patients were randomized to receive THA either with a short stem (n = 56) or with a standard-length stem (n = 44). Both stems were proximally coated, tapered, cementless stems. Compared with standard stems, short stems typically were 30- to 35-mm shorter. A total of 73% (41 of 56) and 77% (34 of 44) of those groups, respectively, were accounted for at a minimum of 5 years and were analyzed. The presence of thigh pain during activity was evaluated using a 10-point VAS, and the modified Harris hip score was calculated by research assistants who were blinded to the treatment groups. Plain radiographs were taken at 6 weeks, 6 months, and 12 months postoperatively, and every 1 year thereafter; loosening was defined as subsidence > 3 mm or a position change > 3° on serial radiographs. Radiological assessment was performed by two researchers who did not participate in the surgery and follow-up evaluations. Bone mineral density of the proximal femur was measured using dual-energy x-ray absorptiometry at 4 days, 1 year, 2 years, and 5 years postoperatively. The primary endpoint of our study was the incidence of thigh pain during 5-year follow-up. Our study was powered at 80% to detect a 10% difference in the proportion of patients reporting thigh pain at the level of 0.05.Results: With the numbers available, we found no difference between the groups in the proportion of patients with thigh pain; 16% (9 of 56) of patients in the short-stem group and 14% (6 of 44) of patients in the standard-stem group experienced thigh pain during the follow-up period (p = 0.79). In all patients, the pain was mild or moderate (VAS score of 4 or 6 points). Among the 15 available patients who reported thigh pain, there was no difference between the implant groups in mean severity of thigh pain (4.3 ± 0.8 versus 4.2 ± 0.7; p = 0.78). There were no between-group differences in the short versus standard-length stem groups in terms of mean modified Harris hip score by 5 years after surgery (89 ± 13 versus 95 ± 7 points; p = 0.06). No implant was loose and no hip underwent revision in either group. Patients in the short-stem group showed a slightly smaller decrease in bone mineral density in Gruen Zones 2, 3, and 5 than those in the standard-stem group did; the magnitude of the difference seems unlikely to be clinically important.Conclusion: We found no clinically important differences (and few differences overall) between short and standard-length THA stems 5 years after surgery in a randomized trial. Consequently, we recommend that clinicians use standard-length stems in general practice because standard-length stems have a much longer published track record in other studies, and short stems can expose patients to the uncertainty associated with novelty, without any apparent offsetting benefit.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Ankle instability is common and previous studies have documented greater than 85% good-to-excellent outcomes based upon both patient-reported outcome measures and subjective evaluation of ability to return to previous activity levels after lateral ankle stabilization in the civilian population. However, patient-reported outcomes and performance may differ in the military population. The military oftentimes requires servicemembers to navigate uneven terrain and ladderwells, which can stress ankles differently than in their civilian counterparts. There has been limited evidence regarding patient outcomes after lateral ankle stabilization within a military population and its elucidation is important in optimizing outcomes for our servicemembers. Furthermore, the potential benefit of fibular periosteum augmentation with lateral ankle stabilization procedures in a military population has not been described. The results of using this extra tissue to reinforce the repair are important in determining whether its routine incorporation is indicated in the military.Questions/purposes: In an active-duty military population, we asked: (1) What proportion of patients who underwent lateral ankle stabilization using anatomic repair techniques with or without fibular periosteum augmentation achieved good-to-excellent outcomes based on the Foot and Ankle Disability Index (FADI) score at a minimum follow-up interval of 2 years? (2) Was the proportion of patients who achieved a good-to-excellent FADI score higher among those treated with fibular periosteum augmentation than those treated without? (3) Did the likelihood of achieving a good-to-excellent outcome after lateral ankle stabilization vary based on whether the procedure was performed by a fellowship-trained sports or foot and ankle orthopaedic surgeon versus a podiatrist?Methods: Between 2007 and 2017, 15 surgeons (six orthopaedic surgeons and nine podiatrists) performed 502 lateral ankle stabilizations. We excluded 4% (18 of 502) of patients because they were not active-duty at the time of surgery, and we excluded 12% (56 of 502) of lateral ankle stabilizations because they were performed as part of other potentially confounding foot or ankle procedures. We considered 60% (303 of 502) as lost to follow-up because the patients could not be contacted at least 2 years after surgery, they declined to participate, or they did not fully answer the questionnaires. This left 125 patients for analysis. Of those, 79% (99 of 125) had a procedure with fibular periosteum augmentation and 21% (26 of 125) had a procedure without augmentation. During the study period, five fellowship-trained orthopaedic foot and ankle surgeons and two podiatrists always used fibular periosteum augmentation. Orthopaedic surgeons performed 75% (94 of 125) of the procedures, and the other 25% (31 of 125) were performed by podiatrists. Whether a servicemember was treated by one specialty or the other was simply based upon whom they were referred to for care. Orthopaedic surgeons tended to perform procedures with augmentation (five with versus one without) and podiatrists tended to perform procedures without augmentation (two with versus seven without). To help account for this confounding factor, we performed separate analyses for procedures performed with versus without augmentation in addition to procedures performed by orthopaedic surgeons versus podiatrists. We retrospectively contacted each patient to obtain their self-reported overall result, FADI outcome score, and postoperative military capabilities. The minimum follow-up duration was 2 years; overall mean follow-up duration was 7 years. The fibular periosteum augmentation group mean follow-up was 7 ± 4 years and without augmentation was 6 ± 3 years. The orthopaedic surgeons group mean follow-up was 7 ± 3 years and the podiatrists group was 7 ± 3 years. We obtained postoperative FADI scores via phone interview along with data regarding the patients' postoperative military capabilities, but did not have preoperative FADI scores.Results: Pooling both surgical treatments, 67% (84 of 125) of the patients reported good-to-excellent results and 33% (41 of 125) reported very poor-to-fair results. We found no difference in the proportion of patients treated with fibular periosteal augmentation who achieved a good or excellent score on the FADI than was observed among the patients treated without periosteal augmentation (68% [67 of 99] versus 65% [17 of 26]; odds ratio 1 [95% CI 0 to 2]; p = 0.81). The proportion of patients who achieved a good or excellent score on the FADI did not differ depending on whether the procedure was performed by an orthopaedic surgeon or a podiatric surgeon (66% [62 of 94] versus 71% [22 of 31]; OR 1 [95% CI 1 to 2]; p = 0.66).Conclusion: The patient-reported outcome scores after lateral ankle stabilization in our study of military servicemembers at a minimum of 2 years and a mean of 7 years were far lower than have been reported in studies on civilians. Indeed, our findings may represent a best-case scenario because more patients were lost to follow-up than were accounted for, and in general, surgical results among missing patients are poorer than among those who return for follow-up. Variability in the addition of fibular periosteum augmentation and whether an orthopaedic surgeon or podiatrist performed the procedure did not account for these findings. With one third of patients reporting very-poor-to-fair results after these reconstructions, and many patients lost to follow-up, we recommend surgeons counsel their servicemember patients accordingly before surgery. Specifically, that there is a one third chance they will need permanent restrictions or have to leave the military postoperatively; analogously, we believe that our findings may apply to similarly active patients outside the military, and we question whether these procedures may not be serving such patients as well as previously believed.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: In-season return to play after anterior glenohumeral instability is associated with high rates of recurrent instability and the need for surgical stabilization. We are not aware of previous studies that have investigated in-season return to play after posterior glenohumeral instability; furthermore, as posterior shoulder instability in collision athletes occurs frequently, understanding the expected outcome of in-season athletes may improve the ability of physicians to provide athletes with a better understanding of the expected outcome of their injury and their ability to return to sport.Questions/purposes: (1) What proportion of athletes returned to play during the season after posterior instability in collegiate football players? (2) How much time did athletes lose to injury, what proportion of athletes opted to undergo surgery, and what proportion of athletes experienced recurrent instability after a posterior instability episode during a collegiate football season?Methods: A multicenter, prospective, observational study of National Collegiate Athletic Association (NCAA) Division 1 Football Bowl Subdivision athletes was performed at three US Military Service Academies. Ten athletes who sustained a posterior instability event during the regular football season and who pursued a course of nonoperative treatment were identified and prospectively observed through the subsequent season. All athletes in the observed cohort attempted an initial course of nonoperative treatment during the season. All athletes sustained subluxation events initially identified through history and physical examination at the time of injury. None of the athletes sustained a dislocation event requiring a manual reduction. Intraarticular pathology consisting of posterior labral pathology was further subsequently identified in all subjects via MRI arthrogram. Return to play was the primary outcome of interest. Time lost to injury, surgical intervention, and subsequent instability were secondary outcomes.Results: Of the 10 athletes who opted for a trial of initial nonoperative management, seven athletes were able to return to play during the same season. Although these seven athletes returned within 1 week of their injury (median of 1 day), 5 of 7 athletes sustained recurrent subluxation events with a median (range) of four subluxation events per athlete (0 to 8) during the remainder of the season. Seven athletes were treated surgically after the completion of their season, four of whom returned to football.Conclusion: This study suggests that although collegiate football players are able to return to in-season sport after a posterior glenohumeral instability event, they will likely sustain multiple recurrent instability events and undergo surgery after the season is completed. The results of this study can help guide in-season management of posterior shoulder instability by allowing more appropriate postinjury counseling and decision making through the identification of those athletes who may require additional attention from medical staff during the season and possible modifications to training regimens to minimize long-term disability. Further prospective studies involving a larger cohort over several seasons should be performed through collaborative studies across the NCAA that better assess function and injury risk factors before beginning collegiate athletics. This would better characterize the natural history and associated functional limitations that athletes may encounter during their collegiate careers.Level Of Evidence: Level IV, prognostic study. [ABSTRACT FROM AUTHOR]

Background: Rotator cuff arthropathy with loss of active arm elevation can be successfully treated with nonanatomic reverse total shoulder arthroplasty to restore active elevation. Shoulder kinematics in this context predominantly focus on glenohumeral motion, neglecting scapular motion, although both substantially contribute to global shoulder motion. Because scapular kinematics are difficult to assess clinically and in the laboratory, they are not well understood and therefore are often reduced to glenohumeral models with a static scapula.Questions/purposes: (1) Does the scapulohumeral rhythm (scapular rotation/glenohumeral elevation ratio) change during arm elevation? (2) Is there any scapular motion before arm elevation becomes clinically visible? (3) How do scapulothoracic kinematics during shoulder elevation differ between adults with and without rotator cuff arthropathy?Methods: This was a comparative kinematics study of 20 young adult volunteers (reference group) without rotator cuff impairment (seven females, 13 males; mean age: 27 ± 3.5 years) and 20 patients (22 shoulders) with cuff tear arthropathy (10 females, 10 males; mean age: 74 ± 6.2 years). We used a three-dimensional (3-D) motion analysis system from Vicom with eight high-speed infrared cameras (frame rate 200 Hz) and 25 skin markers. Kinematics were studied for scapulothoracic and glenohumeral movements using the Upper Limb Evaluation in Movement Analysis (ULEMA) open-source model. The main motion studied was active arm elevation in the scapular plane. After data cleaning, modeling, and normalization, changes of scapulohumeral rhythm and scapular motion at the beginning of arm elevation were analyzed qualitatively, and statistical parametric mapping was applied to study the difference in scapulothoracic kinematics between adults with and without rotator cuff arthropathy.Results: The scapular rhythm changes continuously during elevation. Whereas in people without rotator cuff arthropathy, a homogenous proportional relative angular contribution between 85° and 120° could be observed, this regular pattern was disturbed in patients with rotator cuff arthropathy. We observed medial scapular rotation before arm elevation became visible, followed by low lateral or even medial scapular rotation (approximately up to 25°) at the beginning of arm elevation. Patients with rotator cuff arthropathy exhibited more scapulothoracic motion between 50° and 93° of elevation than the reference group.Conclusions: Our study introduces a double-normalized data analysis that allows for a more detailed assessment of complex scapular kinematics in a noninvasive way. Scapulothoracic motion is more complex than previously reported, especially in patients with rotator cuff arthropathy. The scapulohumeral rhythm changes dynamically throughout arm elevation. There is counter-directed scapular rotation because of muscular engagement before clinically visible arm elevation. Compared with the homogenous shoulder kinematics in the reference group, patients with rotator cuff arthropathy show a different pattern with predominantly scapular motion in the range between 50° and 93° of arm elevation.Clinical Relevance: The findings of this study suggest that there is a specific pattern of scapular motion during arm elevation in patients with rotator cuff arthropathy. Our study introduces a new noninvasive method that allows for simultaneous analysis of glenohumeral and scapular kinematics. This will enable to investigators explore whether active arm elevation and the physiological motion pattern can be restored after, for example, reverse total shoulder arthroplasty despite a nonanatomic prosthesis configuration. [ABSTRACT FROM AUTHOR]

Background: Unexplained pain in the medial proximal tibia frequently leads to revision after unicondylar knee arthroplasty (UKA). As one of the most important factors for osteogenic adaptive response, increased bone strain following UKA has been suggested as a possible cause.Questions/purposes: In this study we: (1) performed a cadaver-based kinematic analysis on paired cadaveric specimens before and after mobile-bearing and fixed-bearing UKA; and (2) simultaneously characterized the strain distribution in the anterior and posterior proximal tibia during squatting.Methods: Five pairs of fresh, frozen full-leg cadaver specimens (four male, one female, 64 years to 87 years) were subjected to a dynamic squatting motion on a kinematic rig to simulate joint loading for a large ROM. Forces were applied to the quadriceps and hamstrings during the simulation while an infrared camera system tracked the location of reflective markers attached to the tibia and femur. Tibial cortical bone strain was measured with stacked strain gauge rosettes attached at predefined anterior and posterior positions on the medial cortex. Pairwise implantation of mobile-bearing (UKAMB) and fixed-bearing implants (UKAFB) allowed a direct comparison of right and left knees from the same donor through a linear mixed model.Results: UKAMB more closely replicated native kinematics in terms of tibial rotation and in AP and mediolateral translation. Maximum principal bone strain values were consistently increased compared with native (anteromedial, mean [± SD] peak strain: 311 µε ± 190 and posterior, mean peak strain: 321 µε ± 147) with both designs in the anteromedial (UKAFB, mean peak strain: 551 µε ± 381, Cohen's d effect size 1.3 and UKAMB, mean peak strain: 596 µε ± 564, Cohen's d effect size 1.5) and posterior (UKAFB, mean peak strain: 505 µε ± 511, Cohen's d effect size 1.3 and UKAMB, mean peak strain: 633 µε ± 424, Cohen's d effect size 2.1) region. However, in the anterolateral region of the medial tibial bone, UKAFB demonstrated the overall largest increase in strain (mean peak strain: 1010 µε ± 787, Cohen's d effect size 1.9), while UKAMB (613 µε ± 395, Cohen's d effect size 0.2) closely replicated values of the native knee (563 µε ± 234).Conclusion: In this in vitro cadaver study both UKAMB and UKAFB led to an increase in bone strain in comparison with the native knee. However, in the anterolateral region of the medial tibial plateau, proximal tibial bone strain was lower after UKAMB and UKAFB. Both UKAMB and UKAFB lead to comparable increases in anteromedial and posterior tibial strain in comparison with the native knee. In the anterolateral region of the medial tibial plateau UKA, proximal tibial bone strain was closer to the native knee after UKAMB than after UKAFB. In an attempt to link kinematics and strain behavior of these designs there seemed to be no obvious relation.Clinical Relevance: Further clinical research may be able to discern whether the observed differences in cortical strain after UKA is associated with unexplained pain in patients and whether the observed differences in cortical bone strain between mobile-bearing and fixed unicondylar designs results in a further difference in unexplained pain. [ABSTRACT FROM AUTHOR]

