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Femoroacetabular impingement (FAI) has a strong clinical association with the development of hip osteoarthritis (OA); however, the pathobiological mechanisms underlying the transition from focal impingement to global joint degeneration remain poorly understood. The purpose of this study is to use whole-genome RNA sequencing to identify and subsequently validate differentially expressed genes (DEGs) in femoral head articular cartilage samples from patients with FAI and hip OA secondary to FAI. Thirty-seven patients were included in the study with whole-genome RNA sequencing performed on 10 gender-matched patients in the FAI and OA cohorts and the remaining specimens were used for validation analyses. We identified a total of 3531 DEGs between the FAI and OA cohorts with multiple targets for genes implicated in canonical OA pathways. Quantitative reverse transcription-polymerase chain reaction validation confirmed increased expression of FGF18 and WNT16 in the FAI samples, while there was increased expression of MMP13 and ADAMTS4 in the OA samples. Expression levels of FGF18 and WNT16 were also higher in FAI samples with mild cartilage damage compared to FAI samples with severe cartilage damage or OA cartilage. Our study further expands the knowledge regarding distinct genetic reprogramming in the cartilage between FAI and hip OA patients. We independently validated the results of the sequencing analysis and found increased expression of anabolic markers in patients with FAI and minimal histologic cartilage damage, suggesting that anabolic signaling may be increased in early FAI with a transition to catabolic and inflammatory gene expression as FAI progresses towards more severe hip OA. Clinical significance:Cam-type FAI has a strong clinical association with hip OA; however, the cellular pathophysiology of disease progression remains poorly understood. Several previous studies have demonstrated increased expression of inflammatory markers in FAI cartilage samples, suggesting the involvement of these inflammatory pathways in the disease progression. Our study further expands the knowledge regarding distinct genetic reprogramming in the cartilage between FAI and hip OA patients. In addition to differences in inflammatory gene expression, we also identified differential expression in multiple pathways involved in hip OA progression.

IntroductionThe natural history of Femoroacetabular Impingement (FAI) has been clinically associated with the development of hip osteoarthritis (OA); however, the pathobiological mechanisms underlying the transition from focal impingement to global joint degeneration remain unclear. The goal of the study was to investigate differences in transcriptomic profiles of the cartilage from FAI and hip OA patients using whole-genome RNA sequencing.MethodsThirty-seven patients were included in the study with 20 diagnosed with FAI undergoing arthroscopic treatment and 15 diagnosed with hip OA undergoing total hip arthroplasty (THA). Cartilage samples were obtained intraoperatively over the femoral head-neck junction for both FAI and OA cohorts. Whole-genome RNA sequencing was performed on 10 gender-matched patients in the FAI and OA cohorts with the remaining samples used for histopathologic analysis using the Osteoarthritis Research Society International (OARSI) grading system and qRT-PCR validation. Target validation was further confirmed with immunohistochemical staining for FGF18 on FAI and OA cartilage samples.ResultsWe identified a total of 3,531 Differentially Expressed Genes (DEGs) between the FAI and OA cohorts with multiple targets for genes implicated in canonical OA pathways. qRT-PCR validation confirmed increased expression of FGF18 and WNT16 in the FAI samples, while there was increased expression of MMP13 and ADAMTS4 in the OA samples. Expression levels of FGF18 and WNT16 were also higher in FAI samples with mild cartilage damage (OARSI grades 1-2) compared to FAI samples with severe cartilage damage or OA cartilage (OARSI grade 4-6). Immunohistochemical evaluation identified increased FGF18 staining in OARSI grade 1-2 FAI samples compared to OARSI grade 5-6 FAI and OA samples.ConclusionsRNA sequencing of cartilage of FAI and hip OA patients identified a negative association of FGF18 expression levels with cartilage damage severity, suggesting that FGF18 may be used as a marker for hip OA progression. Future evaluation of FGF18 signaling as well as other markers in early OA may yield further insight into disease prevention and treatment.

The purpose of this study was to perform a cross-sectional analysis of diversity among academic shoulder and elbow surgeons in the United States.US shoulder and elbow surgeons who participated in shoulder and elbow fellowship and/or orthopedic surgery resident education as of November 2018 were included. Demographic data (age, gender, race), practice setting, years in practice, academic rank, and leadership roles were collected through publicly available databases and professional profiles. Descriptive statistics were performed and findings were compared between different racial and gender groups. Statistical significance was set at P.05.A total of 186 orthopedic shoulder and elbow surgeons were identified as participating in shoulder and elbow fellowship and/or orthopedic surgery residency education. Overall, 83.9% were white, 14.5% were Asian, 1.1% were Hispanic, 0.5% were an other race, and 0% were African American. In addition, 94.6% of surgeons were male, whereas 5.4% were female. Further, 64.5% of all surgeons had been in practice for10 years, and 39.2% worked in an urban setting. Less than half (40.3%) of the surgeons practicing primarily at academic institutions held a professor rank. White surgeons had a significantly greater time in practice vs. nonwhite surgeons (mean 18.8 vs. 12.6 years, P.01) and were more likely to hold a professor rank (44.0% vs. 21.7%, P = .04).Racial and gender diversity among US shoulder and elbow surgeons who participate in fellowship and residency education is lacking. Hispanic, African American, and female surgeons are underrepresented. Efforts should be made to identify the reasons for these deficiencies and address them to further advance the field of orthopedic shoulder and elbow surgery.

Background: Orthopaedic surgery is ever changing and depends on diverse technical and intellectual skill sets. The purpose of the current study was to evaluate the percentage of academic orthopaedic surgeons with additional graduate degrees in the United States. Methods: Data including advanced degree(s) (eg, PhD, MS, MBA, MPH, JD, and DVM), academic rank, leadership position, subspecialty, years since training completion, and sex were collected from websites for all academic orthopaedic surgery departments in the United States. Univariate analyses were performed to evaluate for differences in demographic data based on the advanced degree status. Data from the National Resident Matching Program (NRMP) were used to characterize graduate degree-holding US senior medical students who ranked orthopaedic surgery first relative to peers without additional advanced degrees and to applicants who ranked other specialties first. Results: Of 4,519 faculty at 175 academic orthopaedic surgery departments in the United States, 7.1% held a graduate degree in addition to a medical doctorate. There was no difference in the percentage of faculty who held departmental leadership positions (P = 0.62) or who were full professors (P = 0.66) based on holding an additional graduate degree. Of 678 US senior applicants who ranked orthopaedic surgery first and successfully matched into the specialty in 2018, 12.5% held an additional graduate degree and 1.3% were MD-PhDs. Orthopaedic surgery had the second lowest percentage of matched medical students with additional advanced degrees, which was significantly lower than the top 10 specialties (range 16.1% to 21.6%; P < 0.05). Orthopaedic surgery recruited 1.6% of all MD-PhD applicants in 2018. Discussion: Few academic orthopaedic surgery faculty and admitted orthopaedic residency candidates have additional graduate school training. The low percentage of orthopaedic faculty and trainees with additional advanced degrees relative to other specialties may represent a missed opportunity to recruit individuals with diverse skills to advance the field of orthopaedic surgery.

