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Background: The glenoid track concept has been widely used to assess the risk of instability caused by a bipolar lesion. The mean glenoid track width is reported to be 83% of the glenoid width. However, this width seems to be affected by the range of motion of the shoulder. By clarifying the relationship between the range of shoulder motion and the glenoid track width, a more precise determination of the glenoid track width for each individual could be possible. Purpose: To determine the relationship between the glenoid track width and the range of motion of healthy volunteers. Study Design: Descriptive laboratory study. Methods: Magnetic resonance imaging was taken in 41 shoulders of 21 healthy volunteers (mean age, 32 years) with the arm in maximum horizontal extension, with the arm kept in 90° of abduction and 90° of external rotation. Three-dimensional surface bone models of the glenoid and the humerus were created with image analysis software. The distance from the anterior rim of the glenoid to the medial margin of the footprint of the rotator cuff tendon was defined as the glenoid track width. Active and passive ranges of shoulder motion were measured in the supine and sitting positions. The correlations between the glenoid track width and the ranges of shoulder motion were investigated with Pearson correlation coefficients. Intra- and interobserver reliabilities based on the intraclass correlation coefficient were also analyzed to assess the reliability of the glenoid track measurement. Results: The intra- and interobserver reliabilities for the glenoid track measurement were excellent (0.988 and 0.988, respectively). Among all the measurements, the glenoid track width and the active range of motion in horizontal extension in the sitting position showed the greatest correlation coefficient (r = −0.623, P < .0001). A correlation between the glenoid track width and this angle was expressed as Y = −0.49X + 90, where X is the horizontal extension angle (degrees) and Y is the glenoid track width (percentage of glenoid width). Conclusion: The present data demonstrate that the greater the horizontal extension angle in abduction and external rotation, the smaller the glenoid track width. An individualized glenoid track width can be obtained by measuring the active horizontal extension angle with the arm in abduction and external rotation in the sitting position. Clinical Relevance: An individualized glenoid track width enables selection of a more precise surgical option by the on-track/off-track concept. [ABSTRACT FROM AUTHOR]

Background: The ulnar collateral ligament (UCL) microstructural organization and collagen fiber realignment in response to load are unknown. Purpose/Hypothesis: The purpose was to describe the real-time microstructural collagen changes in the anterior bundle (AB) and posterior bundle (PB) of the UCL with tensile load. It was hypothesized that the UCL AB is stronger and stiffer with more highly aligned collagen during loading when compared with the UCL PB. Study Design: Descriptive laboratory study. Methods: The AB and PB from 34 fresh cadaveric specimens were longitudinally sectioned to allow uniform light passage for quantitative polarized light imaging. Specimens were secured to a tensile test machine and underwent cyclic preconditioning, a ramp-and-hold stress-relaxation test, and a quasi-static ramp to failure. A division-of-focal-plane polarization camera captured real-time pixelwise microstructural data of each sample during stress-relaxation and at the zero, transition, and linear points of the stress-strain curve. The SD of the angle of polarization determined the deviation of the average direction of collagen fibers in the tissue, while the average degree of linear polarization evaluated the strength of collagen alignment in those directions. Since the data were nonnormally distributed, the median ± interquartile range are presented. Results: The AB has larger elastic moduli than the PB (P < .0001) in the toe region (median, 2.73 MPa [interquartile range, 1.1-5.6 MPa] vs 0.65 MPa [0.44-1.5 MPa]) and the linear region (13.77 MPa [4.8-40.7 MPa] vs 1.96 MPa [0.58-9.3 MPa]). The AB demonstrated larger stress values, stronger collagen alignment, and more uniform collagen organization during stress-relaxation. PB collagen fibers were more disorganized than the AB during the zero (P = .046), transitional (P = .011), and linear (P = .007) regions of the stress-strain curve. Both UCL bundles exhibited very small changes in collagen alignment (SD of the angle of polarization) with load. Conclusion: The AB of the UCL is stiffer and stronger, with more strongly aligned and more uniformly oriented collagen fibers, than the PB. The small changes in collagen alignment indicate that the UCL response to load is due more to its static collagen organization than to dynamic changes in collagen alignment. Clinical Relevance: The UCL collagen organization may explain its susceptibility to injury with repetitive valgus loads. [ABSTRACT FROM AUTHOR]

Background: Recent literature correlated anterior cruciate ligament (ACL) reconstruction failure to smaller diameter of the harvested hamstring (HS) autograft. However, this approach may be a simplification, as relation of graft size to native ACL size is not typically assessed and oversized grafts may impart their own complications. Purpose: To evaluate in vivo data to determine if the commonly used autografts reliably restore native ACL size. Study Design: Descriptive laboratory study. Methods: Intraoperative data of the tibial insertion area and HS graft diameter were collected and retrospectively evaluated for 46 patients who underwent ACL reconstruction with HS autografts. Magnetic resonance imaging measurements of the cross-sectional area (CSA) of the possible patellar tendon (PT) and quadriceps tendon (QT) autografts were also done for each patient. The percentages of tibial insertion site area restored by the 3 possible grafts were then calculated and compared for each individual. Results: The mean ACL tibial insertion area was 107.2 mm2 (60.5-155.5 mm2). The mean CSAs of PT, HS, and QT were 33.2, 55.3, and 71.4 mm2, respectively. When all grafts were evaluated, the percentage reconstruction of the insertion area varied from 16.2% to 123.1% on the tibial site and from 25.5% to 176.7% on the femoral site, differing significantly for each graft type (P < .05). On average, 32.8% of the tibial insertion area would have been filled with PT, 53.6% by HS, and 69.5% by QT. Based on previous cadaveric studies indicating that graft size goal should be 50.2% ± 15% of the tibial insertion area, 82.7% of patients in the HS group were within this range (36.9%, QT; 30.5%, PT), while 65.2% in the PT group were below it and 60.9% in the QT group were above it. Conclusion: ACL insertion size and the CSAs of 3 commonly used grafts vary greatly for each patient and are not correlated with one another. Thus, if the reconstructed ACL size is determined by the harvested autograft size alone, native ACL size may not be adequately restored. PT grafts tended to undersize the native ACL, while QT might oversize it. Clinical Relevance: These results may help surgeons in preoperative planning, as magnetic resonance imaging measurements can be helpful in determining individualized graft choice to adequately restore the native ACL. [ABSTRACT FROM AUTHOR]