Background: Anchored transosseous equivalent suture-bridge technique (TOE) is widely used for arthroscopic rotator cuff repair. It is unknown how patient outcomes scores, ROM, and integrity of the rotator cuff after repair using this anchored technique compare with those after repair using an anchorless transosseous technique (TO).Questions/purposes: (1) What are the differences in patient-reported outcomes (American Shoulder and Elbow Surgeons [ASES] score) and shoulder ROM between TO and TOE rotator cuff repair techniques at 1 and 2 years after surgery? (2) What is the difference in repair integrity as measured by the re-tear rate, assessed ultrasonographically at 1 year, between these two techniques? (3) What is the difference in procedure duration between the two techniques when performed by a surgeon familiar with each?Methods: We reviewed 331 arthroscopic rotator cuff repairs performed by one surgeon from December 2011 to July 2016 in this retrospective, matched-pair study. Of these patients, 63% (208 of 331) underwent repair with standard anchored technique (anchors placed in a double-row, TOE manner) and 37% (123 of 331) underwent anchorless TO repair, with the same indications for surgery between groups. Forty-four percent (91 of 208) of patients in the TOE group and 61% (75 of 123) of patients in the TO group met the inclusion criteria. Eighty percent (73 of 91) of patients in the TOE group and 88% (66 of 75) in the TO group had minimum 2-year follow-up. We matched each group to a cohort of 50 patients by sex, age, smoking status, and tear size (by Cofield classification: small, < 1 cm; medium, 1-3 cm; large, > 3-5 cm; or massive, > 5 cm). The resulting cohorts did not differ in mean age (TO, 62 years [range 53-65 years]; TOE, 58 years [range 53-65 years]; p = 0.79), mean BMI value (TO, 30 [range 27-33]; TOE, 29 [range 27-35]; p = 0.97), or dominant arm involvement (TO, 80%; TOE, 78%; p = 0.81). The cohorts were followed for at least 2 years (median, 3.2 years [interquartile range (IQR) 2.2-4.3] for TO and 2.9 years [IQR 2.0-3.5 years] for TOE). ASES scores and ROM were evaluated before surgery and at follow-up visits and were recorded in a longitudinally maintained institutional database. Repair integrity was assessed using ultrasonography at 1 year, as is standard in our practice. For each tear-size group, we calculated the proportion of intact tendon repairs versus the proportion of re-tears. Duration of surgery was recorded for each patient.Results: At 1 year, we observed no difference in median ASES scores (90 [IQR 92-98] for TO and 88 [IQR 72-98] for TOE; p = 0.44); external rotation (50° [IQR 45°-60°) for TO and 50° [IQR: 40°-60°] for TOE; p = 0.58); forward flexion (165° [IQR 160°-170°] for both groups; p = 0.91); or abduction (100° [IQR 90°-100°] for TO and 90° [IQR 90°-100°] for TOE; p = 0.06). Fourteen percent of shoulders (seven of 50) in each treatment group had evidence of re-tear at 1 year (p > 0.99): 0 of 2 small tears in each group, 0 of 7 medium tears in each group, five of 32 large tears in each group, and two of 9 massive tears in each group (all, p > 0.99). At 2 years, we found no differences in median ASES scores (92 [IQR 74-98)] for TO and 90 [IQR 80-100] for TOE; p = 0.84); external rotation (60° [IQR 50°-60°] for both groups; p = 0.74); forward flexion (170° [IQR 160°-170°] for both groups; p = 0.69); or abduction (100° [IQR 90°-100°] for both groups; p = 0.95). We found no differences between groups in mean ± SD procedure time, which was 103 ± 20 minutes for TO repair and 99 ± 20 minutes for TOE repair (p = 0.45).Conclusions: TO and TOE techniques for arthroscopic rotator cuff repair results in no differences in ROM, ASES scores, re-tear rates, and surgical time. Randomized control trials are needed to confirm these similarities or determine a superior method of repair. Future cost analyses may also help to determine the relative value of each technique.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: The number of revisions after TKA is expected to rise because of aging populations in many countries and because patients are undergoing TKA at younger ages. Aseptic loosening is a major reason for late revision, which can be predicted by radiostereometric analysis (RSA) of small groups of patients at 2 years of follow-up. RSA is therefore an ideal tool to assess new TKA designs before they are introduced to the market, although not every TKA design has been studied with RSA. If RSA-tested TKA designs have lower 10-year revision rates in national registries than non-RSA-tested TKA designs, RSA testing of all new designs could be advocated.Questions/purposes: In this study, we asked: Is there a difference in the all-cause revision rate between non-RSA-tested and RSA-tested TKA designs registered in national knee arthroplasty registries at 5 and 10 years of follow-up?Methods: Knee arthroplasty registries were identified through the European Federation of National Associations of Orthopaedics and Traumatology webpage and through a manual internet search. Inclusion criteria were a minimum follow-up duration of 10 years and available revision or survival data per TKA design. Twenty-six registries were identified; seven were included comprising 339 TKA designs, of which 236 designs were classified as RSA-tested and 103 as non-RSA-tested. Six registries were excluded because no report was published. One registry was excluded because no fixation method was mentioned (79 TKA designs). Another registry was excluded because there was no 10-year data available (22 non-RSA-tested designs; 10 RSA-tested designs). Eleven registries were excluded because they did not provide revision rates per design and had not reached 10 years follow-up. The revision rates with their standard errors were extracted per design. We used the data from a recent meta-analysis to identify whether a TKA design was previously tested with RSA. This meta-analysis found 53 RSA studies comprising 70 different TKA designs. The prosthesis model, fixation method and insert type were extracted from these RSA-studies. The design characteristics of the TKA reported in the knee arthroplasty registries were also extracted, and if possible, matched to the TKA designs reported in the RSA-studies. At 5 years of follow-up, 191 TKA designs were identified as non-RSA-tested and 92 were identified as RSA-tested. At 10 years of follow-up, 154 TKA designs and 74 TKA designs were classified as non-RSA-tested and RSA-tested, respectively. A random-effects model using the Metafor Package in R statistics was used to estimate the pooled revision rate at 5 and 10 years of follow-up for both groups. The difference in revision rates between groups at 5 and 10 years of follow-up was estimated by including RSA as a factor in the random-effects model.Results: Mean all-cause revision rates at 5 years for non-RSA-tested and RSA-tested implants were 3.6% (95% CI 3.4 to 3.8) and 2.9% (95% CI 2.7 to 3.0), with a mean difference of 0.6% favoring RSA-tested implants (95% CI 0.4 to 0.8; p < 0.001). Mean all-cause revision rates at 10 years for non-RSA-tested and RSA-tested implants were 5.5% (95% CI 5.2 to 5.9) and 4.4% (95% CI 4.1 to 4.7), with a mean difference of 0.9% favoring RSA-tested implants (95% CI 0.4 to 1.3; p < 0.001).Conclusions: Although there are exceptions, across registries, TKA designs that have been tested in an RSA setting have a slightly lower (about 1%) mean all-cause revision rate at 5-year and 10-year follow-up than those tested in a non-RSA setting. Acknowledging the inherent limitations of this observational study, a risk difference of 1% could potentially translate into an approximate 20% decrease in revision burden up to 10 years, which may have a profound impact on patient morbidity and health-related costs.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: In kinematic alignment in TKA, the aim is to match the implant's position to the pre-arthritic anatomy of an individual patient, in contrast to the traditional goal of neutral mechanical alignment. However, there are limited mid-term, comparative data for survivorship and functional outcomes for these two techniques.Questions/purposes: In the setting of a randomized, controlled trial at 5 years, is there a difference between kinematic alignment and mechanical alignment in TKA in terms of (1) patient-reported outcome measures, (2) survivorship free from revision or reoperation, and (3) the incidence of radiographic aseptic loosening?Methods: In the initial study, 99 primary TKAs for osteoarthritis were randomized to either the mechanical alignment (n = 50) or kinematic alignment (n = 49) group. Computer navigation was used in the mechanical alignment group, and patient-specific cutting blocks were used in the kinematic alignment group. At 5 years, 95% (48 of 50) of mechanical alignment and 96% (47 of 49) of kinematic alignment TKAs were available for follow-up. Knee function was assessed using the Knee Society Score (KSS), VAS, Oxford Knee Score (OKS), WOMAC, Forgotten Joint Score (FJS) and EuroQol 5D. Survivorship free from reoperation (any reason) and revision (change or addition of any component) was determined via Kaplan-Meier analysis. Radiographs were assessed for signs of aseptic loosening (as defined by the presence of progressive radiolucent lines in two or more zones) by a single blinded observer.Results: At 5 years, there were no differences in any patient-reported outcome measure between the two groups. For example, the mean OKS did not differ between the two groups (kinematic alignment: 41.4 ± 7.2 versus mechanical alignment: 41.7 ± 6.3; difference -0.3 [95% confidence interval - 3.2 to 2.5]; p = 0.99). At 5 years, survivorship free from reoperation was 92.2 (95% CI 80.4 to 97.0) for mechanical alignment and 89.7 (95% CI 77.0 to 95.6) for kinematic alignment (log rank test; p = 0.674), survivorship free from revision was 94.1 (95% CI 82.9 to 98.1) for mechanical alignment and 95.9 (95% CI 84.5 to 99.0) for kinematic alignment (log rank test; p = 0.681). At 5 years, one patient demonstrated radiographic aseptic loosening for the mechanical alignment group; no cases were identified for the kinematic alignment group.Conclusions: We found no mid-term functional or radiographic differences between TKAs with mechanical alignment or kinematic alignment. The anticipated improvements in patient-reported outcomes with kinematic alignment were not realized. Because kinematic alignment results in a high proportion of patients whose tibial components are inserted in varus, loosening remains a potential long-term concern. Given the unknown impact on long-term survivorship of the substantial alignment alterations with kinematic alignment, our findings do not support the routine use of kinematic alignment outside of a research setting.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: TKA generally has excellent long-term survivorship. When a new knee system supersedes a previous model, increased survivorship, improved functional performance, or both may be expected, because key areas of design modification are often targeted to address wear, stability, and the patellofemoral articulation. However, not all design changes are beneficial, and to our knowledge, knee arthroplasty has not been systematically evaluated in the context of design changes that occur during the development of new knee arthroplasty systems.Questions/purposes: Using the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) we performed multiple old-to-new comparisons of frequently used contemporary knee implants to ask: (1) does overall prosthesis survivorship free from revision increase when a new knee prosthesis system is introduced to replace a prior prosthesis system? (2) Has survivorship free from revision improved for the revision indications of wear, instability, and patellofemoral articulation issues, where development efforts have been concentrated?Methods: Data from the AOANJRR from September 1999 to December 2017 were used to compare the survivorship of prostheses free from revision at a maximum of 17 years in procedures where a new design model was introduced to replace a prior knee system from the same manufacturer. Only prosthesis systems used in a minimum of 2000 primary TKA procedures for osteoarthritis that had a minimum of 5 years of follow-up were included. Varus-valgus constrained and hinge TKA designs were excluded. Cruciate-retaining, posterior-stabilized, and medial pivot-design knees were considered separately. The new and old prosthesis systems were paired for analysis. Survivorship was calculated with Kaplan Meier estimates and comparisons were performed using the Cox proportional hazards method. Subanalyses according to the three main revision indications were performed, and where possible, analyses were performed based on polyethylene types (highly cross-linked polyethylene and ultra-high-molecular-weight polyethylene), combined and separated. Revision was defined as a reoperation of a previous knee arthroplasty in which one or more of the components was removed, replaced, or added. There were 323,955 TKA procedures and 11 new prosthesis system designs that were introduced to replace an earlier knee system from the same manufacturer. Of these prosthesis system pairs, six were cruciate-retaining prostheses, four were posterior-stabilized designs, and one was a medial pivot design.Results: Six of the 11 knee system pairs showed improved survivorship with the new design, three were no different, and in two, the newer prosthesis systems had a higher rate of revision than the old one did. When revision for wear was analyzed, five prosthesis systems showed improvement, five were no different, and one had a higher rate of revision than the previous system did. There was no improvement in the rate of revision for instability; seven new prosthesis systems showed no difference from the previous system and four new prosthesis systems had a higher rate of revision than the previous system did. A subanalysis of revision for patellofemoral complications showed improvement in two comparisons, no difference in six, and a higher revision rate in two; one could not be calculated because of an insufficient number of revisions for this reason.Conclusions: It is difficult to predict whether a new system will demonstrate better survival than a previous one, and widespread uptake of a new design before a benefit is shown in robust clinical studies is unwise. Similarly, adoption of a new system for which there is no difference in survivorship from a previous model may be premature because a new device may have associated unknown and unintended consequences. Healthcare policy makers and therapeutic device regulators should similarly be guided by results and seek out peer-reviewed evidence before accepting change to established practice. Surgeons must be aware that implant changes may not translate into better survivorship and must seek compelling evidence of improvement in survival and/or function before changing systems.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Patellofemoral arthroplasty (PFA) is one option for the treatment of isolated patellofemoral osteoarthritis, but there are limited data regarding the procedure and results. Because isolated patellofemoral arthritis is relatively uncommon, available case series generally are small, and even within national registries, sample sizes are limited. Combining data from multiple registries may aid in assessing worldwide PFA usage and survivorship.Questions/purposes: We combined and compared data from multiple large arthroplasty registries worldwide to ask: (1) What proportion of patients undergoing primary knee arthroplasty have PFA? (2) What are the patient and prosthesis characteristics associated with PFA in common practice, as reflected in registries? (3) What is the survivorship free from revision of PFA and what are the reasons for and types of revisions?Methods: Data were provided by eight registries that are members of the International Society of Arthroplasty Registries (ISAR) who agreed to share aggregate data: Australia, New Zealand, Canada, Sweden, Finland, Norway, the Netherlands, and the United States. De-identified data were obtained for PFA performed from either the beginning of year 2000, or the earliest recorded implantation date after that in each individual registry when PFA data collection commenced, up to December 31, 2016. This included patient demographics, implant use, all-cause revision rate (determined by cumulative percent revision [CPR]), and reasons for and type of revision.Results: During the data collection period, 6784 PFAs were performed in the eight countries. PFAs comprised less than 1% of primary knee replacements in all registries. Patient demographics were comparable in all countries. Patients were generally more likely to be women than men, and the mean age ranged from 50 years to 60 years. All registries showed a high rate of revision for PFA. The 5-year CPR for any reason ranged from 8.0% (95% CI 4.5 to 11.5) in Norway to 18.1% (95% CI 15.5 to 20.7) in the Netherlands. The most common reason for revision across all countries was disease progression (42%, 434 of 1034). Most PFAs (83%, 810 of 980) were revised to a TKA.Conclusions: The revision risk of PFA in all registries surveyed was more than three times higher than the reported revision risk of TKA at the same times. The survivorship of PFA is similar to that of the no-longer-used procedure of metal-on-metal conventional hip replacement. Although there may be potential functional benefits from PFA, these findings of consistent and alarmingly high rates of revision should create concern, particularly as this procedure is often used in younger patients.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Robotic-assisted TKA was introduced to enhance the precision of bone preparation and component alignment with the goal of improving the clinical results and survivorship of TKA. Although numerous reports suggest that bone preparation and knee component alignment may be improved using robotic assistance, no long-term randomized trials of robotic-assisted TKA have shown whether this results in improved clinical function or survivorship of the TKA.Questions/purposes: In this randomized trial, we compared robotic-assisted TKA to manual-alignment techniques at long-term follow-up in terms of (1) functional results based on Knee Society, WOMAC, and UCLA Activity scores; (2) numerous radiographic parameters, including component and limb alignment; (3) Kaplan-Meier survivorship; and (4) complications specific to robotic-assistance, including pin-tract infection, peroneal nerve palsy, pin-site fracture, or patellar complications.Methods: This study was a registered prospective, randomized, controlled trial. From January 2002 to February 2008, one surgeon performed 975 robotic-assisted TKAs in 850 patients and 990 conventional TKAs in 849 patients. Among these patients 1406 patients were eligible for participation in this study based on prespecified inclusion criteria. Of those, 100% (1406) patients agreed to participate and were randomized, with 700 patients (750 knees) receiving robotic-assisted TKA and 706 patients (766 knees) receiving conventional TKA. Of those, 96% (674 patients) in the robotic-assisted TKA group and 95% (674 patients) in the conventional TKA group were available for follow-up at a mean of 13 (± 5) years. In both groups, no patient older than 65 years was randomized because we anticipated long-term follow-up. We evaluated 674 patients (724 knees) in each group for clinical and radiographic outcomes, and we examined Kaplan-Meier survivorship for the endpoint of aseptic loosening or revision. Clinical evaluation was performed using the original Knee Society knee score, the WOMAC score, and the UCLA activity score preoperatively and at latest follow-up visit. We also assessed loosening (defined as change in the position of the components) using plain radiographs, osteolysis using CT scans at the latest follow-up visit, and component, and limb alignment on mechanical axis radiographs. To minimize the chance of type-2 error and increase the power of our study, we assumed the difference in the Knee Society score to be 25 points to match the MCID of the Knee Society score with a SD of 5; to be able to detect a difference of this size, we calculated that a total of 628 patients would be needed in each group in order to achieve 80% power at the α = 0.05 level.Results: Clinical parameters at the latest follow-up including the Knee Society knee scores (93 ± 5 points in the robotic-assisted TKA group versus 92 ± 6 points in the conventional TKA group [95% confidence interval 90 to 98]; p = 0.321) and Knee Society knee function scores (83 ± 7 points in the robotic-assisted TKA group versus 85 ± 6 points in the conventional TKA group [95% CI 75 to 88]; p = 0.992), WOMAC scores (18 ± 14 points in the robotic-assisted TKA group versus 19 ± 15 points in the conventional TKA group [95% CI 16 to 22]; p = 0.981), range of knee motion (125 ± 6° in the robotic-assisted TKA group versus 128 ± 7° in the conventional TKA group [95% CI 121 to 135]; p = 0.321), and UCLA patient activity scores (7 points versus 7 points in each group [95% CI 5 to 10]; p = 1.000) were not different between the two groups at a mean of 13 years' follow-up. Radiographic parameters such as the femorotibial angle (mean 2° ± 2° valgus in the robotic-assisted TKA group versus 3° ± 3° valgus in the conventional TKA group [95% CI 1 to 5]; p = 0.897), femoral component position (coronal plane: mean 98° in the robotic-assisted TKA group versus 97° in the conventional TKA group [95% CI 96 to 99]; p = 0.953; sagittal plane: mean 3° in the robotic-assisted TKA group versus 2° in the conventional TKA group [95% CI 1 to 4]; p = 0.612) and tibial component position (coronal plane: mean 90° in the robotic-assisted TKA group versus 89° in the conventional TKA group [95% CI 87 to 92]; p = 0.721; sagittal plane: 87° in the robotic-assisted TKA group versus 86° in the conventional TKA group [95% CI 84 to 89]; p = 0.792), joint line (16 mm in the robotic-assisted TKA group versus 16 mm in the conventional TKA group [95% CI 14 to 18]; p = 0.512), and posterior femoral condylar offset (24 mm in the robotic-assisted TKA group versus 24 mm in the conventional TKA group [95% CI 21 to 27 ]; p = 0.817) also were not different between the two groups (p > 0.05). The aseptic loosening rate was 2% in each group, and this was not different between the two groups. With the endpoint of revision or aseptic loosening of the components, Kaplan-Meier survivorship of the TKA components was 98% in both groups (95% CI 94 to 100) at 15 years (p = 0.972). There were no between-group differences in terms of the frequency with which complications occurred. In all, 0.6% of knees (four) in each group had a superficial infection, and they were treated with intravenous antibiotics for 2 weeks [corrected]. No deep infection occurred in these knees. In the conventional TKA group, 0.6% of knees (four) had motion limitation (< 60°) [corrected].Conclusions: At a minimum follow-up of 10 years, we found no differences between robotic-assisted TKA and conventional TKA in terms of functional outcome scores, aseptic loosening, overall survivorship, and complications. Considering the additional time and expense associated with robotic-assisted TKA, we cannot recommend its widespread use.