The purpose of this study was to compare the cross-sectional area (CSA) of joint visualization between extended interportal and T-capsulotomies. Twenty fresh-frozen cadaveric hips were dissected to their capsuloligamentous complexes and fixed in a custom apparatus in neutral hip position. Ten hips underwent sequential interportal capsulotomies at lengths of 2, 4, 6, and 8 cm. Ten hips underwent sequential T-capsulotomies starting from a 4 cm interportal capsulotomy, creating a 2 cm T-capsulotomy (Half-T), and finally a 4 cm T-capsulotomy (Full-T). Following each sequential capsule change in both groups, a high-resolution digital photograph was taken to measure the visualized intra-articular cross-sectional area (CSA). Independent t-test was used to compare CSA interportal and T-capsulotomy groups. Analysis demonstrated a statistically significant increase in CSA visualization with each sequential increase in interportal capsulotomy length up to 6 cm (2cm: 0.6 ± 0.2 cm2; 4cm: 2.1 ± 0.5 cm2 (p

Background: Threshold values for patient-reported outcome measures, such as the minimum clinically important difference (MCID) and patient acceptable symptomatic state (PASS), are important for relating postoperative outcomes to meaningful functional improvement. Purpose: To determine the PASS and MCID after hip arthroscopy for femoroacetabular impingement using the Patient-Reported Outcomes Measurement Information System (PROMIS) questionnaire. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A consecutive series of patients undergoing primary hip arthroscopy for femoroacetabular impingement were administered preoperative and minimum 1-year postoperative PROMIS surveys focusing on physical function (PF) and pain interference (PI). External anchor questions for the MCID and PASS were given with the postoperative PROMIS survey. Receiver operator curves were constructed to determine the threshold values for the MCID and PASS. Curves were generated for the study population as well as separate cohorts segregated by median baseline PF or PI scores and preoperative athletic participation. A multivariate post hoc analysis was then constructed to evaluate factors associated with achieving the PASS or MCID. Results: There were 113 patients (35% male; mean ± SD age, 32.8 ± 12.5 years; body mass index, 25.8 ± 4.8 kg/m2), with 60 (53%) reporting preoperative athletic participation. Survey time averaged 77.5 ± 49.2 seconds. Anchor-based MCID values were 5.1 and 10.9 for the PF and PI domains, respectively. PASS thresholds were 51.8 and 51.9 for the PF and PI, respectively. PASS values were not affected by baseline scores, but athletic patients had a higher PASS threshold than did those not participating in a sport (53.1 vs 44.7). MCID values were affected by preoperative baseline scores but were largely independent of sports participation. A post hoc analysis found that 94 (83%) patients attained the MCID PF while 66 (58%) attained the PASS PF. A multivariate nominal logistic regression found that younger patients ( P = .01) and athletic patients ( P = .003) were more likely to attain the PASS. Conclusion: The PROMIS survey is an efficient metric to evaluate preoperative disability and postoperative function after primary hip arthroscopy for femoroacetabular impingement. The MCID and PASS provide surgeons with threshold values to help determine PROMIS scores that are clinically meaningful to patients, and they can assist with therapeutic decision making as well as expectation setting.

Objectives: The morphological deformities in Femoroacetabular Impingement (FAI) have been associated with hip osteoarthritis (OA), however the molecular mechanisms for OA initiation and progression are poorly understood. The purpose of this study was to use whole genome RNA sequencing to characterize differences in gene expression articular cartilage samples isolated from patients undergoing surgery for FAI and idiopathic OA. We hypothesized that there would be significant differences in genes expression in pathways related to inflammation as well as cartilage and bone turnover. Methods: 20 patients undergoing either hip arthroscopy for FAI (5 male, 5 female) or total hip arthroplasty (5 male, 5 female) for end-stage osteoarthritis were included in the study. FAI patients required a Cam deformity with an Alpha Angle greater than 55 while patients with dysplasia (LCEA

Patients with bilateral femoroacetabular impingement syndrome treated with either staged or simultaneous hip arthroscopy have similar postoperative outcomes compared with patients undergoing unilateral procedures. A longer duration between surgeries is associated with inferior outcomes; however, the reasons underlying this trend are unclear. Identifying prognostic variables that are associated with contralateral symptom onset and disease progression are important goals for future investigation.

Background: Interportal and T-capsulotomies are popular techniques for exposing femoroacetabular impingement deformities. The difference between techniques with regard to the force required to distract the hip is currently unknown. Purpose: To quantify how increasing interportal capsulotomy size, conversion to T-capsulotomy, and subsequent repair affect the force required to distract the hip. Study Design: Controlled laboratory study. Methods: Eight fresh-frozen cadaveric hip specimens were dissected and fixed in a materials testing system, such that pure axial distraction of the iliofemoral ligament could be achieved. The primary outcome measure was the load required to distract the hip to a distance of 6 mm at a rate of 0.5 mm/s. Each hip was tested in the intact state and then sequentially under varying capsulotomy conditions: 2-cm interportal, 4-cm interportal, half-T (4-cm interportal and 2-cm T-capsulotomy), and full-T (4-cm interportal and 4-cm T-capsulotomy). After serial testing, isolated T-limb repair and then subsequent complete repair were performed. Repaired specimens underwent distraction testing as previously stated to assess the ability to restore hip stability to the native profile. Distraction force as well as the relative distraction force (percentage normalized to the intact capsule) were compared between all capsulotomy and repair conditions. Results: Increasing interportal capsulotomy size from 2 to 4 cm resulted in significantly less force required to distract the hip ( P < .001). The largest relative decrease in force was seen between the intact state (274.6 ± 71.2 N; 100%) and 2-cm interportal (209.7 ± 73.2 N; 76.4% ± 15.6%; P = .0008). There was no significant mean difference in distraction force when 4-cm interportal (160.4 ± 79.8 N) was converted to half-T (140.7 ± 73.5 N; P = .270) and then full-T (112.0 ± 70.2 N; P = .204). When compared with the intact state, isolated T-limb repair partially restored stability (177.3 ± 86.3 N; 63.5% ± 19.8%; P < .0001), while complete repair exceeded native values (331.7 ± 103.7 N; 122.7% ± 15.1%; P = .0008). Conclusion: The conversion of interportal capsulotomy to T-capsulotomy did not significantly affect the force required to distract the hip in a cadaveric model. However, larger interportal capsulotomies resulted in significant stepwise decreases in distraction force. When performing interportal or T-capsulotomy, the iliofemoral ligament strength is significantly decreased, but complete capsular repair demonstrated the ability to restore joint stability to the native, intact hip. Clinical Relevance: Increasing interportal capsulotomy size decreases the force required to distract the hip. In an effort to maximize visualization and minimize the magnitude of iliofemoral ligament fibers cut, many surgeons have moved from extended interportal capsulotomy to T-capsulotomy. Interportal and T-capsulotomies result in equivalent hip distraction, partial capsular repair marginally improves hip stability, and only complete repair has the ability to restore the hip to its native biomechanical profile.

Background: Hip arthroscopy in the setting of dysplasia and borderline dysplasia is controversial. Dysplasia severity is most often defined by the lateral center edge angle (LCEA) but can also be evaluated radiographically by the acetabular inclination (AI). Purpose/Hypothesis: The purpose was to determine the effect of AI on outcomes after isolated hip arthroscopy for femoroacetabular impingement (FAI). We hypothesized that patients with dysplasia would have higher rates of arthroplasty as well as inferior clinical and functional outcomes compared with patients who did not have dysplasia. Study Design: Cohort study; Level of evidence, 3. Methods: A hip arthroscopy registry was reviewed for participants undergoing arthroscopic correction of FAI from February 28, 2008, to June 10, 2013. Participants required a clinical diagnosis and isolated arthroscopic correction of FAI with preoperative imaging and intraoperative cartilage status recorded. AI dysplasia was defined as an AI greater than 10°, LCEA dysplasia as LCEA less than 18°, and borderline LCEA dysplasia as LCEA 18° to 25°. Patients without an acetabular deformity (LCEA 25°-40°; AI Results: This study included 419 patients: 9 (2%) with LCEA dysplasia, 42 (10%) with AI dysplasia, and 51 (12%) with borderline dysplasia. The AI but not LCEA was significantly correlated with lower outcome scores on the modified Harris Hip Score ( r = 0.13; P = .01), Non-Arthritic Hip Score ( r = 0.10; P = .04), and Hip Outcome Score–Sports Subscale ( r = 0.11; P = .04). A total of 58 patients (14%) underwent arthroplasty at 31 ± 20 months postoperatively. Patients with LCEA dysplasia had an arthroplasty rate of 56% (odds ratio, 8.4), whereas patients with AI dysplasia had an arthroplasty rate of 31% (odds ratio, 3.3), which was significantly greater than the rate for the nondysplastic cohort (13.5%; P < .0001). Patients with borderline LCEA dysplasia did not have increased rates of arthroplasty. A multivariate analysis found increasing age, increasing AI, Tönnis grade higher than 1, and femoral Outerbridge grade higher than 2 to be most predictive of conversion to arthroplasty. Conclusion: We found that an elevated AI, along with increasing age, Tönnis grade, and femoral Outerbridge grade significantly predict early conversion to arthroplasty after isolated hip arthroscopy. We recommend using the AI, in addition to the LCEA, in evaluating hip dysplasia before hip arthroscopy.

Background: There has been increasing interest in defining clinically meaningful outcomes in patient reported outcomes following orthopaedic surgery. Little is known about the factors associated with clinically meaningful outcomes after hip arthroscopy for femoroacetabular impingement. Study Design: Case-control study; Level of evidence, 3. Purpose: To report on a large, prospectively collected consecutive series of patients who underwent comprehensive arthroscopic treatment of femoroacetabular impingement (FAI) and capsular management with greater than 2-year follow-up. The objectives were to determine (1) what percentage of patients achieve clinically significant outcomes after hip arthroscopic surgery for FAI as determined by the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) and (2) what factors are associated with achieving the MCID and PASS. Methods: Data from an institutional repository of consecutive patients undergoing primary hip arthroscopic surgery with routine capsular closure for FAI that had failed nonsurgical management between January 2012 and January 2014 were prospectively collected and analyzed. Of 474 patients during the enrollment period, 386 (81.4%) patients were available for a minimum 2-year follow-up. Demographics, radiographic measurements, intraoperative characteristics, and patient-reported outcome scores were collected. The primary outcome measure was achieving published thresholds for the MCID and PASS for the Hip Outcome Score (HOS)–Activities of Daily Living (ADL) in patients with FAI. The HOS–Sport-Specific Subscale (SSS), complications, and reoperations were secondary outcome measures. Multivariate regression analyses were conducted to identify factors associated with achieving the MCID and PASS. Results: At a minimum of 2-year follow-up, the patients had statistically significant improvements in all patient-reported outcomes (HOS-ADL, HOS-SSS, and modified Harris Hip Score [mHHS]; P < .001 for all), with a 1.2% rate of revision hip arthroscopic surgery and 1.7% rate of conversion to total hip arthroplasty. The MCID was achieved by 78.8% of patients for the HOS-ADL, and the PASS was achieved by 62.5% for the HOS-ADL. Younger age ( P = .008), Tönnis grade 0 ( P = .022), and lower preoperative HOS-ADL score ( P < .001) were associated with successfully achieving the MCID for the HOS-ADL. Younger age ( P < .001), larger medial joint space width ( P = .028), and higher preoperative HOS-ADL score ( P < .001) were associated with achieving the PASS for the HOS-ADL. Younger age ( P < .001), lower body mass index ( P = .006), non–workers’ compensation status ( P = .020), and lower preoperative HOS-SSS score ( P < .001) were associated with achieving the MCID for the HOS-SSS. Younger age ( P = .001), Tönnis grade 0 ( P = .014), running ( P = .008), and higher preoperative HOS-SSS score ( P < .001) were associated with achieving the PASS for the HOS-SSS. Overall, 49.4% of patients achieved all 4 clinically significant outcomes: both the MCID and PASS for the HOS-ADL and HOS-SSS. Conclusion: The majority of patients undergoing hip arthroscopic surgery with routine capsular closure for FAI experienced clinically significant outcomes that met the MCID or PASS criteria, with low rates of revision and conversion to total hip arthroplasty. Factors associated with these successful outcomes on multivariate analyses included younger age with a normal joint space. Patients with lower preoperative HOS scores were more likely to achieve the MCID, whereas patients with higher preoperative HOS scores were more likely to achieve the PASS.

Background: The literature contains conflicting reports regarding whether outcomes of hip arthroscopic surgery for patients with borderline dysplasia are inferior to outcomes in patients with normal acetabular coverage. Purpose: To assess differences in the outcomes of hip arthroscopic surgery for femoroacetabular impingement (FAI) in groups of patients with borderline dysplasia and normal coverage. Study Design: Cohort study; Level of evidence, 3. Methods: A registry of consecutive patients who had undergone primary hip arthroscopic surgery with capsular plication for FAI between January 2012 and January 2014 were divided based on the preoperative lateral center-edge angle (LCEA) into 2 distinct groups: (1) borderline dysplasia (LCEA 18°-25°) and (2) normal acetabular coverage (LCEA 25.1°-40°). There were 36 patients in the borderline dysplastic group and 312 patients in the normal coverage group. The primary outcome measure was the Hip Outcome Score–Activities of Daily Living (HOS-ADL) at a minimum of 2 years postoperatively. Secondary outcome measures included the HOS-Sports and modified Harris Hip Score (mHHS). Results: The mean preoperative LCEA differed significantly between groups (23.4° ± 1.5° for borderline dysplastic, 32.5° ± 3.8° for normal coverage; P < .001). The borderline dysplastic group had a higher percentage of female patients than the normal coverage group (27/36 [75%] vs 177/312 [57%], respectively; P = .048). There were no differences in other preoperative demographics and radiographic parameters. At a minimum 2 years after hip arthroscopic surgery (mean follow-up, 2.6 ± 0.6 years), both groups demonstrated significant improvements in all patient-reported outcome scores ( P < .001 in all cases). There were no significant differences between the borderline dysplastic and normal coverage groups in final outcome scores, score improvements, or percentage of patients experiencing clinically significant improvements. One patient in the borderline dysplastic group (3%) underwent revision hip arthroscopic surgery, and none underwent total hip arthroplasty during the follow-up period. There were no differences between the borderline dysplastic and normal coverage groups with regard to subsequent surgery. Female patients in the borderline dysplastic group had greater improvements in the mean HOS-ADL (25.9 ± 16.3 vs 10.8 ± 18.5, respectively; P = .05) and mHHS (27.9 ± 12.9 vs 8.1 ± 19.0, respectively; P = .005) compared with male patients in the borderline dysplastic group, but male and female patients did not differ in outcomes for the normal coverage group. Conclusion: Patients who underwent hip arthroscopic surgery for FAI with capsular plication experienced significant clinical improvements with low rates of subsequent surgery, regardless of whether their acetabulum had borderline dysplasia or normal coverage.