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Correct quantification of femoral torsion is crucial to diagnose torsional deformities, make an indication for surgical treatment, or plan the amount of correction. However, no clear evaluation of different femoral torsion measurement methods for hips with excessive torsion has been performed to date.Questions/purposes: (1) How does CT-based measurement of femoral torsion differ among five commonly used measurement methods? (2) Do differences in femoral torsion among measurement methods increase in hips with excessive femoral torsion? (3) What is the reliability and reproducibility of each of the five torsion measurement methods?Methods: Between March and August 2016, we saw 86 new patients (95 hips) with hip pain and physical findings suggestive for femoroacetabular impingement at our outpatient tertiary clinic. Of those, 56 patients (62 hips) had a pelvic CT scan including the distal femur for measurement of femoral torsion. We excluded seven patients (seven hips) with previous hip surgery, two patients (two hips) with sequelae of Legg-Calvé-Perthes disease, and one patient (one hip) with a posttraumatic deformity. This resulted in 46 patients (52 hips) in the final study group with a mean age of 28 ± 9 years (range, 17-51 years) and 27 female patients (59%). Torsion was compared among five commonly used assessment measures, those of Lee et al., Reikerås et al., Jarrett et al., Tomczak et al., and Murphy et al. They differed regarding the level of the anatomic landmark for the proximal femoral neck axis; the method of Lee had the most proximal definition followed by the methods of Reikerås, Jarrett, and Tomczak at the base of the femoral neck and the method of Murphy with the most distal definition at the level of the lesser trochanter. The definition of the femoral head center and of the distal reference was consistent for all five measurement methods. We used the method described by Murphy et al. as our baseline measurement method for femoral torsion because it reportedly most closely reflects true anatomic femoral torsion. With this method we found a mean femoral torsion of 28 ± 13°. Mean values of femoral torsion were compared among the five methods using multivariate analysis of variance. All differences between two of the measurement methods were plotted over the entire range of femoral torsion to evaluate a possible increase in hips with excessive femoral torsion. All measurements were performed by two blinded orthopaedic residents (FS, TDL) at two different occasions to measure intraobserver reproducibility and interobserver reliability using intraclass correlation coefficients (ICCs).Results: We found increasing values for femoral torsion using measurement methods with a more distal definition of the proximal femoral neck axis: Lee et al. (most proximal definition: 11° ± 11°), Reikerås et al. (15° ± 11°), Jarrett et al. (19° ± 11°), Tomczak et al. (25° ± 12°), and Murphy et al. (most distal definition: 28° ± 13°). The most pronounced difference was found for the comparison between the methods of Lee et al. and Murphy et al. with a mean difference of 17° ± 5° (95% confidence interval, 16°-19°; p < 0.001). For six of 10 possible pairwise comparisons, the difference between two methods increased with increasing femoral torsion and decreased with decreasing femoral torsion. We observed a fair-to-strong linear correlation (R range, 0.306-0.622; all p values < 0.05) for any method compared with the Murphy method and for the Reikerås and Jarrett methods when compared with the Tomczak method. For example, a hip with 10° of femoral antetorsion according Murphy had a torsion of 1° according to Reikerås, which corresponds to a difference of 9°. This difference increased to 20° in hips with excessive torsion; for example, a hip with 60° of torsion according to Murphy had 40° of torsion according to Reikerås. All five methods for measuring femoral torsion showed excellent agreement for both intraobserver reproducibility (ICC, 0.905-0.973) and interobserver reliability (ICC, 0.938-0.969).Conclusions: Because the quantification of femoral torsion in hips with excessive femoral torsion differs considerably among measurement methods, it is crucial to state the applied methods when reporting femoral torsion and to be consistent regarding the used measurement method. These differences have to be considered for surgical decision-making and planning the degree of correction. Neglecting the differences among measurement methods to quantify femoral torsion can potentially lead to misdiagnosis and surgical planning errors.Level Of Evidence: Level IV, diagnostic study. [ABSTRACT FROM AUTHOR]

Background: The direct lateral approach to THA provides good exposure and is associated with a low risk of dislocations, but can result in damage to the abductor muscles. The direct anterior approach does not incise muscle, and so recovery after surgery may be faster, but it has been associated with complications (including fractures and nerve injuries), and it involves a learning curve for surgeons who are unfamiliar with it. Few randomized trials have compared these approaches with respect to objective endpoints as well as validated outcome scores.Questions/purposes: The purpose of this study was to compare the direct anterior approach with the direct lateral approach to THA with respect to (1) patient-reported and validated outcomes scores; (2) frequency and persistence of abductor weakness, as demonstrated by the Trendelenburg test; and (3) major complications such as infection, dislocation, reoperation, or neurovascular injury.Methods: We performed a randomized controlled trial recruiting patients from January 2012 to June 2013. One hundred sixty-four patients with end-stage osteoarthritis were included and randomized to either the direct anterior or direct lateral approach. Before surgery and at 3, 6, 12, and 24 months, a physiotherapist recorded the Harris hip score (HHS), 6-minute walk distance (6MWD), and performed the Trendelenburg test directly after the 6MWD. The patients completed the Oxford Hip Score (OHS) and the EQ-5D. The groups were not different at baseline with respect to demographic data and preoperative scores. Both groups received the same pre- and postoperative regimes. Assessors were blinded to the approach used. One hundred fifty-four patients (94%) completed the 2-year followup; five patients from each group were lost to followup.Results: There were few statistical differences and no clinically important differences in terms of validated or patient-reported outcomes scores (including the HHS, 6MWD, OHS, or EQ-5D) between the direct anterior and the lateral approach at any time point. A higher proportion of patients had a persistently positive Trendelenburg test 24 months after surgery in the lateral approach than the direct anterior approach (16% [12 of 75] versus 1% [one of 79]; odds ratio, 15; p = 0.001). Irrespective of approach, those with a positive Trendelenburg test had statistically and clinically important worse HHS, OHS, and EQ-5D scores than those with a negative Trendelenburg test. There were four major nerve injuries in the direct anterior group (three transient femoral nerve injuries, resolved by 3 months after surgery, and one tibial nerve injury with symptoms that persist 24 months after surgery) and none in the lateral approach.Conclusions: Based on our findings, no case for superiority of one approach over the other can be made, except for the reduction in postoperative Trendelenburg test-positive patients using the direct anterior approach compared with when using the direct lateral approach. Irrespective of approach, patients with a positive Trendelenburg test had clinically worse scores than those with a negative test, indicating the importance of ensuring good abductor function when performing THA. The direct anterior approach was associated with nerve injuries that were not seen in the group treated with the lateral approach.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Compression bandages often are used after TKA to reduce swelling. However, the degree to which they are helpful has not been well characterized.Questions/purposes: The purpose of this study was to determine whether use of a compression bandage after TKA was associated with (1) less leg swelling (our primary endpoint); or (2) secondary study endpoints, including improved ROM of flexion and extension, lower visual analog scale (VAS) pain scores for worst pain and pain during physical therapy just before surgery, postoperative day (POD) 1, POD 2, and POD 28, or fewer wound complications within 90 days of surgery.Methods: A prospective, single-center, two-arm, parallel-group randomized controlled trial was conducted on 51 patients undergoing simultaneous, bilateral, primary TKA between February 2015 and August 2016. Patients were excluded if they had a body mass index > 40 kg/m, a history of a venous thromboembolic event, an allergy to the dressing or compression bandage, or lymphedema in one or both legs. Participants averaged a mean age of 62 years (range, 40-83 years). In all patients, we released the tourniquet after full wound closure, and we applied an Aquacel dressing to both limbs. Patients were randomized by opaque envelope, and the compression bandage was applied to the randomized limb. For each leg, study personnel not involved in patient care measured the patients' limb circumference (thigh, knee, and tibia), ROM, and VAS pain scores 24 hours after surgery, 48 hours after surgery, and on POD 28. The minimal clinically important difference for circumference was 2 cm with a SD of 2 cm in the circumference. For VAS, it was 2 points with a SD of 2. For ROM, it was 10° with a SD of 15. We conservatively picked an effect size of 0.5 SD and assumed a correlation between limbs of 0.3. This set the power level at 0.80 with an α error of 0.05; thus, a power analysis for paired t-tests indicated that 45 patients would be an appropriate sample size. There were 29 patients randomized to the right leg group and 22 patients randomized to the left leg group. There were no differences between the limb with and without the compression bandage preoperatively.Results: Postoperatively, there were no differences between the groups in terms of leg swelling at the thigh (POD 1: mean ± SD = 51 ± 6 with compression bandage versus mean ± SD = 51 ± 6 without compression bandage, mean Δ = - 0.14, 95% confidence interval [CI], -0.65 to 0.37], p = 0.586; POD 2: mean ± SD = 53 ± 6 with compression bandage versus mean ± SD = 53 ± 7 without compression bandage, mean Δ = -0.22, 95% CI, -0.95 to 0.51, p = 0.548; POD 28: mean ± SD = 47 ± 6 with compression bandage versus mean ± SD = 47 ± 6 without compression bandage, mean Δ = -0.01, 95% CI, -0.39 to 0.38, p = 0.975), knee (POD 1: mean ± SD = 45 ± 4 with compression bandage versus mean ± SD = 45 ± 5 without compression bandage, mean Δ = -0.44, 95% CI, -1.16 to 0.28, p = 0.223; POD 2: mean ± SD = 46 ± 4 with compression bandage versus mean ± SD = 46 ± 4 without compression bandage, mean Δ = -0.30, 95% CI, -0.69 to 0.10, p = 0.137; POD 28: mean ± SD = 42 ± 5 with compression bandage versus mean ± SD = 42 ± 5 without compression bandage, mean Δ = 0.21, 95% CI, -0.34 to 0.76, p = 0.446), and shin (POD 1: mean ± SD = 40 ± 4 with compression bandage versus mean ± SD = 40 ± 4 without compression bandage, mean Δ = -0.22, 95% CI, -1.23 to 0.79, p = 0.659; POD 2: mean ± SD = 41 ± 4 with compression bandage versus mean ± SD = 41 ± 4 without compression bandage, mean Δ = -0.31, 95% CI, -0.72 to 0.09, p = 0.126; POD 28: mean ± SD = 37 ± 4 with compression bandage versus mean ± SD = 37 ± 4 without compression bandage, mean Δ = -0.34, 95% CI, -0.92 to 0.24, p = 0.246). There were no differences between the groups in terms of flexion ROM (POD 1: mean ± SD = 56 ± 25 with compression bandage versus mean ± SD = 58 ± 22 without compression bandage, mean Δ = -2.63, p = 0.234; POD 2: mean ± SD = 64 ± 20 with compression bandage versus mean ± SD = 63 ± 23 without compression bandage, mean Δ = 1.22, p = 0.534; POD 28: mean ± SD = 101 ± 20 with compression bandage versus mean ± SD = 102 ± 20 without compression bandage, mean Δ = -1.64, p = 0.103) and extension (POD 1: mean ± SD = 12 ± 7 with compression bandage versus mean ± SD = 12 ± 7 without compression bandage, mean Δ = 0.51, p = 0.328; POD 2: mean ± SD = 9 ± 5 with compression bandage versus mean ± SD = 10 ± 6 without compression bandage, mean Δ = -1.28, p = 0.061; POD 28: mean ± SD = 6 ± 14 with compression bandage versus mean ± SD = 4 ± 4 without compression bandage, mean Δ = 2.19, p = 0.252). With the numbers available, we observed greater maximal postoperative pain for the limb with the compression bandage than the control limb on POD 1 and POD 2, but not on POD 28 (POD 1: mean ± SD = 8 ± 3 with compression bandage versus mean ± SD = 7 ± 3 without compression bandage, mean Δ = 0.66, p = 0.030; POD 2: mean ± SD = 7 ± 2 with compression bandage versus mean ± SD = 7 ± 3 without compression bandage, mean Δ = 0.80, p = 0.008; POD 28: mean ± SD = 4 ± 3 with compression bandage versus mean ± SD = 3 ± 3 without compression bandage, mean Δ = 0.14, p = 0.526). Likewise, there was greater pain during physical therapy for the limb with the compression bandage than the limb without on POD 2, but not on POD 1 and POD 28 (POD 1: mean ± SD = 7 ± 3 with compression bandage versus mean ± SD = 6 ± 3 without compression bandage, mean Δ = 0.29, p = 0.460; POD 2: mean ± SD = 8 ± 2 with compression bandage versus mean ± SD = 7 ± 3 without compression bandage, mean Δ = 0.67, p = 0.018; POD 28: mean ± SD = 5 ± 2 with compression bandage versus mean ± SD = 5 ± 3 without compression bandage, mean Δ = 0.14, p = 0.600). With the numbers available, we observed no difference in 90-day wound healing complications between the limb with and the limb without the compression dressing; however, the sample size was too small to analyze this in a meaningful statistical way. Overall, there were 6% total wound complications in the compression bandage group and 12% total wound complications in the group without the compression bandage (odds ratio [OR], 0.47; p = 0.487). Drainage was not observed in the group with the compression bandage, whereas the group without the compression bandage had 6% drainage (OR, 0.00; p = 0.243). There were no deep infections or reoperations within 90 days postoperatively.Conclusions: Applying a compression bandage after TKA did not result in any clinical improvement in limb circumference, ROM, or pain. Based on this study, we believe that applying a compression bandage after TKA neither benefits nor harms the patient. Thus, we no longer use compression dressings for routine primary TKA.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Concerns about the cost and convenience of postsurgical physical therapy (PT) have sparked interest in unsupervised, home-based rehabilitation. However, the effectiveness of unsupervised home exercise after primary TKA has not been previously evaluated.Questions/purposes: (1) Can unsupervised home exercise after surgery provide noninferior recovery of passive knee flexion compared with formal outpatient PT? (2) Does a web-based platform for home-based exercise provide an advantage compared with a printed PT manual?Methods: We conducted a randomized, noninferiority trial involving 290 patients (20% of the 1464 eligible patients who could be contacted) who underwent primary TKA from March 2016 to April 2018. We included patients > 18 years old who were undergoing primary, unilateral TKA and provided written consent. We excluded patients with preoperative knee flexion < 90°, patients considering surgical intervention in a hip or the contralateral knee, patients discharged to an extended care facility, and revision or conversion TKA. We randomized patients to one of three groups: outpatient PT, unsupervised home exercise using a web-based platform (web PT), or unsupervised home exercise using a printed paper manual (paper PT). We also implemented a "delayed recovery intervention" within the home exercise program, in which patients were obliged to begin outpatient PT if knee flexion was < 70° at 2 weeks or < 90° at 4 weeks. The primary outcome was change in knee flexion from preoperative baseline after 4 to 6 weeks and 6 months. Secondary outcomes included Knee Injury and Osteoarthritis Outcome Score (KOOS), time back to activities of daily living, and time off narcotics. All analyses were intention to treat, and the noninferiority margin was 5% with maximum flexion as the outcome of interest for this parameter.Results: Adjusted differences in change in passive flexion for web PT +3° (95% confidence interval [CI], -1.2° to 6.4°) and paper PT +5° (95% CI, 0.99°-8.6°) were not inferior to outpatient PT based on a predefined 5° margin. Change in knee flexion from baseline was 0° for outpatient PT, -2° for web PT, and -1° for paper PT after 4 to 6 weeks and 8°, 8°, and 12° for the three groups, respectively, after 6 months. Additionally, there was no difference in the change in KOOS from baseline at 4 to 6 weeks or 6 months postoperatively as well as time back to work, driving, and walking without an assistive device.Conclusions: Unsupervised home exercise is an effective rehabilitation strategy after primary TKA and was noninferior to formal outpatient PT in selected patients. It is worthwhile to reconsider the current practice of automatically designating patients for outpatient PT after primary TKA, because appropriately selected patients with adequate clinical support can achieve similar results at home.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Methods to reduce the revision rate of total knee prostheses because of wear-related issues are important to examine, particularly because younger patients have a disproportionately high risk of revision.Questions/purposes: (1) Are long-term Knee Society knee and function scores better in younger patients with an oxidized zirconium (OxZr) TKA compared with those with a cobalt-chrome (CoCr) TKA? (2) Are there differences in radiographic signs of loosening or CT findings of osteolysis between OxZr TKAs and CoCr TKAs? (3) Are there fewer polyethylene wear particles in the OxZr TKA than CoCr TKA? (4) Do the groups differ in terms of survivorship free from revision surgery at 13 years?Methods: From April 2003 to January 2007, we enrolled 110 patients younger than 55 years of age in this randomized, double-blind, prospective trial. Each patient served as his or her own control and each received an OxZr femoral component in one knee and a CoCr femoral component in the other. The minimum followup was 10 years (mean, 13 years; range, 10-14 years); two died and nine were lost to followup before that time, leaving 99 patients (198 knees) for analysis. There were 28 men and 71 women with a mean age of 53 ± 6 years (range, 40-55 years). We obtained Knee Society knee scores for each knee, but Knee Society function scores, WOMAC scores, and UCLA activity scores were obtained for each patient preoperatively and at each followup. Additionally, we performed radiographic examination preoperatively and at each followup. At a minimum of 10 years (mean, 13 years) followup, we obtained CT scans in all patients. Polyethylene wear particles in the synovial fluid were analyzed at the final followup using thermogravimetric methods and scanning electron microscopy. Survivorship was ascertained using the Kaplan-Meier calculator. A sample size calculation determined that to detect a difference in the Knee Society knee score of 5 points, assuming a SD of 5 points, with an α = 0.05 and β = 0.80, a total of 90 patients would be needed in each group.Results: At the most recent followup, the mean Knee Society knee scores (92 versus 93 points; p = 0.857), function scores (85 versus 85 points; p = 1.000), WOMAC scores (23 versus 23 points; p = 1.000), UCLA activity scores (6.5 versus 6.5 points; p = 1.000), and range of knee motion (125° versus 127°; p = 0.365) were not different between the two groups. There was no radiographic evidence of loosening and no osteolysis visible on CT scan in either group. The weight of polyethylene wear particles produced at the bearing surface was 0.046 ± 0.010 g in 1 g of synovial fluid in patients with an OxZr femoral component and 0.0448 ± 0.0108 g in patients with a CoCr femoral component (p = 0.583). Kaplan-Meier survivorship free from revision was 97% for the OxZr group (95% confidence interval [CI], 93-100) and 98% for the CoCr group (95% CI, 93-100) at 13 years after surgery (p = 0.918).Conclusions: Given the absence of demonstrated superiority of either the CoCr implant or the OxZr implant, we recommend that surgeons and healthcare systems can reasonably choose the less expensive device for routine use, unless there is some compelling reason in an individual patient to choose one over the other (such as severe, documented metal sensitivity).Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Restoring normal femoral rotation is an important consideration when managing femur fractures. Femoral malrotation after fixation is common and several preventive techniques have been described. Use of the lesser trochanter profile is a simple method to prevent malrotation, because the profile changes with femoral rotation, but the accuracy of this method is unclear.Questions/purposes: The purposes of this study were (1) to report the rotational profiles of uninjured femora in an adult population; and (2) to determine if the lesser trochanter profile was associated with variability in femoral rotation.Methods: One hundred fifty-five consecutive patients (72% female and 28% male) with a mean age of 32 years (range, 12-56 years) with a CT scanogram were retrospectively evaluated. Patients were included if CT scanograms had adequate cuts of the proximal and distal femur. Patients were excluded if they had prior hip/femur surgery or anatomic abnormalities of the proximal femur. CT scanogram measurements of femoral rotation were compared with the lesser trochanter profile (distance from the tip of the lesser trochanter to the medial cortex of the femur) measured on weightbearing AP radiographs. These measurements were made by a single fellowship-trained orthopaedic surgeon and repeated for intraobserver reliability testing. Presence of rotational differences based on sex and laterality was assessed and correlation of the difference in lesser trochanter profile to the difference in femoral rotation was determined using a coefficient of determination (r).Results: The mean femoral rotation was 10.9° (SD ± 8.8°) of anteversion. Mean right femoral rotation was 11.0° (SD ± 8.9°) and mean left femoral rotation was 10.7° (SD ± 8.7°) with a mean difference of 0.3° (95% confidence interval [CI], -1.7° to 2.3°; p = 0.76). Males had a mean rotation of 9.4°(SD ± 7.7°) and females had a mean rotation of 11.5° (SD ± 9.1°) with a mean difference of 2.1° (95% CI, -0.1° to 4.3°; p = 0.06). Mean lesser trochanter profile was 6.6 mm (SD ± 4.0 mm). Mean right lesser trochanter profile was 6.6 mm (SD ± 3.9 mm) and mean left lesser trochanter profile was 6.5 mm (SD ± 4.0 mm) with a mean difference of 0.1 mm (-0.8 mm to 1.0 mm, p = 0.86). The lesser trochanter profile varied between the sexes; males had a mean of 8.3 mm (SD ± 3.4), and females had a mean of 5.9 mm (SD ± 4.0). The mean difference between sexes was 2.5 mm (1.5-3.4 mm; p < 0.001). The magnitude of the lesser trochanter profile measurement and degree of femoral rotation were positively correlated such that increasing measures of the lesser trochanter profile were associated with increasing amounts of femoral anteversion. The lesser trochanter profile was associated with femoral version in a linear regression model (r = 0.64; p < 0.001). Thus, 64% of the difference in femoral rotation can be explained by the difference in the lesser trochanter profile. Intraobserver reliability for both the femoral version and lesser trochanter profile was noted to be excellent with intraclass correlation coefficients of 0.94 and 0.95, respectively.Conclusions: This study helps define the normal femoral rotation profile among adults without femoral injury or bone deformity and demonstrated no rotational differences between sexes. The lesser trochanter profile was found to be positively associated with femoral rotation. Increasing and decreasing lesser trochanter profile measurements are associated with increasing and decreasing amounts of femoral rotation, respectively.Clinical Relevance: The lesser trochanter profile can determine the position of the femur in both anteversion and retroversion, supporting its use as a method to restore preinjury femoral rotation after fracture fixation. Although some variability in the rotation between sides may exist, matching the lesser trochanter profile between injured and uninjured femora can help reestablish native rotation. [ABSTRACT FROM AUTHOR]

Background: Some surgeons contend that unicompartmental knee arthroplasty (UKA) can easily be revised to a TKA when revision is called for, whereas others believe that this can be complex and technically demanding. There has been little research regarding the efficacy or rationale of using metal augmentation and tibial stem extensions when revising a UKA to a TKA. QUESTION/PURPOSES: (1) Is the use of stem extensions for the tibial component associated with increased survival when revising a UKA to a TKA? (2) Is the addition of modular augments associated with increased survival compared with stem extensions alone? (3) Is TKA design (minimally stabilized versus posterior-stabilized) or (4) tibial fixation (cemented versus cementless) associated with differences in survivorship?Methods: Data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) were used to analyze implant survival after revision of a UKA to a TKA, comparing results in which tibial components were used with and without modular components. The groups analyzed were TKA without a stem extension, those in which a tibial stem extension was used, and those in which a tibial stem extension was used together with an augment. There were 4438 revisions of UKAs to TKAs available for analysis. The mean duration of followup of patients having the TKA revisions was 5 years (SD, 3.5 years). There were 2901 (65%) procedures in which a tibial stem extension was not used, 870 (20%) procedures with a tibial stem extension, and 667 (15%) with a tibial stem extension and metallic augment. Kaplan-Meier estimates of survivorship were calculated and hazard ratios (HRs) from Cox proportional hazard models, adjusting for age and sex, were used to compare the rate of revision among groups. The overall 10-year cumulative percent revision (CPR) for UKA revised to a TKA was 16%.Results: At 10 years, the CPR was increased when a stem extension was not used (19%; 95% confidence interval [CI],16.5-20.7 without a stem extension compared with 13%; 95% CI, 9.2-17.0 with a stem extension; entire period HR, 1.44; 95% CI, 1.10-1.89; p = 0.007). There was no difference in the 10-year CPR when an augment was used together with a stem extension compared with a stem extension alone (HR, 1.26; 95% CI, 0.85-1.86; p = 0.251). When minimally stabilized and posterior-stabilized TKAs were compared, there was no difference in survivorship. Minimally stabilized TKA designs without stem extensions showed higher CPR compared with when stem extensions were used (HR, 1.77; 95% CI, 1.16-2.70; p = 0.007), whereas posterior-stabilized designs without stem extensions showed higher CPR only when compared with when stem extensions and augments were both used (HR, 2.16; 95% CI, 1.24-3.77; p = 0.006). Cementless fixation of the tibial component resulted in a higher CPR than when cement was used (HR, 1.36; 95% CI 1.08-1.71; p = 0.008).Conclusions: In this registry study, the risk of repeat revision after revision of a UKA to a TKA was lower when a tibial stem extension was used, but no such difference was found with respect to augments. Our study did not account for the degree of bone loss or surgeon preference when considering stems and augments. Further research to establish the degree of bone loss associated with UKA to TKA revision procedures will help clarify these findings.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Cup malposition is a common cause of impingement, limitation of ROM, acceleration of bearing wear, liner fracture, and instability in THA. Previous studies of the safe zone based on plain radiographs have limitations inherent to measuring angles from two-dimensional projections. The current study uses CT to measure component position in stable and unstable hips to assess the presence of a safe zone for cup position in THA.Questions/purposes: (1) Does acetabular component orientation, when measured on CT, differ in stable components and those revised for recurrent instability? (2) Do CT data support historic safe zone definitions for component orientation in THA?Methods: We identified 34 hips that had undergone revision of the acetabulum for recurrent instability that also had a CT scan of the pelvis between August 2003 and February 2017. We also identified 175 patients with stable hip replacements who also had a CT study for preoperative planning and intraoperative navigation of the contralateral side. For each CT study, one observer analyzed major factors including acetabular orientation, femoral anteversion, combined anteversion (the sum of femoral and anatomic anteversion), pelvic tilt, total offset difference, head diameter, age, sex, and body mass index. These measures were then compared among stable hips, hips with cup revision for anterior instability, and hips with cup revision for posterior instability. We used a clinically relevant measurement of operative anteversion and inclination as opposed to the historic use of radiographic anteversion and inclination. The percentage of unstable hips in the historic Lewinnek safe zone was calculated, and a new safe zone was proposed based on an area with no unstable hips.Results: Anteriorly unstable hips compared with stable hips had higher operative anteversion of the cup (44° ± 12° versus 31° ± 11°, respectively; mean difference, 13°; 95% confidence interval [CI], 5°-21°; p = 0.003), tilt-adjusted operative anteversion of the cup (40° ± 6° versus 26° ± 10°, respectively; mean difference, 14°; 95% CI, 10°-18°; p < 0.001), and combined tilt-adjusted anteversion of the cup (64° ± 10° versus 54° ± 19°, respectively; mean difference, 10°; 95% CI, 1°-19°; p = 0.028). Posteriorly unstable hips compared with stable hips had lower operative anteversion of the cup (19° ± 15° versus 31° ± 11°, respectively; mean difference, -12°; 95% CI, -5° to -18°; p = 0.001), tilt-adjusted operative anteversion of the cup (19° ± 13° versus 26° ± 10°, respectively; mean difference, -8°; 95% CI, -14° to -2°; p = 0.014), pelvic tilt (0° ± 6° versus 4° ± 6°, respectively; mean difference, -4°; 95% CI, -7° to -1°; p = 0.007), and anatomic cup anteversion (25° ± 18° versus 34° ± 12°, respectively; mean difference, -9°; 95% CI, -1° to -17°; p = 0.033). Thirty-two percent of the unstable hips were located in the Lewinnek safe zone (11 of 34; 10 posterior dislocations, one anterior dislocation). In addition, a safe zone with no unstable hips was identified within 43° ± 12° of operative inclination and 31° ± 8° of tilt-adjusted operative anteversion.Conclusions: The current study supports the notion of a safe zone for acetabular component orientation based on CT. However, the results demonstrate that the historic Lewinnek safe zone is not a reliable predictor of future stability. Analysis of tilt-adjusted operative anteversion and operative inclination demonstrates a new safe zone where no hips were revised for recurrent instability that is narrower for tilt-adjusted operative anteversion than for operative inclination. Tilt-adjusted operative anteversion is significantly different between stable and unstable hips, and surgeons should therefore prioritize assessment of preoperative pelvic tilt and accurate placement in operative anteversion. With improvements in patient-specific cup orientation goals and acetabular component placement, further refinement of a safe zone with CT data may reduce the incidence of cup malposition and its associated complications.Level Of Evidence: Level III, diagnostic study. [ABSTRACT FROM AUTHOR]

Background: Bone loss in patients undergoing revision THA poses a considerable challenge for orthopaedic surgeons. Often, to achieve better fixation in remaining bone, larger diameter acetabular components and reaming superiorly may be necessary. However, this is likely to raise the hip center of rotation, which may lead to altered biomechanics, specifically, insufficiency of the abductor muscles, altered gait, and increased risk of dislocation from impingement. More recently, a newer acetabular shell has been designed to more closely replicate the native hip center of rotation in these circumstances while maintaining adequate fixation.Questions/purposes: The purpose of this study was to compare the radiographic parameters of this newer design with conventional hemispheric cups in revision THA. Specifically, we assessed the differences in (1) vertical center of rotation (COR) displacement and (2) horizontal COR displacement.Methods: Between January 2016 and April 2016, five reconstructive surgeons at five institutions utilized a newer highly porous acetabular shell designed with peripheral screw holes and vertically eccentric COR to allow for restoration of center of hip rotation in revision THA. We included all patients who received this device. During this time, the general indications at these sites for using the new device included Paprosky Stage IIA, IIB, IIC, or IIIA acetabular defects. This yielded 29 patients who were subsequently matched (one to two) by cup size and sex to a cohort who underwent revision THA with conventional hemispheric cups between January 2015 and May 2016. To determine hip COR, radiographic measurements were performed. A circle contiguous to the acetabulum was drawn and the center was determined as the hip COR. All measurements were made from the interteardrop line for both the revised and native hips. A line through the teardrops was used for all horizontal measurements. Center position adjustments were made based on the manufacturer-specified values. Comparisons were performed using chi-square tests for categorical and t-tests for continuous variables. There was no difference in the severity of bone loss before the revision in the groups, as evidenced by Paprosky staging of preoperative radiographs.Results: The mean vertical COR displacement was smaller in patients who had the novel cup (3.5 mm; range, -12 to 15 mm; mean difference, -7.3 mm; 95% confidence interval [CI], -13.2 to -1.5) as compared with those who had the conventional cup (10.5 mm; range, -4 to 50 mm; mean difference, 7.3 mm; 95% CI, -12.5 to -2.2; p = 0.003). There was no difference in mean horizontal displacement between the two groups (-0.06 ± 6.1 versus 1.7 ± 7.1; mean difference, -1.8; p = 0.903).Conclusions: Although hip COR was improved based on radiographic measurements with the use of this novel acetabular design, and although this may improve hip biomechanics, more studies are required before its widespread adoption for revision cases of this nature can be recommended. Both implant costs and the risks associated with using a new design in practice will have to be justified by studies that evaluate fixation, clinical function and implant survival, and patient-reported outcome scores, all of which were beyond the scope of this preliminary report.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Dislocation is one of the most common complications after revision THA. Dual-mobility constructs and large femoral heads (ie, 40 mm) are two contemporary, nonconstrained bearing options used in revision THA to minimize the risk of dislocation; however, it is not currently established if there is a clear benefit to using dual-mobility constructs over large femoral heads in the revision setting.Questions/purposes: We sought to determine if dual-mobility constructs would provide a reduction in dislocation, rerevision for dislocation, and reoperation or other complications as compared with large femoral heads in revision THA.Methods: From 2011 to 2014, a series of 355 THAs underwent revision for any reason and received either a dual-mobility construct (146 THAs) or a 40-mm large femoral head (209 THAs). Indications for either construct were based on surgeon judgment; however, there is a preference to use dual-mobility constructs in patients believed to be at higher risk of dislocation. In the dual-mobility group, 20 of 146 (14%) were excluded because of loss of followup before 2 years or because they had a dual-mobility shell cemented into a preexisting acetabular component. In the large head group, 33 of 209 (16%) were lost to followup before 2 years. Followup in the dual-mobility group was 3.3 ± 0.8 years and followup in the large head group was 3.9 ± 0.9 years. Primary endpoints included dislocation, rerevisions for dislocation, and reoperations, which were determined through our institution's total joint registry and verified by individual patient chart review. Age and body mass index were not different with the numbers available between the groups, but there was a slight predominance of females in the dual-mobility group (52% [66 of 126] female) versus the 40-mm large head group (41% [72 of 176] female) (p = 0.05). Notably, 33% (41 of 126) of patients receiving the dual-mobility constructs had the index revision THA done for a diagnosis of recurrent dislocation versus 9% (17 of 176) in the 40-mm large head group. Mean effective head size in the dual-mobility group was 47 mm (range, 38-58 mm).Results: The subsequent frequency of dislocation in the dual-mobility construct group was less (3% [four of 126] dual-mobility versus 10% [17 of 176] in the 40-mm large head group; hazard ratio, 3.2 [1.1-9.4]; p = 0.03). Rerevision for dislocation in the dual-mobility construct group was less frequent (1% [one of 126] dual-mobility versus 6% [10 of 176] in the 40-mm large head group; hazard ratio, 7.1 [0.9-55.6]; p = 0.03). Reoperation for any cause in the dual-mobility construct group was less frequent (6% [eight of 126] dual-mobility versus 15% [27 of 176] in the 40-mm large head group; hazard ratio, 2.5 [1.1-5.5]; p = 0.02); there were no differences between the groups in terms of the overall percentage of complications in each group.Conclusions: When compared with patients treated with a 40-mm large femoral head, patients undergoing revision THA who received a dual-mobility construct had a lower risk of subsequent dislocation, rerevision for dislocation, and reoperation for any reason in the first several years postoperatively. Those findings were present despite selection bias in this study to use the dual-mobility construct in patients at the highest risk for subsequent dislocation. Given the lower risk of subsequent dislocation, rerevision, and reoperation with the dual-mobility construct, some surgeons may wish to consider whether the role of dual-mobility should be judiciously expanded in contemporary revision THA.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: The choice of surgical approach for THA remains controversial. Some studies suggest that the direct anterior approach (DAA) leads to less muscle damage than the miniposterior approach (MPA), but there is little high-quality evidence indicating whether this accelerates recovery, or whether this approach-which may be technically more demanding-is associated with component malposition or more complications.Questions/purposes: (1) Does the DAA result in faster return to activities of daily living than the MPA? (2) Does the DAA have superior patient-reported outcome measures than the MPA? (3) Does the DAA result in improved radiographic outcomes than the MPA? (4) Does the DAA have a higher risk of complications than the MPA?Methods: Between March 1, 2013, and May 31, 2016, 116 patients undergoing primary unilateral THA were randomized to either the DAA or MPA; 15 patients withdrew after randomization, and one died 6 months after surgery from a stroke unrelated to the procedure. Recruitment stopped when 52 patients had been randomized into the DAA group and 49 in the MPA group (n = 101). After patient randomization, one high-volume surgeon performed all of the DAAs and three high-volume surgeons performed the MPA THAs. The groups did not differ in age (65 years; SD 11; range, 38-86 years), sex (52% women), or body mass index (mean 29 kg/m; SD 6 kg/m; range, 21-40 kg/m; all p > 0.40). Functional results included time to discontinue gait aids, discontinue all narcotics, and independence with various activities of daily living; accelerometer data evaluated activity level. Clinical and radiographic outcomes, Hip disability and Osteoarthritis Outcome Score, SF-12, and Harris hip scores to 1 year were also tabulated. The minimum followup was 365 days (mean ± SD, 627 ± 369 days).Results: There were slight differences in early functional recovery that favored the DAA versus the MPA: time to discontinue walker use (10 versus 15 days, p = 0.01) and time to discontinue all gait aids (17 versus 24 days, p = 0.04). There were no other differences in early functional milestones, although at 2 weeks after surgery, mean steps per day were 3897 (SD 2258; range, 737-11,010) for the DAA versus 2235 for the MPA (SD 1688; range, 27-7450; p < 0.01). There was no difference in activity monitoring at 1 year. There were no differences in patient-reported outcome scores between the groups. There was no difference in the radiographic parameters measured in the two groups, including leg length discrepancy, component position, or offset, and there was no subsidence observed in any hip. There was no difference in complications between the DAA and the MPA groups (8% [four of 52] versus 10% [five of 49]; p = 0.33).Conclusions: Both the DAA and MPA approaches provided excellent early recovery with a low risk of complications. Patients undergoing the DAA had a slightly faster recovery, as measured by milestones of function and quantified by activity monitor data, but no substantive differences were evident at 2 months. Because the DAA is the less studied approach, longer term (> 1 year) complications may yet accrue, will be important to quantify, and may offset early benefits.