Background: Femoroacetabular impingement (FAI) most commonly manifests as anterior groin pain. Patients occasionally have posterior pain but otherwise have clinical and radiographic evidence of FAI. Purpose: To compare outcomes of hip arthroscopy for FAI in patients with atypical posterior pain versus a matched group with the typical anterior pain presentation. Study Design: Cohort study; Level of evidence, 3. Methods: Patients undergoing primary hip arthroscopy for FAI were identified from a clinical repository between January 2012 and 2014. Of 503 patients during the study period, 31 (6.2%) had posterior hip or buttock pain reproduced with flexion, adduction, and internal rotation (FADDIR) and were classified as “atypical,” while those with anterior hip or groin pain were classified as “typical.” Atypical patients were matched in a 1:2 cohort to the typical group based on sex, age, and body mass index (BMI). Postoperative patient-reported outcomes included visual analog scale (VAS) for pain, modified Harris Hip Score (mHHS), and Hip Outcome Scores with Activities of Daily Living (HOS-ADL) and Sports-Specific (HOS-SS) subscales. Results: Of the 31 atypical patients, 28 (90.3%) were available for a minimum 2-year follow-up (mean ± SD, 2.6 ± 0.6 years). These patients were matched with 56 typical patients. No differences were noted between typical and atypical cohorts in preoperative demographic or radiographic parameters. Postoperatively, both groups demonstrated significant improvements in mHHS (atypical 60.1 ± 12.4 to 78.8 ± 12.9; typical 60.0 ± 12.3 to 76.9 ± 13.6; P < .001), HOS-ADL (atypical 68.5 ± 17.0 to 88.6 ± 11.0; typical 69.2 ± 17.1 to 86.8 ± 14.7; P < .001), and HOS-SS (atypical 42.0 ± 25.5 to 71.0 ± 26.2; typical 44.4 ± 24.9 to 71.3 ± 27.3; P < .001). No differences were found in 2-year score improvements between the atypical and typical cohorts (mHHS 18.7 ± 13.4 vs 16.9 ± 13.1, P = .48; HOS-ADL 20.1 ± 16.8 vs 17.6 ± 14.6, P = .19; HOS-SS 29.0 ± 30.2 vs 26.9 ± 27.3, P = .93). Also, no significant differences were found in VAS pain improvement (5.0 ± 3.2 vs 5.6 ± 2.8, P = .56) or postoperative satisfaction (79.5 ± 5.5 vs 77.5 ± 4.1, P = .78). Conclusion: Atypical posterior hip pain is an uncommon presentation of FAI. Patients demonstrate similar significant improvements after hip arthroscopy in outcome scores, postoperative pain, and satisfaction compared with patients who have classic anterior groin pain.

Purpose The purpose of this study was to examine the hip capsule in a subset of symptomatic patients who underwent capsular closure during hip arthroscopy. Methods All patients undergoing primary hip arthroscopy for femoroacetabular impingement (FAI) with routine capsular closure between January 1, 2012, and December 31, 2015, were eligible. Only patients with unilateral surgery and a postoperative magnetic resonance imaging (MRI; ordered for persistent symptoms) were included. Four independent reviewers evaluated each hip capsule for thickness and the absence or presence of defects. Results During the study, 1,463 patients had hip arthroscopy for FAI with routine capsular closure, and 53 (3.6%) underwent a postoperative MRI. Fourteen of the 53 were excluded owing to revision status or additional procedures. The final study population included 39 patients (23 female patients and 16 male patients), with an average patient age of 31.7 ± 11.4 years and an average body mass index of 23.3 ± 2.9. There were 3 (7.5%) capsular defects, and the intraclass correlation coefficient (ICC) was 0.82. The operative hip capsule was significantly thicker in the zone of capsulotomy, and subsequent repair as compared with the unaffected, contralateral hip capsule (5.0 ± 1.2 mm vs 4.6 ± 1.4 mm; P = .02), ICC 0.83. Additionally, males had thicker hip capsules as compared with their female counterparts, on the operative side (5.4 ± 1.1 mm vs 4.5 ± 1.2 mm; P = .02) and the nonoperative side (4.8 ± 1.6 mm vs 4.1 ± 0.9 mm; P = .08). Conclusions In a subset of symptomatic patients after hip arthroscopy for FAI, the majority (92.5%) of the repaired hip capsules remained closed at greater than 1 year of follow-up. The hip capsule adjacent to the capsulotomy and subsequent repair is thickened compared with the same location on the contralateral, nonoperative hip. Aside from gender, patient-related and FAI-related factors do not correlate with capsular thickness nor do they seem to correlate with the propensity to develop a capsular defect. Level of Evidence Level IV, prognostic case series.

A systematic approach to interpretation of magnetic resonance imaging of the hip and pelvis can facilitate identifying imaging findings that correlate with the clinical history and physical examination.This systematic approach flows outside-to-inside. Images with a large field of view are used for i

Background: Femoroacetabular impingement (FAI) is most commonly diagnosed in athletes who sustain repetitive flexion loading to their hips. No studies to date have focused solely on patients’ return-to-running ability after hip arthroscopy. Purpose: To evaluate patients’ ability to return to running after hip arthroscopy for FAI and capsular plication. Study Design: Case series; Level of evidence, 4. Methods: Clinical data were retrospectively retrieved for 51 consecutive patients with FAI (22 men, 29 women) who had undergone hip arthroscopy for the treatment of FAI and identified themselves as recreational or competitive runners on intake forms. Two-year outcome measures included the modified Harris Hip Score (mHHS) and the Hip Outcome Score Activities of Daily Living (HOS-ADL) and Sport-Specific (HOS-SS) subscales. A postoperative return-to-running survey was used to obtain running-specific information. Results: Patient age and body mass index (BMI) were a mean (±SD) of 26.3 ± 7.8 years and 23.7 ± 3.3 kg/m2, respectively. Before surgery, patients had refrained from running because of pain for a mean of 8.1 ± 5.7 months. After surgery, 48 patients (94%) returned to running at a mean of 8.5 ± 4.2 months. Patients who had discontinued running for more than 8 months before surgery had a longer return-to-running time than did those who had stopped for less than 8 months (10.6 ± 4.2 vs 7.6 ± 4.1 months; P = .01). After 2 years, mean preoperative distance had decreased significantly ( P < .01) from 9.5 ± 6.5 miles per week when healthy to 6.4 ± 5.8 miles postoperatively. Despite decreased mileage, all 2-year outcomes scores improved significantly ( P < .001). Conclusion: Recreational and competitive runners with FAI returned to running 94% of the time at a mean of 8.5 months after hip arthroscopy. However, runners should be counseled before their surgery that they may run fewer miles than when they were pain free. Additionally, patients with a higher BMI and/or longer preoperative lull may have a longer recovery time.

Purpose To determine whether the hip arthroscopy literature to date has shown outcomes consistent with published patient acceptable symptomatic state (PASS) and minimal clinically important difference (MCID) estimates. Methods All clinical investigations of hip arthroscopy using modified Harris Hip Score (mHHS) and/or Hip Outcome Score (HOS) outcomes with at least 1 year of follow-up were reviewed. Ninety-one studies (9,746 hips) were included for review. Eighty-one studies (9,317 hips) contained only primary hip arthroscopies and were the primary focus of this review. The remaining studies (429 hips) did not exclude patients with prior surgical history and were thus considered separately. Mean mHHS, HOS-ADL (Activities of Daily Living) and HOS-SS (Sports-Specific) scores were compared with previously published PASS and MCID values. Results After 31 ± 20 months, 5.8% of study populations required revision arthroscopy and 5.5% total hip arthroplasty. A total of 88%, 25%, and 30% of study populations met PASS for mHHS, HOS-ADL, and HOS-SS, respectively, and 97%, 90%, and 93% met MCID. On bivariate analysis, increasing age was associated with significantly worse postoperative mHHS ( P R 2 = 0.14), HOS-SS ( P = .05, R 2 = 0.12), and rates of reoperation ( P = .02, R 2 = 0.08). Increasing body mass index was associated with significantly worse HOS-ADL ( P = .02, R 2 = 0.35) and HOS-SS ( P = .03, R 2 = 0.30). Conclusions In this meta-analysis of 81 studies of primary hip arthroscopy, we have found that more than 90% of study populations meet MCID standards for the most commonly used patient-reported outcomes measures in hip arthroscopy literature, mHHS and HOS. Eighty-eight percent meet PASS standards for the mHHS, but PASS standards are far more difficult to achieve for HOS-ADL (25%) and HOS-SS (30%) subscales. Differences in psychometric properties of the mHHS and HOS likely account for the discrepancies in PASS. Level of Evidence Level IV, systematic review of Level I to IV studies.

Hip arthroscopy has experienced unprecedented growth in recent years and remains an area of booming technology and interest in orthopedic surgery. As understanding of the pathologic state of femoroacetabular impingement (FAI) has grown, imaging modalities have increased. Careful consideration of all bony and soft tissue structures in concert with physical examination findings in nonarthritic patients is necessary before any surgical intervention. This article summarizes the authors' approach to imaging in patients suspected of FAI, which facilitates careful patient selection and preoperative planning.

Abductor tendon tears typically develop insidiously in middle-aged women and can lead to debilitating lateral hip pain and a Trendelenburg limp. The gluteus medius tendon is most commonly torn and may show fatty degeneration over time, similar to the rotator cuff muscles of the shoulder. Endoscopic repair offers a therapeutic alternative to traditional open techniques. This article describes the workup, examination, and endoscopic repair of a full-thickness gluteus medius tear presenting as lateral hip pain and weakness. The surgical repair for this case used a single-row suture anchor technique. In addition, the indications and technique for a double-row repair will be discussed.

Objectives: Depression has been shown to have a negative effect on many orthopaedic surgical outcomes. The purpose of this study was to determine whether preoperative clinical diagnosis of depression and/or PROMIS (Patient-Reported Outcomes Measurement Information System) Depression scores predicted worse postoperative therapy compliance, functional outcomes, and return-to-sport after anterior cruciate ligament (ACL) reconstruction. Methods: A multi-surgeon series of consecutive patients who had undergone ACL reconstruction at a single institution between 1/4/16 and 7/19/16 were evaluated for inclusion. Patients who had completed preoperative PROMIS Depression (D), Physical Function (PF), and Pain Interference (PI) questionnaires were prospectively enrolled to complete minimum 2-year follow-up PROMIS and Return-to-Sport (ACL-RSI short-form) questionnaires. Chart review was conducted to determine depression diagnosis status, demographic data, and rehabilitation physical therapy (PT) compliance. PROMIS D score cutoff for mild depression was >52.5, based on previously established correlation to the validated Patient Health Questionnaire-9. Results: Ninety-five of 115 consecutive patients (81%) met inclusion criteria. Average follow-up was 34+/-1.9 months. Fourteen patients (15%) carried a clinical diagnosis of depression. Thirty-two (34%) had a preoperative PROMIS D score above the mild depression threshold; of those, 2 (2%) scored in the moderate depression range, and 3 (3%) scored in the severe depression range. Overall, the cohort (including depressed patients) showed improvement in PROMIS PF and PI scores postoperatively (p52.5) and undiagnosed depression patients (subgroup of preoperative PROMIS depressed without depression diagnosis) showed no difference in PT compliance or postoperative PROMIS PF or PI, compared to non-depressed patients (Table 2). Undiagnosed preoperative depressed patients (n=21/95 (22%)) also showed improvement in their depression scores postoperatively (mean PROMIS D = 57.4±5.0 preop vs. 44.5±6.6 postop; p0.05 for all). Conclusion: Clinically diagnosed depression is predictive of worse rehabilitation therapy compliance and worse functional outcomes after ACL reconstruction surgery, but even depressed patients can be expected to show improvement. PROMIS Depression scores, particularly in those without a clinical diagnosis of depression, can be expected to resolve to non-depressed range after ACL reconstruction. Patients with depressed mood preoperatively but no depression diagnosis could be considered to have “situational depression” and can be reassured that depression will likely resolve after ACL reconstruction. Patients with depression diagnosis, however, should be counseled regarding tempered expectations after ACL reconstruction. Resources should be allocated to incorporate behavioral health counseling pre- and post-surgery in an attempt to maximize outcomes.

Antegrade reamed intramedullary nailing has the advantages of high fracture union and early weight-bearing, making it the gold standard for fixation of diaphyseal femur fractures. However, knowledge of distal femoral anatomy may mitigate the risk of secondary complications. We present a previously unrecognized complication of antegrade femoral nailing in which a 23-year-old man sustained iatrogenic rupture of the medial patellofemoral ligament (MPFL) caused by the distal interlocking screw of the femoral nail. The patient had a history of antegrade intramedullary nailing that was revised for rotational malalignment, after which he began experiencing recurrent episodes of atraumatic bloody joint effusion and swelling of the right knee with associated patellar instability. Plain radiographs and magnetic resonance imaging revealed a large effusion with a prominent intra-articular distal interlocking screw disrupting the MPFL. The patient underwent a right knee arthroscopic-assisted MPFL reconstruction and removal of the distal interlocking screw. Following surgery, the patient experienced resolution of his effusions, no recurrent patellar instability, and was able to return to his activities. This case demonstrates that iatrogenic MPFL injury is a potential complication of antegrade femoral nailing and a previously unrecognized cause of patellar instability. Surgeons should be aware of this potential complication and strive to avoid the MPFL origin when placing their distal interlocking screw.

Background: Femoroacetabular impingement (FAI) is responsible for hip pain and dysfunction, and surgical outcomes depend on multiple factors. The presence of mental disorders negatively influences outcomes of multiple orthopaedic conditions, although the impact on FAI surgery is unclear. Hypothesis: The authors hypothesized that a preoperative self-reported history of mental disorders would negatively influence patient-reported outcome measures after FAI surgery. Study Design: Cohort study; Level of evidence, 3. Methods: A matched-cohort study was performed by reviewing a prospectively collected database of cases of arthroscopic management of FAI with a single surgeon over a 2-year period. Demographics and radiographic parameters were recorded for all patients. Patients completed the Hip Outcome Score–Activity of Daily Living Subscale (HOS-ADL), Hip Outcome Score–Sport-Specific Subscale (HOS-SSS), and modified Harris Hip Score (mHHS) prior to surgery and 2 years after surgery. Unpaired and paired t tests were used to compare results between and within cohorts at baseline and follow-up. Statistical significance was defined as P < .05. Results: The cohort included 301 patients, with 75 and 226 patients reporting and not reporting a history of mental disorders, respectively. Before treatment, all patient-reported outcome measures were significantly lower among patients reporting a history of mental disorders ( P < .01 for HOS-ADL, HOS-SSS, and mHHS). Patients in both groups demonstrated significant improvements ( P < .0001) in HOS-ADL, HOS-SSS, and mHHS when preoperative outcome measures were compared with follow-up. Patients with reported mental disorders had significantly lower scores after surgery as compared with patients without mental disorders ( P < .0001 for HOS-ADL, HOS-SSS, and mHHS). Conclusion: The presence of a reported mental disorder is associated with lower patient-reported outcomes before and after surgical management of FAI. Statistically significant and clinically relevant improvements were observed for patients who reported mental disorders. The magnitude of these improvements was not as large as that for an age- and sex-matched control group without a self-reported mental disorder.