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Previously published studies reported benefits of computer-assisted surgery (CAS) in terms of radiographic implant position in TKA, but whether these improvements result in clinically important survival differences or functional differences that a patient might perceive at a minimum 10-year followup remains largely unknown.Questions/purposes: We performed a prospective randomized trial and asked whether CAS (1) improved survival free from aseptic loosening; and (2) demonstrated any clear difference in patient-reported outcomes at latest followup using validated outcome measures at minimum 10-year followup.Methods: Between January 2004 and December 2005, 80 patients scheduled for TKA were randomly assigned either to the CAS group or to the conventional technique group by the Hospital Informatics Department. The patient inclusion criteria were age 20 to 80 years old, weight < 100 kg, and consent to receive a primary knee arthroplasty performed through a medial parapatellar approach by the senior author. The exclusion criteria were a history of prior knee surgery, TKA performed for a posttraumatic indication, or revision knee surgery. The first 80 patients meeting these criteria were included in the study. There were 21 women and 19 men and in each group; mean age was 66 years (range, 58-77 years), and mean body mass index was 27 ± 4 kg/m. An initial published study using this patient group investigated only differences regarding implant positioning in the coronal and sagittal planes. This is a secondary analysis of patients from the earlier study protocol at a minimum of 10-year followup with different endpoints. Kaplan-Meier survivorship was compared between groups, and functional patient-reported outcome measures (PROMs) were evaluated using the SF-12, Knee Injury and Osteoarthritis Outcome Score (KOOS), Forgotten Joint Score, and the new Knee Society Score. Those PROMs were not available at the time of the original randomized controlled trial and we therefore do not have baseline preoperative values demonstrating that our two groups were comparable. However, our groups were created using strict randomization and were similar in terms of demographic parameters and knee deformities. Our secondary analysis was not powered for survival analysis but had 80% power to detect a difference > 6 points on the SF-12 components and > 6 points out of 100 on the KOOS subscores (published minimal clinically important difference: 8 points) at the p < 0.05 level.Results: With the numbers available, there was no difference between the CAS group and the conventional TKA group in terms of survivorship free from aseptic loosening 10 years after TKA (97%, 95% confidence interval [CI], 95%-99% versus 97%, 95% CI, 95%-99%; p = 0.98). Investigation of the latest followup PROM scores showed no difference between SF-12 scores (respectively, for CAS and control patients, physical SF-12: 72 ± 12 versus 73 ± 13 mean difference 0, 95% CI -3 to 3, p = 0.9; mental SF-12: 75 ± 8 versus 73 ± 10, mean difference 2, 95% CI 0-4, p = 0.3) as well as for all KOOS subscores (all p > 0.1). Forgotten Joint Scores were similar in both groups with 83 ± 4 for CAS and 82 ± 5 for control patients (mean difference 1, 95% CI 0-2, p = 0.2). Finally, the new Knee Society Scores were not statistically different between groups with a mean objective score of 82 ± 13 for CAS patients versus 79 ± 12 for control patients (mean difference 2, 95% CI 0-5, p = 0.5) and a mean subjective score of 83 ± 11 versus 85 ± 12, respectively (mean difference 2, 95% CI 0-5, p = 0.5).Conclusions: Our observations suggest that CAS used for TKA alignment with restoration of a neutral mechanical axis as the goal did not confer any substantial advantage in survivorship, function, or quality of life at 10 years after TKA. Larger studies with longitudinal collection of PROMs for functional assessment and greater numbers to assess survivorship are needed to confirm these findings.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Controversy exists over the surgical treatment for severe patellofemoral osteoarthritis. We therefore wished to compare the outcome of patellofemoral arthroplasty (PFA) with TKA in a blinded randomized controlled trial.Questions/purposes: In the first 2 years after surgery: (1) Does the overall gain in quality of life differ between the implants based on the area under the curve of patient-reported outcomes (PROs) versus time? (2) Do patients obtain a better quality of life at specific points in time after PFA than after TKA? (3) Do patients get a better range of movement after PFA than after TKA? (4) Does PFA result in more complications than TKA?Methods: Patients were eligible if they had debilitating symptoms and isolated patellofemoral disease. One hundred patients were included from 2007 to 2014 and were randomized to PFA or TKA (blinded for the first year; blinded to patient, therapists, primary care physicians, etc; quasiblinded to assessor). Patients were seen for four clinical followups and completed six sets of questionnaires during the first 2 postoperative years. SF-36 bodily pain was the primary outcome. Other outcomes were range of movement, PROs (SF-36, Oxford Knee Score [OKS], Knee injury and Osteoarthritis Outcome Score [KOOS]) as well as complications and revisions. Four percent (two of 50) of patients died within the first 2 years in the PFA group (none in the TKA group), and 2% (one of 50) became ill and declined further participation after 1 year in the PFA group (none in the TKA group). The mean age at inclusion was 64 years (SD 8.9), and 77% (77 of 100) were women.Results: The area under the curve (AUC) up to 2 years for SF-36 bodily pain of patients undergoing PFA and those undergoing TKA was 9.2 (SD 4.3) and 6.5 (SD 4.5) months, respectively (p = 0.008). The SF-36 physical functioning, KOOS symptoms, and OKS also showed a better AUC up to 2 years for PFA compared with TKA (6.6 [SD 4.8] versus 4.2 [SD 4.3] months, p = 0.028; 5.6 [SD 4.1] versus 2.8 [SD 4.5] months, p = 0.006; 7.5 [SD 2.7] versus 5.0 [SD 3.6] months, p = 0.001; respectively). The SF-36 bodily pain improvement at 6 months for patients undergoing PFA and those undergoing TKA was 38 (SD 24) and 27 (SD 23), respectively (p = 0.041), and at 2 years, the improvement was 39 (SD 24) and 33 (SD 22), respectively (p = 0.199). The KOOS symptoms improvement at 6 months for patients undergoing PFA and those undergoing TKA was 24 (SD 20) and 7 (SD 21), respectively (p < 0.001), and at 2 years, the improvement was 27 (SD 19) and 17 (SD 21), respectively (p = 0.023). Improvements from baseline for KOOS pain, SF-36 physical functioning, and OKS also differed in favor of PFA at 6 months, whereas only KOOS symptoms showed a difference between the groups at 2 years. No PRO dimension showed a difference in favor of TKA. At 4 months, 1 year, and 2 years, the ROM change from baseline for patients undergoing PFA and those undergoing TKA was (-7° [SD 13°] versus -18° [SD 14°], p < 0.001; -4° [SD 15°] versus -11° [SD 12°], p = 0.011; and -3° [SD 12°] versus -10° [SD 12°], p = 0.010). There was no difference in the number of complications. During the first 2 postoperative years, there were two revisions in patients undergoing PFA (one to a new PFA and one to a TKA).Conclusions: Patients undergoing PFA obtain a better overall knee-specific quality of life than patients undergoing TKA throughout the first 2 years after operation for isolated patellofemoral osteoarthritis. At 2 years, only KOOS function differs between patients undergoing PFA and those undergoing TKA, whereas other PRO dimensions do not show a difference between groups. The observations can be explained by patients undergoing PFA recovering faster than patients undergoing TKA and the functional outcome being better for patients undergoing PFA up to 9 months. Patients undergoing PFA regain their preoperative ROM, whereas patients undergoing TKA at 2 years have lost 10° of ROM. We found no differences in complications.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: As length of stay decreases for total joint arthroplasty, much of the patient preparation and teaching previously done in the hospital must be performed before surgery. However, the most effective form of preparation is unknown. This randomized trial evaluated the effect of a one-time, one-on-one preoperative physical therapy education session coupled with a web-based microsite (preopPTEd) on patients' readiness to discharge from physical therapy (PT), length of hospital stay, and patient-reported functional outcomes after total joint arthroplasty.Questions/purposes: Was this one-on-one preoperative PT education session coupled with a web- based microsite associated with (1) earlier achievement of readiness to discharge from PT; (2) a reduced hospital length of stay; and (3) improved WOMAC scores 4 to 6 weeks after surgery?Methods: Between February and June 2015, 126 typical arthroplasty patients underwent unilateral TKA or THA. As per our institution's current guidelines, all patients attended a preoperative group education class taught by a multidisciplinary team comprising a nurse educator, social worker, and physical therapist. Patients were then randomized into two groups. One group (control; n = 63) received no further education after the group education class, whereas the intervention group (experimental; n = 63) received preopPTEd. The preopPTEd consisted of a one-time, one-on-one session with a physical therapist to learn and practice postoperative precautions, exercises, bed mobility, and ambulation with and negotiation of stairs. After this session, all patients in the preopPTEd group were given access to a lateralized, joint-specific microsite that provided detailed information regarding exercises, transfers, ambulation, and activities of daily living through videos, pictures, and text. Outcome measures assessed included readiness to discharge from PT, which was calculated by adding the number of postoperative inpatient PT visits patients had to meet PT milestones. Hospital length of stay (LOS) was assessed for hospital discharge criteria and 6-week WOMAC scores were gathered by study personnel. At our institution, to meet PT milestones for hospital discharge criteria, patients have to be able to (1) independently transfer in and out of bed, a chair, and a toilet seat; (2) independently ambulate approximately 150 feet; (3) independently negotiate stairs; and (4) be independent with a home exercise program and activities of daily living. Complete followup was available on 100% of control group patients and 100% patients in the intervention group for all three outcome measures (control and intervention of 63, respectively).Results: The preopPTEd group had fewer postoperative inpatient PT visits (mean, 3.3; 95% confidence interval [CI], 3.0-3.6 versus 4.4; 95% CI, 4.1-4.7; p < 0.001) and achieved readiness to discharge from PT faster (mean, 1.6 days; 95% CI, 1.2-1.9 days versus 2.7 days; 95% CI, 2.4-3.0; p < 0.001) than the control group. There was no difference in hospital LOS between the preopPTEd group and the control group (2.4 days; 95% CI, 2.1-2.6; p = 0.082 versus 2.6 days; 95% CI, 2.4-2.8; p = 0.082). There were no clinically relevant differences in 6-week WOMAC scores between the two groups.Conclusions: Although this protocol resulted in improved readiness to discharge from PT, there was no effect on LOS or WOMAC scores at 6 weeks. Preoperative PT was successful in improving one of the contributors to LOS and by itself is insufficient to make a difference in LOS. This study highlights the need for improvement in other aspects of care to improve LOS.Level Of Evidence: Level II, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: In 2012, a new Knee Society Knee Scoring System (KSS) was developed and validated to address the needs for a scoring system that better encompasses the expectations, satisfaction, and physical involvement of a younger, more active population of patients undergoing TKA. Revalidating this tool in a separate population by individuals other than the developers of the scoring system seems important, because such replication would tend to confirm the generalizability of this tool.Questions/purposes: The purposes of this study were (1) to validate the KSS using a separate sample of patients undergoing primary TKA; and (2) to evaluate the internal consistency of the KSS.Methods: Intervention and control groups from a randomized controlled trial with no between-group differences were pooled. Preoperative and postoperative (6 weeks and 1 year) data were used. Patients with osteoarthritis undergoing primary TKA completed the patient-reported component of the KSS, Knee Injury and Osteoarthritis Outcome Score (KOOS), SF-12, two independent questions about expectations of surgery, and the Patient Acceptable Symptom State (PASS) single-question outcome. This study included 345 patients with 221 (64%) women, an average (SD) age of 64 (8.6) years, a mean (SD) body mass index of 32.9 (7.5) kg/m, and 225 (68%) having their first primary TKA. Loss to followup in the control group was 18% and loss to followup in the intervention group was 13%. We quantified cross-sectional (preoperative scores) and longitudinal validity (pre- to postoperative change scores) by evaluating associations between the KSS and KOOS subscales using Spearman's correlation coefficient. Preoperative known-group validity of the KSS symptoms and functional activity score was evaluated with a one-way analysis of variance across three levels of physical health status using the SF-12 Physical Component Score. Known-group validity of the KSS expectation score was evaluated with an unpaired t-test by comparing means across known expectation groups. Known-group validity of the KSS satisfaction score was evaluated with an unpaired t-test by comparing means across yes/no response groupings of the PASS single-question outcome. Internal consistency for each KSS subscale was evaluated with Cronbach's α.Results: Cross-sectional validity (ie, associations at a single point in time) was supported because correlation coefficients between KSS symptoms, functional activities, and satisfaction scores and scores on the KOOS pain subscale ranged from 0.60 to 0.73 (all correlations p < 0.01). Values were similar for associations with the KOOS function in the activities of daily living (ADL) subscale (0.66-0.69) and less (0.41-0.58) for correlations with the other three KOOS subscales. Longitudinal validity (ie, associations of change scores between two time points) was also supported because correlation coefficients between KSS symptoms, functional activities, and satisfaction change scores and the KOOS pain and ADL change scores varied from 0.63 to 0.73. Correlation coefficients were lower for the other three KOOS subscale change scores, suggesting a weaker relationship with KOOS symptoms (0.48-0.53), sports (0.47-0.51), and quality of life (0.60-0.65) (all correlations p < 0.01). Known-group validity (ie, differences between groups that are known to differ on a given characteristic) was confirmed by between-group differences for the symptoms and functional activities score comparisons as well as the comparisons with the expectations and satisfaction scores of the KSS (all p < 0.01). Cronbach's α (ie, association among subscale items) varied from 0.68 (discretionary activities) to 0.94 (postoperative expectations) across four KSS subscales.Conclusions: Moderate-sized correlation coefficients and consistent differences between known groups support the validity of the KSS. Internal consistency values were also acceptable. The patient-reported subscales of the KSS are a valid and internally consistent outcome assessment for TKA. [ABSTRACT FROM AUTHOR]

Background: Proponents of computer-assisted TKA suggest that better alignment of the TKAs will lead to improved long-term patient functional outcome and survivorship of the implants. However, there is little evidence about whether the improved position and alignment of the knee components obtained using computer navigation improve patient function and the longevity of the TKA.Questions/purposes: The purpose of this study was to determine whether (1) clinical results; (2) radiographic and CT scan results; and (3) the survival rate of TKA components would be better in patients having computer-assisted TKA than results of patients having TKA without computer-assisted TKA. In addition, we determined whether (4) complication rates would be less in the patients with computer-assisted TKA than those in patients with conventional TKA.Methods: We performed a randomized trial between October 2000 and October 2002 in patients undergoing same-day bilateral TKA; in this trial, one knee was operated on using navigation, and the other knee was operated on without navigation. All 296 patients who underwent same-day bilateral TKA during that period were enrolled. Of those, 282 patients (95%) were accounted for at a mean of 15 years (range, 14-16 years). A total of 79% (223 of 282) were women and the mean age of the patients at the time of index arthroplasty was 59 ± 7 years (range, 48-64 years). Knee Society knee score, WOMAC score, and UCLA activity score were obtained preoperatively and at latest followup. Radiographic measurements were performed including femorotibial angle, position of femoral and tibial components, level of joint line, and posterior condylar offset. Aseptic loosening was defined as a complete radiolucent line > 1 mm in width around any component or migration of any component. Assessors and patients were blind to treatment assignment.Results: The Knee Society knee (92 ± 8 versus 93 ± 7 points; 95% confidence interval [CI], 92-98; p = 0.461) and function scores (80 ± 11 versus 80 ± 11 points; 95% CI, 73-87; p = 1.000), WOMAC score (14 ± 7 versus 15 ± 8 points; 95% CI, 14-18; p = 0.991), range of knee motion (128° ± 9° versus 127° ± 10°; 95% CI, 100-140; p = 0.780), and UCLA patient activity score (6 versus 6 points; 95% CI, 4-8; p = 1.000) were not different between the two groups at 15 years followup. There were no differences in any radiographic parameters of alignment (on radiography or CT scan) between the two groups. The frequency of aseptic loosening was not different between the two groups (p = 0.918). Kaplan-Meier survivorship of the TKA components was 99% in both groups (95% CI, 93-100) at 15 years as the endpoint of revision or aseptic loosening (p = 0.982). Anterior femoral notching was observed in 11 knees (4%) in the computer-assisted TKA group and none in the conventional TKA group (p = 0.046).Conclusions: In this randomized trial, with data presented at a minimum of 14 years of followup, we found no benefit to computer navigation in TKA in terms of pain, function, or survivorship. Unless another study at long-term followup identifies an advantage to survivorship, pain, and function, we do not recommend the widespread use of computer navigation in TKA because of its risks (in this series, we observed femoral notching; others have observed pin site fractures) and attendant costs.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Clinical weightbearing provocation tests, like the duck walk test, may be of value in diagnosing or screening for medial meniscal tears. However, evidence of the diagnostic accuracy of the duck walk test is lacking.Questions/purposes: (1) To determine the sensitivity and specificity of the duck walk test in diagnosing medial meniscal tears. (2) To determine whether tear location, tear cause (traumatic versus degenerative), and ACL insufficiency were associated with differences in the sensitivity and specificity of the test.Methods: A convenience sample of 136 patients of all ages was retrospectively analyzed by evaluating the outpatient knee clinic appointment list of one orthopaedic surgeon for patients with a broad range of knee injuries who had a prior MRI before (24%) or after (76%) physical examination and had a duck walk test stated in their patient records. Of 230 patients with MRI requested by one orthopaedic surgeon attributable to knee complaints, 136 (59%) fulfilled the inclusion criteria; 70 (52%) patients were male and 66 (49%) were female, with a mean age of 42 (± SD 14) years. The duck walk test was performed in case of suspected meniscal injury, based on mechanism of injury, general joint line pain, and/or mechanical complaints (ie, locking, giving away). The test is performed by squatting and "waddling" before rising and is positive in case of general joint line pain or painful "clicking". Interobserver repeatability was not evaluated, but the test is well defined and leaves little room for difference in interpretation. Diagnostic accuracy measures were evaluated. Since the convenience sample in this study consisted of patients who had a duck walk test and MRI, and a positive result of the duck walk test almost certainly increased the probability that MRI would be ordered in the majority (76%) of the patients, the test properties calculated here-especially sensitivity-should be considered inflated.Results: The calculated sensitivity of the duck walk test was 71% (95% CI, 59%-81%) and there was low specificity of 39% (95% CI, 27%-52%). We found no difference in sensitivity between medial (67%; 95% CI, 51%-80%) and lateral (76%; 95% CI, 50%-92%; p = 0.492) meniscal tears. With the numbers available, we compared these patients with patients without a history of trauma and with an intact ACL. We found no difference among patients with traumatic tears (79%; 95% CI, 59%-91%; p = 0.253) and in patients with ACL tears (77%; 95% CI, 46%-94%; p = 0.742).Conclusions: Because of the issue of verification bias, the actual sensitivity of this test in practice is likely much lower than the calculated sensitivity we observed. In addition, the test did not seem to perform better in patients with trauma or ACL insufficiency, nor was it more effective in detecting medial than lateral tears, although the numbers on some of those comparisons were rather small. Based on these results, we conclude that used alone, the duck walk test likely has little value in practice as a screening test. However, it is conceivable that it could be used in combination with other provocative tests for screening purposes. Future studies might consider using it as a means to best identify which patients should undergo MRI for the possibility of a meniscal tear.Level Of Evidence: Level III, diagnostic study. [ABSTRACT FROM AUTHOR]