OBJECT Infections following spine surgery negatively affect patient quality of life (QOL) and impose a significant financial burden on the health care system. Postoperative wound infections occur at higher rates following dorsal cervical procedures than ventral procedures. Quantifying the health outcomes and costs associated with infections following dorsal cervical procedures may help to guide treatment strategies to minimize the deleterious consequences of these infections. Therefore, the goals of this study were to determine the cost and QOL outcomes affecting patients who developed deep wound infections following subaxial dorsal cervical spine fusions. METHODS The authors identified 22 (4.0%) of 551 patients undergoing dorsal cervical fusions who developed deep wound infections requiring surgical debridement. These patients were individually matched with control patients who did not develop infections. Health outcomes were assessed using the EQ-5D, Pain Disability Questionnaire (PDQ), Patient Health Questionnaire (PHQ-9), and visual analog scale (VAS). QOL outcome measures were collected preoperatively and after 6 and 12 months. Health resource utilization was recorded from patient electronic medical records over an average follow-up of 18 months. Direct costs were estimated using Medicare national payment amounts, and indirect costs were based on patients' missed workdays and income. RESULTS No significant differences in preoperative QOL scores were found between the 2 cohorts. At 6 months postsurgery, the noninfection cohort had significant pre- to postoperative improvement in EQ-5D (p = 0.02), whereas the infection cohort did not (p = 0.2). The noninfection cohort also had a significantly higher 6-month postoperative EQ-5D scores than the infection cohort (p = 0.04). At 1 year postsurgery, there was no significant difference in EQ-5D scores between the groups. Health care–associated costs for the infection cohort were significantly higher ($16,970 vs $7658; p < 0.0001). Indirect costs for the infection cohort and the noninfection cohort were $6495 and $2756, respectively (p = 0.03). Adjusted for inflation, the total costs for the infection cohort were $21,778 compared with $9159 for the noninfection cohort, reflecting an average cost of $12,619 associated with developing a postoperative deep wound infection (p < 0.0001). CONCLUSIONS Dorsal cervical infections temporarily decrease patient QOL postoperatively, but with no long-term impact; they do, however, dramatically increase the cost of care. Knowledge of the financial burden of wound infections following dorsal cervical fusion may stimulate the development and use of improved prophylactic and therapeutic techniques to manage this serious complication.

Hip preservation surgery has become more common over the past decade and is now a preferred treatment modality for an increasingly diverse array of pathology in the young, active patient with hip pain. In particular, hip arthroscopy has become an increasingly popular treatment choice for active patients diagnosed with femoroacetabular impingement (FAI). Appropriate postoperative rehabilitation is critical for overall patient success and optimal long-term outcome. As surgical techniques continue to evolve, rehabilitation protocols must adapt to accommodate changes in the surgical procedure and ultimately provide the safest and fastest recovery of function for the patient. One such surgical modification has been the incorporation of routine capsular closure as part of the treatment of FAI in the young, active patient. The purpose of this clinical commentary is to present a four-phase rehabilitation protocol for returning to sport following arthroscopic correction of FAI with routine capsular closure.5.

Our understanding of patients' desired outcomes and expectations of arthroscopic rotator cuff repair (ARCR) is limited, particularly regarding the importance of pain relief and strength return relative to each other. We conducted a study of patient's ratings of the importance of pain relief and strength return after ARCR. Before undergoing surgery, 60 patients completed a shoulder questionnaire on which they assessed severity of symptoms and rated, on a 10-point scale, the importance of postoperative improvements in pain relief and strength return. After surgery, they completed the same questionnaire, again rating the importance of pain relief and strength return. About 50% of the patients valued pain relief and strength return equally before and after ARCR. However, overall patient ratings were higher for strength return over pain relief, both before surgery, mean (SD), 9.2 (2.1) vs 8.6 (2.3) (P = .02), and afterward, at a follow-up of 5.2 (0.2) years, 8.9 (1.9) vs 8.2 (3.1) (P = .03). This significant preference for strength return held irrespective of sex, age, active sports involvement, preoperative self-assessed pain score, and subjective shoulder weakness. Before surgery, increasing age was associated with a stronger preference for pain relief (r = 0.33, P = .01), and retirees preferred pain relief over strength return. These results show the patterns of patient preference for pain relief and strength return after ARCR. Improved understanding of these patients' expectations will allow meaningful changes in patient satisfaction.

Objectives: Growing biomechanical and clinical evidence suggests that the treating hip arthroscopist must balance creating a capsulotomy large enough to adequately address underlying pathology while not compromising the integrity of the hip capsule, which can potentially lead to iatrogenic hip instability. The purpose of this study was to compare the cross-sectional area (CSA) of joint visualization between interportal and T-capsulotomies. Methods: 12 fresh-frozen cadaveric hips were dissected to their capsuloligamentous complexes and fixed in a custom apparatus in neutral hip position. Eight hips underwent sequential interportal capsulotomies at lengths of 2, 4, 6, and 8 cm. Four hips underwent sequential T-capsulotomies, 4 cm interportal and 2 cm T-capsulotomy (Half-T), then expansion of the T-capsulotomy to 4 cm (Full-T). A high-resolution digital photograph was taken of the capsulotomies from a standardized distance and angle with a calibration marker in place. Joint exposure gained from each capsulotomy was determined by measuring joint cross-sectional area (CSA) with ImageJ software (NIH, Bethesda, MD). Comparisons were made using t-tests and analysis of variance (ANOVA). Results: There was no significant difference in the age of cadaveric hips in both groups (65.6 ± 10.83 years: interportal vs 63.3 ± 2.5 years: T capsulotomy, p=0.53). There was statistically significant increase in CSA visualization with each increase in length (2cm: 0.58 ± 0.21cm2; 4cm: 2.14 ± 0.48 cm2; 6cm: 3.57±0.96 cm2; and 8cm: 4.22 ± 1.16 cm2, pConclusion: When improved joint exposure is necessary, T-capsulotomy should be considered given the decreased morbidity of cutting the IFL inline with its fibers and the significantly increased joint visualization compared to extending the interportal capsulotomy.

Background context Cervical disc arthroplasty (CDA) is a motion-preserving procedure that is an alternative to fusion. Proponents of arthroplasty assert that it will maintain cervical motion and prevent or reduce adjacent segment degeneration. Accordingly, CDA, compared with fusion, would have the potential to improve clinical outcomes. Published studies have varying conclusions on whether CDA reduces complications and/or improves outcomes. As many of these previous studies have been funded by CDA manufacturers, we wanted to ascertain whether there was a greater likelihood for these studies to report positive results. Purpose To critically assess the available literature on cervical arthroplasty with a focus on the time of publication and conflict of interest (COI). Study design/setting Review of the literature. Methods All clinical articles about CDA published in English through August 1, 2013 were identified on Medline. Any article that presented CDA clinical results was included. Study design, sample size, type of disc, length of follow-up, use of statistical analysis, quality-of-life (QOL) outcome scores, COI, and complications were recorded. A meta-analysis was conducted stratifying studies by COI and publication date to identify differences in complication rates reported. Results Seventy-four studies were included that investigated 8 types of disc prosthesis and 22 met the criteria for a randomized controlled trial (RCT). All Level Ib RCTs reported superior quality-of-life outcomes for CDA versus anterior cervical discectomy and fusion (ACDF) at 24 months. Fifty of the 74 articles (68%) had a disclosure section, including all Level Ib RCTs, which had significant COIs related to the respective studies. Those studies without a COI reported mean weighted average adjacent segment disease rates of 6.3% with CDA and 6.2% with ACDF. In contrast, the reverse was reported by studies with a COI, for which the averages were 2.5% with CDA and 6.3% with ACDF. Those studies with a COI (n=31) had an overall weighted average heterotopic ossification rate of 22%, whereas those studies with no COI (n=43) had a rate of 46%. Conclusions Associated COIs did not influence QOL outcomes. Conflicts of interest were more likely to be present in studies published after 2008, and those with a COI reported greater adjacent segment disease rates for ACDF than CDA. In addition, heterotopic ossification rates were much lower in studies with COI versus those without COI. Thus, COIs did not affect QOL outcomes but were associated with lower complication rates.