Background: Tibial baseplate roughness and polyethylene-insert micromotion resulting from locking-mechanism loosening can lead to polyethylene backside wear in TKAs. However, many retrieval studies examining these variables have evaluated only older TKA implant designs.Questions: We used implant-retrieval analysis to examine if there were differences in: (1) backside damage scores, (2) backside damage modes, and (3) backside linear wear rates in five TKA implant designs owing to differing baseplate surface roughness and locking mechanisms. Additionally, we examined if (4) patient demographics influence backside damage and wear.Methods: Five TKA implant models (four modern and one historical design) were selected with different tibial baseplate and/or locking mechanism designs. Six tibial inserts retrieved at the time of revision from each TKA model were matched for time in vivo, age of the patient at TKA revision, BMI, sex, revision number, and revision reason. Each insert backside was analyzed for: (1) visual total damage score and (2) individual visual damage modes, both by two observers and with an intraclass correlation coefficient of 0.66 (95% CI, 0.39-0.92), and (3) linear wear rate measured by micro-CT. Median primary outcomes were compared among the five designs. For our given sample size among five groups we could detect with 80% power a 10-point difference in damage score and an 0.11-mm per year difference in wear rate.Results: The polished tibial design with a partial peripheral capture locking mechanism and anterior constraint showed a lower total damage score compared with the nonpolished tibial design with only a complete peripheral-rim locking mechanism (median, 12.5; range, 9.5-18.0; 95% CI, 9.58-16.42 versus median, 22.3; range, 15.5-27.0; 95% CI, 17.5-26.5; p = 0.019). The polished baseplate with a tongue-in-groove locking mechanism showed more abrasions than the nonpolished baseplate with a peripheral-rim capture and antirotational island (median, 7.25; range, 0.5-8.0; 95% CI, 2.67-8.99 versus median, 0.75; range, 0-1.5; 95% CI, 0.20-1.47; p = 0.016)). Dimpling was a unique wear mode to the nonpolished baseplates with the peripheral-rim capture and antirotational island (median, 5.5; range, 2.0-9.0; 95% CI, 2.96-8.38) and the peripheral-rim capture alone (median, 9.0; range, 6.0-10.0; 95% CI, 7.29-10.38). Overall, the linear wear rate for polished designs was lower than for nonpolished designs (0.0102 ± 0.0044 mm/year versus 0.0224 ± 0.0119 mm/year; p < 0.001). Two of the polished baseplate designs, the partial peripheral capture with anterior constraint (median, 0.083 mm/year; range, 0.0037-0.0111 mm/year; 95% CI, 0.0050-0.0107 mm versus median, 0.0245 mm/year; range, 0.014-0.046 mm/year; 95% CI, 0.0130-0.0414 mm; p = 0.008) and the tongue-in-groove locking mechanism (median, 0.0085 mm/year; range, 0.005-0.015 mm/year; 95% CI, 0.0045-0.0138 mm; p = 0.032) showed lower polyethylene linear wear rates compared with the nonpolished baseplate design with only a peripheral-rim capture.Conclusions: Total damage scores and linear wear rates were highest involving the nonpolished design with only a peripheral rim capture. There were no differences among the other TKA designs regarding damage and wear, but this finding should be considered in the setting of a relatively small sample size.Clinical Relevance: Our study showed that in the complex interplay between baseplate surface finish and locking mechanism design, a polished baseplate with a robust locking mechanism had the lowest backside damage and linear wear. However, improvements in locking mechanism design in nonpolished baseplates potentially may offset some advantages of a polished baseplate. Further retrieval analyses need to be done to confirm such findings, especially analyzing current crosslinked polyethylene. Additionally, we need mid- and long-term studies comparing TKA revisions attributable to wear and osteolysis among implants before understanding if such design differences are clinically relevant. [ABSTRACT FROM AUTHOR]

Background: With the increasing number of patients with knee osteoarthritis undergoing TKAs in China, there is a clear need for a valid, short, joint-specific patient-reported outcome measure such as the Oxford Knee Score (OKS).Questions/purposes: To test the translated and cross-culturally adapted Chinese (Mandarin) version of the Oxford Knee Score (OKS-CV) and its (1) reliability, (2) construct validity, (3) dimensionality, and (4) responsiveness.Methods: Three native Chinese bilingual translators (a professional English translator, an experienced orthopaedic surgeon, an advanced-practice nursing specialist) translated the English-language OKS into Mandarin Chinese. A consensus panel created a synthesis of those efforts, which then was back-translated by two bilingual nonmedical, professional English-language translators. The OKS-CV was developed according to the guidelines of copyright holders. Between March 2013 and March 2015, 253 patients underwent TKAs. Among them, 114 Mandarin-speaking patients with knee osteoarthritis underwent primary unilateral TKA (age, 67 ± 7 years; range, 55-84 years; female, 80%; preoperatively 54% had moderate to severe knee osteoarthritis), completed the preoperative questionnaires, and were followed up, with a mean postoperative followup of 2.7 years (SD, 0.5 years). Eligibility criteria were (1) patients with knee osteoarthritis who were scheduled to have a primary unilateral TKA, (2) patients who were fluent in Mandarin, and (3) consent to participate. The exclusion criteria were: (1) lack of understanding of Mandarin, and (2) inability to comprehend the questionnaires owing to cognitive impairment. To evaluate test-retest reliability, another group of 35 Mandarin-speaking outpatients with knee osteoarthritis (age, 61 ± 10 years; range, 44-84 years; female, 77%) was recruited to complete the OKS-CV twice at a 1-week interval. Reliability was tested using Cronbach's alpha and intraclass correlation coefficient (ICC). Construct validity was evaluated using Spearman's rank correlation coefficient to quantify the correlations between the OKS-CV and the WOMAC, Short Form-8 Health Survey (SF-8TM), and EuroQol Group 5-Dimension Self-Report Questionnaire (EQ-5D). Exploratory factor analysis was performed to clarify dimensionality. The eigenvalue indicates the importance of each factor obtained from factor analysis. Responsiveness was determined by standardized response mean (SRM) and effect size (ES) from preoperative and postoperative scores of the OKS-CV. Floor and ceiling effects also were analyzed.Results: The internal consistency (Cronbach's alpha = 0.89) and test-retest reliability (ICC = 0.93; 95% CI, 0.87-0.97) proved good. Convergent construct validity was supported by moderate to strong correlations between the OKS-CV and the WOMAC (r = -0.80, p < 0.001), the SF-8TM physical component summary (r = 0.65, p < 0.001), and the EQ-5D usual activities (r = -0.41, p < 0.001) and mobility (r = -0.35, p < 0.001). There also were correlations between the OKS-CV and the SF-8TM mental component summary (r = 0.58, p < 0.001) and the EQ-5D anxiety/depression (r = -0.35, p < 0.001). The factor analysis yielded three factors with eigenvalues greater than 1. Responsiveness was excellent (SRM = 1.52; ES = 1.52). No floor or ceiling effect was observed.Conclusions: The OKS-CV showed good acceptability and psychometric properties for the intended population. Future studies are needed to evaluate the mental state of patients with knee osteoarthritis.Clinical Relevance: The OKS-CV appears to be a reliable, valid, and responsive instrument for Chinese patients with knee osteoarthritis. Based on these results we believe the OKS-CV can be used as a valuable tool for the assessment of patient-reported outcomes in Chinese patients with knee osteoarthritis before and after TKA. [ABSTRACT FROM AUTHOR]

Background: Traditional patient-reported outcome instruments like the Foot and Ankle Ability Measure (FAAM) quantify patient disability but often are limited by responder burden and incomplete questionnaires. The Patient-Reported Outcome Measurement Information System (PROMIS) overcomes such obstacles through computer-adaptive technology and can capture outcome data from various domains including physical and psychosocial function. Prior work has compared the FAAM with PROMIS physical function; however, there is little evidence comparing the association between foot and ankle-specific tools like the FAAM with more general outcomes measures of PROMIS pain interference and depression in foot and ankle conditions.Questions/purposes: (1) We asked whether there was a relationship between FAAM Activities of Daily Living (ADL) scores with PROMIS physical function, pain interference, and depression in patients with hallux valgus. (2) Additionally, we asked if we could identify specific factors that are associated with variance in FAAM and PROMIS physical function scores in patients with hallux valgus.Methods: Eighty-five new patients with either a primary or secondary diagnosis of hallux valgus based on clinic billing codes from July 2015 to February 2016 were retrospectively identified. Patients completed FAAM ADL paper-based surveys and electronic PROMIS questionnaires for physical function, pain interference, and depression from new patient visits at a single time. Spearman rho correlations were performed between FAAM ADL and PROMIS scores. Analyses then were used to identify differences in FAAM ADL and PROMIS physical function measures based on demographic variables. Stepwise linear regressions then determined which demographic and/or outcome variable(s) accounted for the variance in FAAM ADL and PROMIS physical function scores.Results: FAAM scores correlated strongly with PROMIS physical function (r = 0.70, p < 0.001), moderately with PROMIS pain interference (r = -0.65, p < 0.001), and weakly with PROMIS depression (r = -0.35, p < 0.001) scores. Regression analyses showed that PROMIS pain interference scores alone were associated with sizeable portions of the variance in FAAM ADL (R2 = 0.44, p < 0.001) and PROMIS physical function (R2 = 0.57, p < 0.001) measures.Conclusions: PROMIS function and pain measures correlated with FAAM ADL scores, highlighting the interrelationship of pain and function when assessing outcomes in patients with hallux valgus. PROMIS tools allow for more-efficient data collection across multiple domains and, moving forward, may be better poised to monitor changes in pain and function with time compared with traditional outcome measures like the FAAM.Clinical Relevance: The relationships shown here between PROMIS and FAAM scores further support the use of PROMIS tools in outcomes-based research. In patients with hallux valgus, pain-related disability appears to be a central feature of the patient-experience. Future studies should assess the association of various outcome domains on other common foot and ankle diagnoses. [ABSTRACT FROM AUTHOR]

Background: The FIFA 11+ injury prevention program has been shown to decrease the risk of soccer injuries in men and women. The program has also been shown to decrease time loss resulting from injury. However, previous studies have not specifically investigated how the program might impact the rate of anterior cruciate ligament (ACL) injury in male soccer players.Questions/purposes: The purpose of this study was to examine if the FIFA 11+ injury prevention program can (1) reduce the overall number of ACL injuries in men who play competitive college soccer and whether any potential reduction in rate of ACL injuries differed based on (2) game versus practice setting; (3) player position; (4) level of play (Division I or II); or (5) field type.Methods: This study was a prospective cluster randomized controlled trial, which was conducted in 61 Division I and Division II National Collegiate Athletic Association men's soccer teams over the course of one competitive soccer season. The FIFA 11+ is a 15- to 20-minute on-the-field dynamic warm-up program used before training and games and was utilized as the intervention throughout the entire competitive season. Sixty-five teams were randomized: 34 to the control group (850 players) and 31 to the intervention group (675 players). Four intervention teams did not complete the study and did not submit their data, noting insufficient time to complete the program, reducing the number for per-protocol analysis to 61. Compliance to the FIFA 11+ program, athletic exposures, specific injuries, ACL injuries, and time loss resulting from injury were collected and recorded using a secure Internet-based system. At the end of the season, the data in the injury surveillance system were crosshatched with each individual institution's internal database. At that time, the certified athletic trainer signed off on the injury collection data to confirm their accuracy and completeness.Results: A lower proportion of athletes in the intervention group experienced knee injuries (25% [34 of 136]) compared with the control group (75% [102 of 136]; relative risk [RR], 0.42; 95% confidence interval [CI], 0.29-0.61; p < 0.001). When the data were stratified for ACL injury, fewer ACL injuries were reported in the intervention group (16% [three of 19]) compared with the control group (84% [16 of 19]), accounting for a 4.25-fold reduction in the likelihood of incurring ACL injury (RR, 0.236; 95% CI, 0.193-0.93; number needed to treat = 70; p < 0.001). With the numbers available, there was no difference between the ACL injury rate within the FIFA 11+ group and the control group with respect to game and practice sessions (games-intervention: 1.055% [three of 15] versus control: 1.80% [12 of 15]; RR, 0.31; 95% CI, 0.09-1.11; p = 0.073 and practices-intervention: 0% [zero of four] versus control: 0.60% [four of four]; RR, 0.14; 95% CI, 0.01-2.59; p = 0.186). With the data that were available, there were no differences in incidence rate (IR) or injury by player position for forwards (IR control = 0.339 versus IR intervention = 0), midfielders (IR control = 0.54 versus IR intervention = 0.227), defenders (IR control = 0.339 versus IR intervention = 0.085), and goalkeepers (IR control = 0.0 versus IR intervention = 0.0) (p = 0.327). There were no differences in the number of ACL injuries for the Division I intervention group (0.70% [two of nine]) compared with the control group (1.05% [seven of nine]; RR, 0.30; CI, 0.06-1.45; p = 0.136). However, there were fewer ACL injuries incurred in the Division II intervention group (0.35% [one of 10]) compared with the control group (1.35% [nine of 10]; RR, 0.12; CI, 0.02-0.93; p = 0.042). There was no difference between the number of ACL injuries in the control group versus in the intervention group that occurred on grass versus turf (Wald chi square [1] = 0.473, b = 0.147, SE = 0.21, p = 0.492). However, there were more ACL injuries that occurred on artificial turf identified in the control group (1.35% [nine of 10]) versus the intervention group (0.35% [one of 10]; RR, 0.14; 95% CI, 0.02-1.10; p = 0.049).Conclusions: This program, if implemented correctly, has the potential to decrease the rate of ACL injury in competitive soccer players. In addition, this may also enhance the development and dissemination of injury prevention protocols and may mitigate risk to athletes who utilize the program consistently. Further studies are necessary to analyze the cost-effectiveness of the program implementation and to analyze the efficacy of the FIFA 11+ in the female collegiate soccer cohort.Level Of Evidence: Level I, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Movement asymmetries during walking are common after anterior cruciate ligament (ACL) injury and reconstruction and may influence the early development of posttraumatic osteoarthritis. Preoperative neuromuscular training (like perturbation training, which is neuromuscular training requiring selective muscle activation in response to surface perturbations) improves gait asymmetries and functional outcomes among people who are ACL-deficient, but the effect of postoperative perturbation training on gait mechanics after ACL reconstruction is unknown.Questions/purposes: Among men undergoing ACL reconstruction, we sought to compare strength, agility, and secondary prevention (SAP) treatment with SAP plus perturbation training (SAP+PERT) with respect to (1) gait mechanics; and (2) elimination of gait asymmetries 1 and 2 years after ACL reconstruction.Methods: Forty men were randomized into a SAP group or a SAP+PERT group after ACL reconstruction and before returning to preinjury activities. Participants were required to achieve ≥ 80% quadriceps muscle strength symmetry, minimal knee effusion, full ROM, no reports of pain, and completion of a running progression (all between 3 and 9 months postoperatively) before enrollment. Of 94 potentially eligible athletic male patients evaluated < 9 months after ACL reconstruction, 54 were excluded for prespecified reasons. Participants underwent motion analysis during overground walking at 1 and 2 years postoperatively. Variables of interest included (1) sagittal and frontal plane hip and knee angles and moments at peak knee flexion angle; (2) sagittal plane hip and knee angles and moments at peak knee extension angle; (3) sagittal plane hip and knee excursion during weight acceptance; and (4) sagittal plane hip and knee excursion during midstance. We also calculated the proportion of athletes in each group who walked with clinically meaningful interlimb asymmetry in sagittal plane hip and knee variables and compared these proportions using odds ratios. There was no differential loss to followup between groups.Results: There were no differences between the SAP or SAP+PERT groups for the biomechanical gait variables. The involved limb's knee excursion during midstance for the SAP (mean ± SD: 1 year: 15° ± 5°; 2 years: 16° ± 5°) and SAP+PERT (1 year: 16° ± 5°; 2 years: 15° ± 4°) athletes was not different between groups at 1 year (mean difference: -1°; 95% confidence interval [CI], -5° to 2°; p = 0.49) or 2 years (mean difference: 1°; 95% CI, -2° to 4°; p = 0.54). There were no differences between SAP and SAP+PERT athletes regarding the elimination of gait asymmetries, and gait asymmetries persisted to a large degree in both groups 1 and 2 years postoperatively. At 1 year, 11 of 18 SAP and 11 of 20 SAP+PERT athletes walked with truncated knee excursions during weight acceptance (odds ratio: 0.8, p = 0.70) and midstance (SAP 12 of 18, SAP+PERT 12 of 20; odds ratio: 0.8, p = 0.67), whereas at 2 years postoperatively, truncated knee excursions during weight acceptance (SAP seven of 17, SAP+PERT eight of 19; odds ratio: 1.0, p = 0.96) and midstance (SAP five of 17, SAP+PERT 11 of 19; odds ratio: 3.3, p = 0.09) remained prevalent.Conclusions: We found that a comprehensive, progressive return-to-sport training program with or without perturbation was not effective at restoring interlimb symmetry among men 1 or 2 years after ACL reconstruction. Although gait asymmetries improved from 1 to 2 years postoperatively, meaningful asymmetries persisted in both groups. To restore gait symmetry after ACL reconstruction, additional interventions likely are necessary.Level Of Evidence: Level II, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Athletes often are cleared to return to activities 6 months after anterior cruciate ligament (ACL) reconstruction; however, knee function measures continue to improve up to 2 years after surgery. Interventions beyond standard care may facilitate successful return to preinjury activities and improve functional outcomes. Perturbation training has been used in nonoperative ACL injury and preoperative ACL reconstruction rehabilitation, but has not been examined in postoperative ACL reconstruction rehabilitation, specifically return to sport rehabilitation.Questions/purposes: The purpose of this study was to determine whether there were differences at 1 and 2 years after ACL reconstruction between the male SAP (strengthening, agility, and secondary prevention) and SAP+PERT (SAP protocol with the addition of perturbation training) groups with respect to (1) quadriceps strength and single-legged hop limb symmetry; (2) patient-reported knee outcome scores; (3) the proportion who achieve self-reported normal knee function; and (4) the time from surgery to passing return to sport criteria.Methods: Forty men who had completed ACL reconstruction rehabilitation and met enrollment criteria (3-9 months after ACL reconstruction, > 80% quadriceps strength limb symmetry, no pain, full ROM, minimal effusion) were randomized into the SAP or SAP+PERT groups of the Anterior Cruciate