The objective of this study was to determine if adolescent and young adult patients undergoing hip arthroscopy for symptomatic femoroacetabular impingement (FAI) experience clinically meaningful improvements in functional outcome scores. A consecutive series of patients under age 18 who underwent primary hip arthroscopy for symptomatic FAI was identified using our institution’s hip registry. Demographics, preoperative radiographic measurements, and preoperative and postoperative patient-reported outcome scores [Hip Outcome Score (HOS), Activity of Daily Living (ADL), and Sports-Specific Subscale (SS), and modified Harris Hip Score (MHHS)] were collected. Percentage of patients achieving minimum clinically important difference (MCID) and patient acceptable symptom state (PASS) were determined using published cutoffs for HOS and MHHS in FAI patients. Forty-three patients met study inclusion criteria, and 37 patients (86%) were available at a minimum follow-up of 2 years. Mean age was 17.0±1.4 years, 70% were female, and 8.1% had an open proximal femoral physis. All competitive high school and college athletes were able to return to sport. Patients experienced significant improvements following hip arthroscopy in HOS-ADL, HOS-SS, and MHHS scores (all P

The use of biologic adjuvants in the treatment of operative and nonoperative orthopedic injuries continues to expand in concert with our understanding of the acute and chronic healing process of musculoskeletal injuries. Stem cell treatments in orthopedics are among the most commonly explored options, and have found varying levels of success in promoting osseous and soft tissue healing. Basic science and translational studies have demonstrated the potential for broad application of stem cells in the treatment of a growing number of musculoskeletal injuries. Emerging clinical studies have also provided promising results, although the vast majority of studies have featured small sample sizes and limited duration of follow-up. In addition, a number of important questions remain regarding the clinical safety, treatment delivery, and overall efficacy of stem cell augmentation of injured tissue in orthopedics. The objective of the current review is to present a broad overview of the current state of stem cell treatments in orthopedic surgery, with an emphasis on soft tissue healing. This review of stem cell treatment covers the basic science behind biologic augmentation, advantages of the various stem cell sources, preclinical results, and current and future clinical applications.

To quantify how increasing interportal capsulotomy size affects the force required to distract the hip and to biomechanically compare simple side-to-side suture repair to acetabular-based suture anchors as capsular repair techniques.Twelve fresh-frozen cadaveric hip specimens were dissected to the capsuloligamentous complex of the hip joint and fixed in a material testing system, such that a pure axial distraction of the iliofemoral ligament could be achieved. After each hip in was tested an intact state, sequential distraction was tested with 2, 4, 6, and 8 cm capsulotomies. Specimens were assigned randomly to be repaired with either 4 side-to-side suture repair (n = 6) or 2 double-loaded all-suture anchors (n = 6). The distraction force as well as the relative distraction force percentage normalized to the intact capsule were compared between suture repair and suture anchor repair groups.Increasing the size of the capsulotomy resulted in less force required to distract the hip to 6 mm. The force decreased as the capsulotomy was extended with statistical significance in distraction force seen between the intact state and the 4 cm (P = .003), 6 cm (P.001), and 8 cm (P ≤ .001) capsulotomy but not for the intact state compared to the 2 cm capsulotomy (P = .28). Statistical significance in relative distraction force was seen for each of the capsulotomy conditions (P.001 for all conditions compared with the intact state). The side-to-side suture repair construct (104.3% of intact force) required greater force to distraction to 6 mm compared with the suture anchor repair (87.1% of intact force) (P = .008).An interportal capsulotomy significantly affected the force required to distract the hip in a cadaveric model, with the larger the size of capsulotomy resulting in less force required to distract the hip. When we performed an interportal capsulotomy, the iliofemoral ligament strength was altered significantly but capsular repair with either side-to-side sutures or suture anchor-based repair was able to restore the capsular strength to a native intact hip. We found, however, that the side-to-side suture repair was better able to restore the distraction force compared with suture anchor repair.Capsular management during hip arthroscopy remains a debated topic, with multiple techniques involving both capsulotomy and capsular closure published in the literature. This study provides insight into capsular stability against axial stress under capsulotomy and capsular repair conditions.

To compare the return-to-play rates, patient-reported outcome (PRO) scores, and satisfaction between high-level amateur athletes and recreational athletes and to evaluate for differences in ability to return to sport in these groups based on patient-related and sport-related characteristics.Clinical data were retrieved for 66 (26 male/40 female) consecutive athletes undergoing hip arthroscopy for femoroacetabular impingement. Athletes were classified as high-level amateur or recreational. Athletes were also divided into 6 distinct sporting categories based on the physical demands on the hip. Preoperative and 2-year PROs including a sport-specific questionnaire, modified Harris Hip Score (MHHS), and Hip Outcome Scores with Activities of Daily Living (HOS-ADL) and Sports-Specific (HOS-SS) subscales were collected.Of the 66 patients, 49 were recreational and 17 were high-level amateur athletes (10 high school and 7 collegiate). High-level athletes were significantly younger than recreational athletes (18.4 ± 2.3 years vs 29.7 ± 6.8 years; P.001). After 2 years, all PROs had improved significantly, with no differences between the 2 athletic groups. There was a high overall rate of return for both recreational and high-level amateur athletes (94% vs 88%; P = .60). Increasing preoperative withdrawal time from sport prior to surgery was associated with decreased HOS-SS (r = 0.33; P = .04) and MHHS scores (r = 0.02; P = .02). Overall, athletes who had withdrawn from sport for greater than 8 months before surgery returned to sport significantly more slowly (P = .01). Increasing body mass index (BMI) was associated with lower improvements in HOS (r = 0.26; P = .04) and MHHS scores (r = 0.38; P.01).Recreational athletes, despite being significantly older than their high-level counterparts, return to play at a similar high rate and with comparable PROs. Increasing preoperative cessation time from sport significantly prolongs return to sport. Additionally, increasing preoperative cessation from sport and higher preoperative BMI were associated with decreased improvements in PROs.Level III, retrospective comparative study.

Hip arthroscopy has become an increasingly utilized surgical technique for the treatment of the young, active patients with hip pain. The clinical outcomes of hip arthroscopy in this patient population have been largely successful; however, there is increasing interest in the contribution of hip capsule in postoperative clinical and functional outcomes. The structure and function of the normal hip capsule will be reviewed. Capsular contributions to hip stability will be discussed in the setting of hip arthroscopy with an emphasis on diagnosis-based considerations. Lastly, clinical outcomes following hip arthroscopy will be discussed as they relate to capsular management.