Ligament-Specialised Post-Operative Return to Sports trial (ACL-SPORTS), a single-blind randomized clinical study of secondary prevention and return to sport. Quadriceps strength, single-legged hopping, the International Knee Documentation Committee (IKDC) 2000 subjective knee form, Knee Injury and Osteoarthritis Outcome Score (KOOS)-sports and recreation, and KOOS-quality-of-life subscales were collected 1 and 2 years after surgery by investigators blind to group. Athletes were categorized as having normal or abnormal knee function at each time point based on IKDC score, and the time until athletes passed strict return-to-sport criteria was also recorded. T-tests, chi square tests, and analyses of variance were used to identify differences between the treatment groups over time.Results: There were no differences between groups for quadriceps symmetry (1 year: SAP = 101% ± 14%, SAP+PERT = 101% ± 14%; 2 years: SAP = 103% ± 11%, SAP+PERT = 98% ± 14%; mean differences between groups at 1 year: 0.4 [-9.0 to 9.8], 2 years = 4.5 [-4.3 to 13.1]; mean difference between 1 and 2 years: SAP = -1.0 [-8.6 to 6.6], SAP+PERT = 3.0 [-4.3 to 10.3], p = 0.45) or single-legged hop test limb symmetry. There were no clinically meaningful differences for any patient-reported outcome measures. There was no difference in the proportion of athletes in each group who achieved normal knee function at 1 year (SAP 14 of 19, SAP+PERT 18 of 20, odds ratio 0.31 [0.5-19.0]; p = 0.18); however, the SAP+PERT group had fewer athletes with normal knee function at 2 years (SAP 17 of 17, SAP+PERT 14 of 19, p = 0.03). There were no differences between groups in the time to pass return to sport criteria (SAP = 325 ± 199 days, SAP+PERT = 233 ± 77 days; mean difference 92 [-9 to 192], p = 0.09).Conclusions: This randomized trial found few differences between an ACL rehabilitation program consisting of strengthening, agility, and secondary prevention and one consisting of those elements as well as perturbation training. In the absence of clinically meaningful differences between groups in knee function and self-reported outcomes measures, the results indicate that perturbation training may not contribute additional benefit to the strengthening, agility, and secondary prevention base of the ACL-SPORTS training program.Level Of Evidence: Level II, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Total ankle arthroplasty (TAA) is an alternative to arthrodesis, but no randomized trial has examined whether a fixed bearing or mobile bearing implant provides improved gait mechanics.Questions/purposes: We wished to determine if fixed- or mobile-bearing TAA results in a larger improvement in pain scores and gait mechanics from before surgery to 1 year after surgery, and to quantify differences in outcomes using statistical analysis and report the standardized effect sizes for such comparisons.Methods: Patients with end-stage ankle arthritis who were scheduled for TAA between November 2011 and June 2013 (n = 40; 16 men, 24 women; average age, 63 years; age range, 35-81 years) were prospectively recruited for this study from a single foot and ankle orthopaedic clinic. During this period, 185 patients underwent TAA, with 144 being eligible to participate in this study. Patients were eligible to participate if they were able to meet all study inclusion criteria, which were: no previous diagnosis of rheumatoid arthritis, a contralateral TAA, bilateral ankle arthritis, previous revision TAA, an ankle fusion revision, or able to walk without the use of an assistive device, weight less than 250 pounds (114 kg), a sagittal or coronal plane deformity less than 15°, no presence of avascular necrosis of the distal tibia, no current neuropathy, age older than 35 years, no history of a talar neck fracture, or an avascular talus. Of the 144 eligible patients, 40 consented to participate in our randomized trial. These 40 patients were randomly assigned to either the fixed (n = 20) or mobile bearing implant group (n = 20). Walking speed, bilateral peak dorsiflexion angle, peak plantar flexion angle, sagittal plane ankle ROM, peak ankle inversion angle, peak plantar flexion moment, peak plantar flexion power during stance, peak weight acceptance, and propulsive vertical ground reaction force were analyzed during seven self-selected speed level walking trials for 33 participants using an eight-camera motion analysis system and four force plates. Seven patients were not included in the analysis owing to cancelled surgery (one from each group) and five were lost to followup (four with fixed bearing and one with mobile bearing implants). A series of effect-size calculations and two-sample t-tests comparing postoperative and preoperative increases in outcome variables between implant types were used to determine the differences in the magnitude of improvement between the two patient cohorts from before surgery to 1 year after surgery. The sample size in this study enabled us to detect a standardized shift of 1.01 SDs between group means with 80% power and a type I error rate of 5% for all outcome variables in the study.Results: This randomized trial did not reveal any differences in outcomes between the two implant types under study at the sample size collected. In addition to these results, effect size analysis suggests that changes in outcome differ between implant types by less than 1 SD. Detection of the largest change score or observed effect (propulsive vertical ground reaction force [Fixed: 0.1 ± 0.1; 0.0-1.0; Mobile: 0.0 ± 0.1; 0.0-0.0; p = 0.0.051]) in this study would require a future trial to enroll 66 patients. However, the smallest change score or observed effect (walking speed [Fixed: 0.2 ± 0.3; 0.1-0.4; Mobile: 0.2 ± 0.3; 0.0-0.3; p = 0.742]) requires a sample size of 2336 to detect a significant difference with 80% power at the observed effect sizes.Conclusions: To our knowledge, this is the first randomized study to report the observed effect size comparing improvements in outcome measures between fixed and mobile bearing implant types. This study was statistically powered to detect large effects and descriptively analyze observed effect sizes. Based on our results there were no statistically or clinically meaningful differences between the fixed and mobile bearing implants when examining gait mechanics and pain 1 year after TAA.Level Of Evidence: Level II, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Double-bundle anterior cruciate ligament (ACL) reconstruction has demonstrated improved biomechanical properties and moderately better objective outcomes compared with single-bundle reconstructions. This could make an impact on the rerupture rate and reduce the risk of revisions in patients undergoing double-bundle ACL reconstruction compared with patients reconstructed with a traditional single-bundle technique. The National Knee Ligament Registers in Scandinavia provide information that can be used to evaluate the revision outcome after ACL reconstructions.Questions/purposes: The purposes of the study were (1) to compare the risk of revision between double-bundle and single-bundle reconstructions, reconstructed with autologous hamstring tendon grafts; (2) to compare the risk of revision between double-bundle hamstring tendon and single-bundle bone-patellar tendon-bone autografts; and (3) to compare the hazard ratios for the same two research questions after Cox regression analysis was performed.Methods: Data collection of primary ACL reconstructions from the National Knee Ligament Registers in Denmark, Norway, and Sweden from July 1, 2005, to December 31, 2014, was retrospectively analyzed. A total of 60,775 patients were included in the study; 994 patients were reconstructed with double-bundle hamstring tendon grafts, 51,991 with single-bundle hamstring tendon grafts, and 7790 with single-bundle bone-patellar tendon-bone grafts. The double-bundle ACL-reconstructed patients were compared with the two other groups. The risk of revision for each research question was detected by the risk ratio, hazard ratio, and the corresponding 95% confidence intervals. Kaplan-Meier analysis was used to estimate survival at 1, 2, and 5 years for the three different groups. Furthermore, a Cox proportional hazard regression model was applied and the hazard ratios were adjusted for country, age, sex, meniscal or chondral injury, and utilized fixation devices on the femoral and tibial sides.Results: There were no differences in the crude risk of revision between the patients undergoing the double-bundle technique and the two other groups. A total of 3.7% patients were revised in the double-bundle group (37 of 994 patients) versus 3.8% in the single-bundle hamstring tendon group (1952 of 51,991; risk ratio, 1.01; 95% confidence interval (CI), 0.73-1.39; p = 0.96), and 2.8% of the patients were revised in the bone-patellar tendon-bone group (219 of the 7790 bone-patellar tendon-bone patients; risk ratio, 0.76; 95% CI, 0.54-1.06; p = 0.11). Cox regression analysis with adjustment for country, age, sex, menisci or cartilage injury, and utilized fixation device on the femoral and tibial sides, did not reveal any further difference in the risk of revision between the single-bundle hamstring tendon and double-bundle hamstring tendon groups (hazard ratio, 1.18; 95% CI, 0.85-1.62; p = 0.33), but the adjusted hazard ratio showed a lower risk of revision in the single-bundle bone-patellar tendon-bone group compared with the double-bundle group (hazard ratio, 0.62; 95% CI, 0.43-0.90; p = 0.01). Comparisons of the graft revision rates reported separately for each country revealed that double-bundle hamstring tendon reconstructions in Sweden had a lower hazard ratio compared with the single-bundle hamstring tendon reconstructions (hazard ratio, 1.00 versus 1.89; 95% CI, 1.09-3.29; p = 0.02). Survival at 5 years after index surgery was 96.0% for the double-bundle group, 95.4% for the single-bundle hamstring tendon group, and 97.0% for the single-bundle bone-patellar tendon-bone group.Conclusions: Based on the data from all three national registers, the risk of revision was not influenced by the reconstruction technique in terms of using single- or double-bundle hamstring tendons, although national differences in survival existed. Using bone-patellar tendon-bone grafts lowered the risk of revision compared with double-bundle hamstring tendon grafts. These findings should be considered when deciding what reconstruction technique to use in ACL-deficient knees. Future studies identifying the reasons for graft rerupture in single- and double-bundle reconstructions would be of interest to understand the findings of the present study.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Large Achilles tendon defects pose a treatment challenge. The standard treatment with a turndown flap requires a large extensile incision, puts the sural nerve at risk, and demands slow, careful rehabilitation. Dual allograft semitendinosus reconstruction is a new clinical alternative that has the theoretical advantages of a smaller incision, less dissection, and a stronger construct that may allow for faster rehabilitation.Questions/purposes: In a cadaver biomechanical model, we compared the dual allograft semitendinosus reconstruction with the myofascial turndown in terms of (1) mechanical strength and resistance to deformation and (2) failure mechanisms in reconstruction of large segmental Achilles defects.Methods: An 8-cm segmental Achilles defect was created in 18 cadaveric lower extremities, nine matched pairs without defect or previous surgery (mean age, 78.4 years; range, 60-97 years; three female and six male pairs). Femoral neck densitometry to determine bone mineral density found that all specimens except two were osteopenic or osteoporotic. Specimens in each pair were assigned to allograft or turndown reconstruction. The constructs were mounted on a load frame and differential variable reluctance transducers were applied to measure deformation. Specimens were preconditioned and then loaded axially. Tensile force and proximal and distal construct deformation were measured at clinical failure, defined as 10 mm of displacement, and at ultimate failure, defined as failure of the reconstruction. Failure mechanism was recorded.Results: Tensile strength at time zero was higher in the allograft versus the turndown construct at clinical failure (156.9 ± 29.7 N versus 107.2 ± 20.0 N, respectively; mean difference, -49.7 N; 95% CI, -66.3 to -33.0 N; p < 0.001) and at ultimate failure (290.9 ± 83.2 N versus 140.7 ± 43.5 N, respectively; mean difference, -150.2 N; 95% CI, -202.9 to -97.6 N; p < 0.001). Distal construct deformation was lower in the turndown versus the allograft construct at clinical failure (1.6 ± 1.0 mm versus 4.7 ± 0.7 mm medially and 2.2 ± 1.0 mm versus 4.8 ± 1.1 mm laterally; p < 0.001). Semitendinosus allograft failure occurred via calcaneal bone bridge fracture in eight of nine specimens. All myofascial turndowns failed via suture pullout through the fascial tissue at its insertion.Conclusion: In this comparative biomechanical study, dual semitendinosus allograft reconstruction showed greater tensile strength and construct deformation compared with myofascial turndown in a cadaveric model of large Achilles tendon defects.Clinical Relevance: Further study of dual semitendinosus allograft for treatment of severe Achilles tendon defects with cyclic loading and investigation of clinical results will better elucidate the clinical utility and indications for this technique. [ABSTRACT FROM AUTHOR]

Background: There is some evidence that functional performance and validated outcome scores differ according to the gender, age, and sport participation status of a patient after anterior cruciate ligament (ACL) reconstruction. However, the impact of these three factors, and interaction among them, has not been studied across a large relatively homogeneous group of patients to better elucidate their impact.Questions/purposes: We reviewed a large cohort of patients who had undergone ACL reconstruction to determine if ROM, knee laxity, objective performance measures, and validated outcome scores differed according to (1) gender; (2) age; and (3) sport participation status.Methods: This was a retrospective analysis of prospectively collected data. Between 2007 and 2016, we performed 3452 single-bundle ACL reconstructions in patients who participated in sport before ACL injury. Of those, complete followup (including preoperative scores and scores at 1 year after surgery; mean, 14 months; range, 12-20 months) was available on 2672 (77%) of patients. Those lost to followup and those accounted for were not different in terms of age, gender, and sports participation at baseline. The study group consisted of 1726 (65%) men and 946 (35%) women with a mean ± SD age of 28 ± 10 years. For these patients, the following measures were obtained: knee ROM (flexion and extension deficit), instrumented knee laxity, single and triple hop for distance limb symmetry index (LSI), International Knee Documentation Committee (IKDC) subjective evaluation, and Single Assessment Numeric Evaluation score. Mean scores and measures of variability were calculated for each outcome measure. Comparisons were made among gender, age, and sport status.Results: Men had less knee laxity after reconstruction (men 1.1 ± 2.2 mm, women 1.3 ± 2.4 mm; mean difference 0.2 mm [0.1-0.4], p < 0.001), greater limb symmetry (single limb hop men: 94% ± 12%, women 91% ± 13%, mean difference 3% [2%-4%], p < 0.001), and higher IKDC scores than did women (men 84 ± 12, women 82 ± 12, mean difference 2 [1-3], p < 0.001). With the exception of instrumented laxity, all outcome measures showed reduced deficits and higher scores in younger patients. This was most marked for LSI scores between the youngest and oldest aged patient groups (crossover hop: < 16 years 99% ± 10%, > 45 years 90% ± 16%, mean difference: 9 [5-11], p < 0.001). Patients who had returned to their preinjury sport also scored higher and had smaller deficits for all outcomes except ROM compared with patients who had not returned to sport at the time of followup (IKDC subjective: returned 90 ± 9, no sport 79 ± 12, mean difference 11 points [9-12], p < 0.001; single limb hop: returned 97 ± 10, no sport 91 ± 14, mean difference 6% [5%-7%], p < 0.001).Conclusions: This study showed that some of the most commonly used functional performance and validated clinical scores for ACL reconstruction are superior for patients who are younger, male, and have returned to preinjury sport. Reference to these data allows clinicians to more effectively evaluate a patient based on their age, gender, and sport status when making return to sport and rehabilitation decisions.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: There are several options for reconstruction of proximal humerus resections after wide resection for malignant tumors in children. The clavicula pro humero technique is a biologic option that has been used in the past, but there are only scant case reports and small series that comment on the results of the procedure. Because the longevity of children mandates a reconstruction with potential longevity not likely to be achieved by other techniques, the clavicula pro humero technique may be a potential option in selected patients.Questions/purposes: (1) How successful is the clavicula pro humero procedure in achieving local tumor control? (2) What is the frequency of nonunion? (3) What are the complications of the procedure? (4) What scores do patients achieve (on the Musculoskeletal Tumor Society (MSTS) and the Toronto Extremity Salvage Score (TESS) after this procedure?Methods: Four university hospitals performed the clavicula pro humero technique in eight children aged 8 to 18 years between June 2006 and February 2014. During that period, general indications for this approach included all reconstructions of the proximal humerus for malignant tumors in children older than 8 years. All patients were followed for a mean of 40 months (range, 25-86 months); one patient was lost to followup before 2 years. The tumor resections removed the rotator cuff muscles in all patients, glenohumeral joint in five, and deltoid muscle in three. The median length of the bone defect after resection was 20 cm (range, 7-25 cm). It was reduced to 9 cm (range, 0-17 cm) or 27% (range, 0%-64%) of the total humerus length after clavicular rotation. Direct osteosynthesis (one patient), induced membrane technique (one patient), or vascularized fibular autograft (six patients) was used to complete the defect after rotation of the clavicle if necessary. Presence of union (defined as bone healing before 10 months, as assessed by disappearance of the osteotomy on AP and lateral view radiographs), and complications were determined by chart review performed by a surgeon not involved in patient care. Function assessed by the MSTS and the TESS scores were determined by the patients with their families.Results: None of the patients had tumor recurrence. One patient died of pulmonary metastases before the 2-year followup. Proximal and distal bone unions were achieved before 10 months without an additional surgical procedure in two and six of seven patients, respectively. Fourteen local complications occurred resulting in nine revision operations. The main complication was aseptic proximal pseudarthrosis (five patients); other complications included one proximal junction fracture, one clavicle fracture complicated by clavicle osteolysis, one distal junction fracture, one necrosis of the skin paddle of the fibular autograft, one glenoclavicular ossification, and one distal pseudarthrosis complicated by a fracture of this distal junction. Function, as assessed by the MSTS score, was a median of 23 of 30 (range, 11-27). The median TESS score was 82% (range, 75%-92%). Shoulder ROM (median; range) in abduction, front elevation, and external and internal rotations were 70°(30°-90°), 75°(30°-85°), 10°(0°-20°), and 80°(80°-100°), respectively. Three of the seven patients reported dissatisfaction with the cosmetic appearance.Conclusions: The clavicula pro humero technique achieved oncologic local control after resection and reconstruction of proximal humerus tumors in children. Although union times are approximately 2 years and some patients underwent augmentation with other grafts, it eventually provides a solid, painless, biologic, and stable reconstruction and creates a mobile acromioclavicular joint and generally good function. Nonunion of the proximal junction is the main complication of this technique. We cannot directly compare this technique with other reconstruction options, and longer followup is needed, but this may be a useful reconstruction option to consider in select pediatric patients with sarcomas of the proximal humerus.Level Of Evidence: Level IV, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Bone-patellar tendon-bone (bone-tendon-bone) and four-strand hamstring tendon grafts (hamstring) are the most commonly utilized autografts for primary anterior cruciate ligament (ACL) reconstruction. Existing clinical trials, registry studies, and meta-analyses offer conflicting opinions regarding the most favorable graft choice.Questions/purposes: Which graft type for ACL reconstruction (bone-tendon-bone or hamstring) has a higher risk of (1) graft rupture and/or (2) graft laxity?Methods: We performed a meta-analysis of randomized controlled trials (RCTs), prospective cohort studies, and high-quality national registry studies to compare the outcomes of primary ACL reconstruction with bone-tendon-bone autograft or hamstring autograft. Studies that compared these graft types were identified through a comprehensive search of electronic databases (PubMed, MEDLINE, EMBASE, and the Cochrane Library). Two independent reviewers utilized the Jadad scale for RCT study quality and the Modified Coleman Methodology Score for prospective comparative and registry study quality. The included studies were analyzed for the primary outcome measure of graft rupture with or without revision ACL surgery. In surviving grafts, secondary outcomes of graft laxity were quantified by KT1000/2000™ testing, a positive pivot shift test, and a positive Lachman test. Meta-analysis was performed with Review Manager. A total of 47,613 ACL reconstructions (39,768 bone-tendon-bone and 7845 hamstring) from 14 RCTs, 10 prospective comparative studies, and one high-quality national registry study were included in this meta-analysis. Mean age was 28 years in both groups. Sixty-three percent of patients in the bone-tendon-bone cohort were men versus 57% of patients in the hamstring cohort. Mean followup was 68 ± 55 months.Results: Two hundred twelve of 7560 (2.80%) bone-tendon-bone grafts ruptured compared with 1123 of 39,510 (2.84%) in the hamstring group (odds ratio = 0.83, 95% confidence interval, 0.72-0.96; p = 0.01). The number needed to treat analysis found that 235 patients would need to be treated with a bone-tendon-bone graft over a hamstring tendon graft to prevent one graft rupture. Instrumented laxity analysis showed that 22% (318 of 1433) of patients in the bone-tendon-bone group had laxity compared with 18% (869 of 4783) in the hamstring tendon group (odds ratio = 0.86; p = 0.16). Pivot shift analysis showed a positive pivot shift in 19% (291 of 1508) of the bone-tendon-bone group compared with 17% (844 of 5062) in the hamstring group (odds ratio = 0.89; p = 0.51). Lachman testing showed a positive Lachman in 25% (71 of 280) of patients receiving bone-tendon-bone grafts compared with 25% (73 of 288) in the hamstring group (odds ratio = 0.96; p = 0.84).Conclusions: In this meta-analysis of short- to mid-term followup after primary ACL reconstruction, hamstring autografts failed at a higher rate than bone-tendon-bone autografts. However, failure rates were low in each group, the difference observed was small, and we observed few differences between graft types in terms of laxity. Both graft types remain viable options for primary ACL reconstruction, and the difference in failure rate should be one part of a larger conversation with each individual patient about graft selection that should also include potential differences in donor site morbidity, complication rates, and patient-reported outcome measures. Continued prospective collection of patient data will be important going forward as we attempt to further characterize the potential differences in outcomes attributable to graft selection.