Femoroacetabular impingement (FAI) is a common cause of hip pain, and when indicated, can be successfully managed through open surgery or hip arthroscopy. The goal of this review is to describe the different approaches to the surgical treatment of FAI. We present the indications, surgical technique, rehabilitation, and complications associated with (1) open hip dislocation, (2) reverse peri-acetabular osteotomy, (3) the direct anterior “mini-open” approach, and (4) arthroscopic surgery for femoroacetabular impingement.

Femoroacetabular impingement (FAI) is a clinical syndrome resulting from abnormal hip joint morphology and is a common cause of hip pain in young adults. FAI has been posited as a precursor to hip osteoarthritis, however, conflicting evidence exists and the true natural history of the disease is unclear. The purpose of this article is to review the current understanding of how FAI damages the hip joint by highlighting its pathomechanics and etiology. We then review the current evidence relating FAI to osteoarthritis. Lastly, we will discuss the potential of hip preservation surgery to alter the natural history of FAI, reduce the risk of developing osteoarthritis and the need for future arthroplasty.

Growing awareness of femoroacetabular impingement (FAI) and recent innovations in management have resulted in hip arthroscopy becoming one of the fastest-growing orthopedic subspecialties. The purpose of this study was to identify the 50 most cited articles related to the topic of FAI and hip arthroscopy and to analyze their characteristics. The overall number of citations within these articles ranged from 99 to 820. Citation density ranged from 4.41 to 74.55. Seven countries produced these articles with the majority attributed to the United States (n = 26) and Switzerland (n = 18). Clinical studies made up more than half of the top articles (n = 27). The Journal of Bone and Joint Surgery level of evidence most commonly encountered was level IV (n = 24), while the remaining articles were level III (n = 3). No randomized controlled trials or non-randomized controlled trials were encountered in this search. The level of evidence was not significantly correlated with the overall number of citations, publication year, or citation density. The current top 50 list provides orthopedic surgeons interested in hip arthroscopy with an up-to-date core list of the most cited articles in the scientific literature and represents a foundation to use to develop their knowledge regarding hip arthroscopy and FAI.

Hip distraction is necessary for safe arthroscopic entry into the hip joint. Achieving sufficient distraction is difficult in exceedingly tall patients (>190.5 cm) because of size limitations of currently available hip distraction systems. Inadequate distraction can delay the surgical procedure and potentially lead to complications. By repurposing a foam head-positioning block, we report a safe and inexpensive positioning technique for extending the traction distance for tall patients by 2 inches.

Despite their value as sources of therapeutic drug targets, membrane proteomes are largely inaccessible to high-throughput screening (HTS) tools designed for soluble proteins. An important example comprises the membrane proteins that bind amyloid β oligomers (AβOs). AβOs are neurotoxic ligands thought to instigate the synapse damage that leads to Alzheimer's dementia. At present, the identities of initial AβO binding sites are highly uncertain, largely because of extensive protein-protein interactions that occur following attachment of AβOs to surface membranes. Here, we show that AβO binding sites can be obtained in a state suitable for unbiased HTS by encapsulating the solubilized synaptic membrane proteome into nanoscale lipid bilayers (Nanodiscs). This method gives a soluble membrane protein library (SMPL)--a collection of individualized synaptic proteins in a soluble state. Proteins within SMPL Nanodiscs showed enzymatic and ligand binding activity consistent with conformational integrity. AβOs were found to bind SMPL Nanodiscs with high affinity and specificity, with binding dependent on intact synaptic membrane proteins, and selective for the higher molecular weight oligomers known to accumulate at synapses. Combining SMPL Nanodiscs with a mix-incubate-read chemiluminescence assay provided a solution-based HTS platform to discover antagonists of AβO binding. Screening a library of 2700 drug-like compounds and natural products yielded one compound that potently reduced AβO binding to SMPL Nanodiscs, synaptosomes, and synapses in nerve cell cultures. Although not a therapeutic candidate, this small molecule inhibitor of synaptic AβO binding will provide a useful experimental antagonist for future mechanistic studies of AβOs in Alzheimer's model systems. Overall, results provide proof of concept for using SMPLs in high throughput screening for AβO binding antagonists, and illustrate in general how a SMPL Nanodisc system can facilitate drug discovery for membrane protein targets.

Lumbar degenerative spondylolisthesis (LDS) is often diagnosed by conventional supine magnetic resonance imaging (MRI). Numerous studies have shown, however, that the degree of spondylolisthesis can be reduced or disappears when the patient is supine as compared with standing lateral and flexion-extension (SLFE) radiographs.To compare the sensitivity of supine MRI with SLFE radiographs in patients with L4-L5 LDS.A retrospective imaging study.Included patients diagnosed with L4-L5 LDS with both SLFE films and supine MRI.Lumbar degenerative spondylolisthesis was defined radiographically as a slip greater than 4.5 mm. Mobile LDS was defined as a difference of greater than 3% in slip percentage between lateral radiographs and sagittal MRIs. Additional measurements included L4-L5 facet effusion diameter on axial MRIs. Measurements were performed by two independent examiners. The kappa coefficient was used to assess the interobserver agreement.Of 103 patients assessed, 68% were women and the average age was 66 years. Lumbar degenerative spondylolisthesis was seen on 101 (98%) lateral films and 80 (78%) MRIs. Average slip was 10.0 mm for lateral standing radiographs and 6.6 mm on MRI (p.0001). Fifty (48%) patients were identified with mobile LDS. The positive predictive value of facet joint effusion for mobile LDS increased from 52% for effusions greater than 1 mm to 100% for effusions greater than 3.5 mm.This study found that MRI had a sensitivity of 78% for detecting L4-L5 LDS compared with 98% for lateral standing films. We also identified facet effusion size as a marker to predict mobile LDS. These findings suggest that, particularly in the setting of facet effusions, the complete workup of patients in whom LDS is possible should include standing radiographs.

Objectives: The objective of this study was to identify the location and magnitude of difference in acetabular rim morphology between the symptomatic and asymptomatic acetabula in a cohort of patients with symptomatic unilateral pincer-type FAI. Methods: After IRB approval, computed tomography (CT) scans of 43 patients (22 males, 21 females) diagnosed with unilateral pincer-type FAI were obtained. CT images of both hips were imported in DICOM format and segmented into 3-dimensional (3D) hemi-pelvises using 3D reconstruction software (Mimics, Materialise, Leuven, Belgium). The point-cloud data of the asymptomatic hemi-pelvis was mirrored onto the symptomatic side. Protrusion of the symptomatic side was recorded as a positive value and appeared as red on the color map (Figure 1). Data was collected in 3° intervals and analyzed by quadrant using the clock face method; reflecting the 12-3, 3-6, 6-9, and 9-12 o’clock positions. Results: The symptomatic acetabular rim was on average 0.39 ± 0.36 mm thicker than the corresponding location on the asymptomatic rim. When the acetabular clock face was broken up into quadrants, reflecting the 12-3, 3-6, 6-9, and 9-12 o’clock positions, the 12-3 o’clock position demonstrated the greatest difference between symptomatic and asymptomatic sides (Table 1). The 12-3 o’clock quadrant demonstrated significantly greater difference between symptomatic and asymptomatic sides (0.53±0.22 mm) as compared to the 3-6 o’clock position (0.39±0.27 mm; p=0.006), the 6-9 o’clock position (0.34±0.05 mm; pConclusion: Small changes in acetabular rim morphology, on the order of 0.5 mm or less can be the difference between symptomatic pincer-type FAI and the asymptomatic state. Knowledge of the healthy, unaffected side in unilateral FAI may provide a better template for rim recession rather than broadly applying previously described anterior or lateral center-edge angle parameters.