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: The Taylor Spatial Frame™ (TSF) is a versatile variant of the traditional Ilizarov circular fixator. Although in widespread use, little comparative data exist to quantify the biomechanical effect of substituting the tried-and-tested Ilizarov construct for the TSF hexapod system.Questions/purposes: This study was designed to investigate the mechanical properties of the TSF system under physiologic loads, with and without the addition of a simulated bone model, with comparison to the standard Ilizarov frame.Methods: The mechanical behaviors of three identical four-ring TSF and Ilizarov constructs were tested under levels of axial compression, bending, and rotational torque to simulate loading during normal gait. An acrylic-pipe fracture model subsequently was mounted, using fine wires and 5 mm half pins, and the testing was repeated. Load-deformation curves, and so rigidity, for each construct were calculated, with statistical comparisons performed using paired t-tests.Results: Under axial loading, the TSF was found to be less rigid than the Ilizarov frame (645 ± 57 N/mm versus 1269 ± 256 N/mm; mean difference, 623 N/mm; 95% CI, 438.3-808.5 N/mm; p < 0.001), but more rigid under bending and torsional loads (bending: 42 ± 9 Nm/degree versus 78 ± 13 Nm/degree; mean difference, 37 Nm/degree; 95% CI, 25.0-47.9 Nm/degree; p < 0.001; torsion: 16 ± 2 Nm/degree versus 5 ± 0.35 Nm/degree; mean difference, 11 Nm/degree; 95% CI, 9.5-12.2 Nm/degree; p < 0.001). On mounting the bone models, these relationships broadly remained in the half-pin and fine-wire groups, however the half-pin constructs were universally more rigid than those using fine wires. This effect resulted in the TSF, using half pins, showing no difference in axial rigidity to the fine-wire Ilizarov (107 ± 3 N/mm versus 107 ± 4 N/mm; mean difference, 0.05 N/mm; 95% CI, -6.99 to 7.1 N/mm; p > 0.999), while retaining greater bending and torsional rigidity. Throughout testing, a small amount of laxity was observed in the TSF construct on either side of neutral loading, amounting to 0.72 mm (±0.37 mm) for a change in loading between -10 N and 10 N axial load, and which persisted with the addition of the synthetic fracture model.Conclusions: This study broadly shows the TSF construct to generate lower axial rigidity, but greater bending and torsional rigidity, when compared with the Ilizarov frame, under physiologic loads. The anecdotally described laxity in the TSF hexapod strut system was shown in vitro, but only at low levels of loading around neutral. It also was shown that the increased stiffness generated by use of half pins produced a TSF construct replicating the axial rigidity of a fine-wire Ilizarov frame, for which much evidence of good clinical and radiologic outcomes exist, while providing greater rigidity and so improved resistance to potentially detrimental bending and rotational shear loads.Clinical Relevance: If replicated in the clinical setting, these findings suggest that when using the TSF, care should be taken to minimize the observed laxity around neutral with appropriate preloading of the construct, but that its use may produce constructs better able to resist bending and torsional loading, although with lower axial rigidity. Use of half pins in a TSF construct however may replicate the axial mechanical behavior of an Ilizarov construct, which is thought to be conducive to bone healing. [ABSTRACT FROM AUTHOR]

Background: The modified Dunn procedure facilitates femoral capital realignment for slipped capital femoral epiphysis (SCFE) through a surgical hip dislocation approach. Iatrogenic postoperative hip instability after this procedure has not been studied previously; however, we were concerned when we observed several instances of this serious complication, and we wished to study it further.Questions/purposes: The purpose of this study was to evaluate the frequency, timing, and clinical presentation (including complications) associated with iatrogenic instability after the modified Dunn procedure for SCFE.Methods: Between 2007 and 2014, eight international institutions performed the modified Dunn procedure through a surgical dislocation approach in 406 patients. During the period in question, indications varied at those sites, but the procedure was used only in a minority of their patients treated surgically for SCFE (31% [406 of 1331]) with the majority treated with in situ fixation. It generally was performed for patients with severe deformity with a slip angle greater than 40°. Institutional databases were searched for all patients with SCFE who developed postoperative hip instability defined as hip subluxation or dislocation of the involved hip during the postoperative period. We reviewed in detail the clinical notes and operative records of those who presented with instability. We obtained demographic information, time from slip to surgery, type of fixation, operative details, and clinical course including the incidence of complications. Followup on those patients with instability was at a mean of 2 years (range, 1-5 years) after the index procedure. Complications were graded according to the modified Dindo-Clavien classification. Radiographic images were reviewed to measure the preoperative slip angle and the presence of osteonecrosis.Results: A total of 4% of patients treated with the modified Dunn procedure developed postoperative hip instability (17 of 406). Mean age of the patients was 13 years (range, 9-16 years). Instability presented as persistent hip pain in the postoperative period or was incidentally identified radiographically during the postoperative visit and occurred at a median of 3 weeks (range, 1 day to 2 months) after the modified Dunn procedure. Eight patients underwent revision surgery to address the postoperative instability. Fourteen of 17 patients developed femoral head avascular necrosis and three of 17 patients underwent THA during this short-term followup.Conclusions: Anterolateral hip instability after the modified Dunn procedure for severe, chronic SCFE is an uncommon yet potentially devastating complication. Future studies might evaluate the effectiveness of maintaining anterior hip precautions for several weeks postoperatively in an abduction brace or broomstick cast to prevent this complication.Level Of Evidence: Level IV, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Since the importance of an intact labrum for normal hip function has been shown, labral reattachment has become the standard method for open or arthroscopic treatment of hips with femoroacetabular impingement (FAI). However, no long-term clinical results exist evaluating the effect of labral reattachment. A 2-year followup comparing open surgical treatment of FAI with labral resection versus reattachment was previously performed at our clinic. The goal of this study was to report a concise followup of these patients at a minimum of 10 years.Questions/purposes: We asked if patients undergoing surgical hip dislocation for the treatment of mixed-type FAI with labral reattachment compared with labral resection had (1) improved hip pain and function based on the Merle d'Aubigné-Postel score; and (2) improved survival at 10-year followup.Methods: Between June 1999 and July 2002, we performed surgical hip dislocation with femoral neck osteoplasty and acetabular rim trimming in 52 patients (60 hips) with mixed-type FAI. In the first 20 patients (25 hips) until June 2001, a torn labrum or a detached labrum in the area of acetabular rim resection was resected. In the next 32 patients (35 hips), reattachment of the labrum was performed. The same indications were used to perform both procedures during the periods in question. Of the 20 patients (25 hips) in the first group, 19 patients (95%) (24 hips [96%]) were available for clinical and/or radiographic followup at a minimum of 10 years (mean, 13 years; range, 12-14 years). Of the 32 patients (35 hips) in the second group, 29 patients (91%) (32 hips [91%]) were available for clinical and/or radiographic followup at a minimum of 10 years (mean, 12 years; range, 10-13 years). We used the anterior impingement test to assess pain. Function was assessed using the Merle d'Aubigné- Postel score and ROM. Survivorship calculation was performed using the method of Kaplan-Meier with failure defined as conversion to THA, progression of osteoarthritis (of one grade or more on the Tönnis score), and a Merle d'Aubigné-Postel score < 15.Results: At the 10-year followup, hip pain in hips with labral reattachment was slightly improved for the postoperative Merle d'Aubigné-Postel pain subscore (5.0 ± 1.0 [3-6] versus 3.9 ± 1.7 [0-6]; p = 0.017). No difference existed for the prevalence of hip pain assessed using the anterior impingement test with the numbers available (resection group 52% [11 of 21 hips] versus reattachment group 27% [eight of 30 hips]; odds ratio, 3.03; 95% confidence interval [CI], 0.93-9.83; p = 0.062). Function was slightly better in the reattachment group for the overall Merle d'Aubigné-Postel score (16.7 ± 1.5 [13-18] versus 15.3 ± 2.4 [9-18]; p = 0.028) and hip abduction (45° ± 13° [range, 30°-70°] versus 38° ± 8° [range, 25°-45°]; p = 0.001). Hips with labral reattachment showed a better survival rate at 10 years than did hips that underwent labral resection (78%; 95% CI, 64%-92% versus 46%, 95% CI, 26%-66%; p = 0.009) with the endpoints defined as conversion to THA, progression of osteoarthritis, and a Merle d'Aubigné-Postel score < 15. With isolated endpoints, survival at 10 years was increased for labral reattachment and the endpoint Merle d'Aubigné score < 15 (83%, 95% CI, 70%-97% versus 48%, 95% CI, 28%-69%; p = 0.009) but did not differ for progression of osteoarthritis (83%, 95% CI, 68%-97% versus 81%, 95% CI, 63%-98%; p = 0.957) or conversion to THA (94%, 95% CI, 86%-100% versus 87%, 95% CI, 74%-100%; p = 0.366).Conclusions: The current results suggest the importance of preserving the labrum and show that resection may put the hip at risk for early deterioration. At 10-year followup, hips with labral reattachment less frequently had a decreased Merle d'Aubigné score but no effect on progression of osteoarthritis or conversion to THA could be shown.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Acetabular retroversion can cause impaction-type femoroacetabular impingement leading to hip pain and osteoarthritis. It can be treated by anteverting periacetabular osteotomy (PAO) or acetabular rim trimming with refixation of the labrum. There is increasing evidence that acetabular retroversion is a rotational abnormality of the entire hemipelvis and not a focal overgrowth of the anterior acetabular wall, which favors an anteverting PAO. However, it is unknown if this larger procedure would be beneficial in terms of survivorship and Merle d'Aubigné scores in a midterm followup compared with rim trimming.Questions/purposes: We asked if anteverting PAO results in increased survivorship of the hip compared with rim trimming through a surgical hip dislocation in patients with symptomatic acetabular retroversion.Methods: We performed a retrospective, comparative study evaluating the midterm survivorship of two matched patient groups with symptomatic acetabular retroversion undergoing either anteverting PAO or acetabular rim trimming through a surgical hip dislocation. Acetabular retroversion was defined by a concomitantly present positive crossover, posterior wall, and ischial spine sign. A total of 279 hips underwent a surgical intervention for acetabular retroversion at our center between 1997 and 2012 (166 periacetabular osteotomies, 113 rim trimmings through surgical hip dislocation). A total of 99 patients (60%) were excluded from the PAO group and 56 patients (50%) from the rim trimming group because they had any of several prespecified conditions (eg, dysplasia or pediatric conditions 61 [37%] for the PAO group and two [2%] for the rim trimming group), matching (10 [6%]/10 [9%] hips), deficient records (10 [6%]/13 [12%] hips), or the patient declined or was lost to followup (18 [11%]/31 [27%] hips). This left 67 hips (57 patients) that underwent anteverting PAO and 57 hips (52 patients) that had acetabular rim trimming. The two groups did not differ in terms of age, sex, body mass index, preoperative ROM, preoperative Merle d'Aubigné-Postel score, radiographic morphology of the acetabulum (except total and anterior acetabular coverage), alpha angle, Tönnis grade of osteoarthritis, and labral and chondral lesions on the preoperative MRI. During the period in question, we generally performed PAO from 1997 to 2003. With the availability of surgical hip dislocation and labral refixation, we generally performed rim trimming from 2004 to 2010. With growing knowledge of the underlying pathomorphology, anteverting PAOs became more common again around 2007 to 2008. A minimum followup of 2 years was required for this study. Failures were included at any time. The median followup for the anteverting PAO group was 9.5 years (range, 2-17.4 years) and 6.8 years (range, 2.2-10.5 years) for the rim trimming group (p < 0.001). Kaplan-Meier survivorship analysis was performed using the following endpoints at 5 and 10 years: THA, radiographic progression of osteoarthritis by one Tönnis grade, and/or Merle d'Aubigné-Postel score < 15 points.Results: Although the 5-year survivorship of the two groups was not different with the numbers available (86% [95% confidence interval {CI}, 76%-94%] for anteverting PAO versus 86% [95% CI, 76%-96%] for acetabular rim trimming), we found increased survivorship at 10 years in hips undergoing anteverting PAO for acetabular retroversion (79% [95% CI, 68%-90%]) compared with acetabular rim trimming (23% [95% CI, 6%-40%]) at 10 years (p < 0.001). The drop in the survivorship curve for the acetabular rim trimming through surgical hip dislocation group started at Year 6. The main reason for failure was a decreased Merle d'Aubigné score.Conclusions: Anteverting PAO may be the more appropriate treatment for hips with substantial acetabular retroversion. This may be the result of reduction of an already smaller lunate surface of hips with acetabular retroversion through rim trimming. However, rim trimming may still benefit hips with acetabular retroversion in which only one or two of the three signs are positive. Future randomized studies should compare these treatments.Level Of Evidence: Level III, therapeutic study. [ABSTRACT FROM AUTHOR]

Background: Voluntary knuckle cracking is a common habit, with a reported prevalence of 25% to 45%. Habitual knuckle cracking also is a frequent source of questions for physicians, and the largest study to date reported an association with functional hand impairments.Questions/purposes: (1) When compared with subjects who are not habitual knuckle crackers, do habitual knuckle crackers have greater QuickDASH scores, swelling, weakness, joint laxity, or ROM? (2) In subjects who crack their knuckles, does cracking immediately increase ROM? (3) What are the characteristic sonographic findings in joints that crack?Methods: A prospective, institutional review board-approved study was performed on 400 metacarpophalangeal joints (MPJs) in 40 asymptomatic adult subjects. Of those, 30 subjects had a history of habitual knuckle cracking (defined as daily voluntary popping of MPJs). Clinical history provided by all subjects included a standardized QuickDASH questionnaire. Physical examination was performed by two orthopaedic surgeons (blinded to subjects' knuckle-cracking history and sonographic outcomes). The physical examination included evaluation for swelling, grip strength, and ROM before and after attempted knuckle cracking. Sonographic examination was conducted by one sonographer, with static and real-time cine images recorded before, during, and after MPJ distraction was performed by the subjects. Two musculoskeletal radiologists (blinded to subjects' knuckle-cracking history) interpreted the images for a definite hyperechoic focus during and after MPJ distraction; this was compared against the reference standard of an audible "crack" during joint distraction.Results: Comparing subjects with knuckle cracking with those who did not crack their knuckles, there was no differences in QuickDASH scores (knuckle crackers, 3.7 ± 5.2; nonknuckle crackers, 3.2 ± 6.3; mean difference, 0.6; 95% CI, -3.5 to 4.6; p = 0.786), laxity (knuckle crackers, 2.0 ± 1.8; nonknuckle crackers, 0.3 ± 0.7; mean difference, 1.7; 95% CI, 0.5-2.9; p = 0.191), and grip strength (preultrasound, right hand, p = 0.499, left hand p = 0.575; postultrasound, right hand p = 0.777, left hand p = 0.424); ROM comparisons between subjects with a history of habitual knuckle cracking versus subjects without such a history only yielded increased ROM in joints that cracked during manipulation (knuckle cracking, 143.8° ± 26.5°; nonknuckle cracking, 134.9° ± 28.6°; mean difference, 9.0°; 95% CI, 2.9°-15.1°; p = 0.004). Swelling was not observed in any subjects, including when comparing MPJs before versus after distraction maneuvers that resulted in audible cracks. Immediately after a documented crack, there were greater ranges of motion with active flexion (preultrasound, 85.7° ± 12.4°; postultrasound, 88.6° ± 11.6°; mean difference, -2.9°; 95% CI, -5.1° to -0.8°; p = 0.009), passive flexion (preultrasound, 96.1° ± 12.4°; postultrasound, 100.3° ± 10.4°; mean difference, -4.3°; 95% CI, -6.2° to -2.3°; p < 0.001), passive extension (preultrasound, 41.8° ± 18.1°; postultrasound, 45.2° ± 17.6°; mean difference, -3.5°; 95% CI, -6.9° to -0.1°; p = 0.046), and passive total ROM (preultrasound, 137.8° ± 24.8°; postultrasound, 145.6° ± 23.1°; mean difference, -7.7°; 95% CI, -11.7° to -3.8°; p < 0.001). The characteristic sonographic finding observed during cracking events is an echogenic focus that appears de novo dynamically in the joint during distraction.Conclusions: We found no evidence of immediate adverse physical examination findings after knuckle cracking. However, we did find a small increase in ROM among joints that cracked compared with those that did not. Future studies should examine if there are any long-term beneficial and adverse clinical outcomes associated with habitual knuckle cracking.Level Of Evidence: Level I, prognostic study. [ABSTRACT FROM AUTHOR]