Cam morphology of the proximal femur is an abnormal contour of the femoral head-neck junction present in approximately 15% to 25% of the asymptomatic population, predominantly in males. Alpha angle and femoral head-neck offset ratio are 2 objective measurement tools that define cam morphology. Both primary (idiopathic) and secondary cam deformity develops through distinct mechanisms. The cause of primary (idiopathic) cam morphology remains incompletely understood. Mounting evidence suggests that idiopathic cam morphology develops during adolescence through alterations in the capital femoral epiphysis in response to participation in vigorous sporting activity. While the exact cause of epiphyseal extension has not yet been determined, preliminary evidence suggests that epiphyseal extension may reflect a short-term adaptive response to provide stability to the physis at the long-term cost of the development of cam morphology. Commonly recognized causes of secondary cam deformity include frank slipped capital femoral epiphysis, Legg-Calve-Perthes disease, and deformity after fracture of the proximal femur. Recent studies also support subtle slipped capital femoral epiphysis as a unique and silent cause of a small percentage of subjects previously thought to have idiopathic cam deformity. [ABSTRACT FROM AUTHOR]

The anterolateral ligament (ALL) of the knee has gained attention recently for its potential role in rotational stability of the knee, especially in association with anterior cruciate ligament (ACL) injuries. Anatomic studies have characterized the ALL as it runs in an anteroinferior and oblique direction from the lateral distal femur to the anterolateral proximal tibia, although the prevalence and variance of this ligament are not well understood. Magnetic resonance imaging and ultrasound have identified the ligament and linked it with the classically described Segond fracture. While the ALL likely plays a role in rotational stability of the knee, further studies investigating the significance of ALL injuries and the role of ALL reconstruction in combination with ACL reconstruction are warranted. [ABSTRACT FROM AUTHOR]

Background: It is unknown whether the height of a heel-rise performed in the single-leg standing heel-rise test 1 year after an Achilles tendon rupture (ATR) correlates with ankle biomechanics during walking, jogging, and jumping in the long-term. Purpose: To explore the differences in ankle biomechanics, tendon length, calf muscle recovery, and patient-reported outcomes at a mean of 6 years after ATR between 2 groups that, at 1-year follow-up, had less than 15% versus greater than 30% differences in heel-rise height. Study Design: Cohort study; Level of evidence, 3. Methods: Seventeen patients with less than 15% (<15% group) and 17 patients with greater than 30% (>30% group) side-to-side difference in heel-rise height at 1 year after ATR were evaluated at a mean (SD) 6.1 (2.0) years after their ATR. Ankle kinematics and kinetics were sampled via standard motion capture procedures during walking, jogging, and jumping. Patient-reported outcome was evaluated with Achilles tendon Total Rupture Score (ATRS), Physical Activity Scale (PAS), and Foot and Ankle Outcome Score (FAOS). Tendon length was evaluated by ultrasonography. The Limb Symmetry Index (LSI = [Injured Side ÷ Healthy Side] × 100) was calculated for side differences. Results: The >30% group had significantly more deficits in ankle kinetics during all activities compared with patients in the <15% group at a mean of 6 years after ATR (LSI, 70%-149% and 84%-106%, respectively; P = .010-.024). The >30% group, compared with the <15% group, also had significantly lower values in heel-rise height (LSI, 72% and 95%, respectively; P < .001) and heel-rise work (LSI, 58% and 91%, respectively; P < .001) and significantly larger side-to-side difference in tendon length (114% and 106%, respectively; P = .012). Achilles tendon length correlated with ankle kinematic variables (r = 0.38-0.44; P = .015-.027) whereas heel-rise work correlated with kinetic variables (r = −0.57 to 0.56; P = .001-.047). LSI tendon length correlated negatively with LSI heel-rise height (r = −0.41; P = .018). No differences were found between groups in patient-reported outcome (P = .143-.852). Conclusion: Height obtained during the single-leg standing heel-rise test performed 1 year after ATR related to the long-term ability to regain normal ankle biomechanics. Minimizing tendon elongation and regaining heel-rise height may be important for the long-term recovery of ankle biomechanics, particularly during more demanding activities such as jumping. [ABSTRACT FROM AUTHOR]

Background: Recent studies have shown a correlation between scapular geometry and the development of atraumatic rotator cuff tears. However, a paucity of literature is available on the effects of critical shoulder angle (CSA) and acromial index (AI) on functional outcomes after arthroscopic rotator cuff repair. Hypothesis/Purpose: The purpose was to investigate the influence of CSA and AI on 24-month functional outcomes after arthroscopic rotator cuff repair. The hypothesis was that a larger CSA or AI would result in poorer postoperative outcomes. Study Design: Cohort study; Level of evidence, 3. Methods: The study included 147 patients who underwent arthroscopic double-row rotator cuff repair for radiologically documented full-thickness supraspinatus tears. An independent reviewer measured the CSA and AI on preoperative radiographs. These patients were prospectively enrolled and were evaluated preoperatively as well as at 3, 6, 12, and 24 months postoperatively. Functional outcome was assessed with the Constant Shoulder Score (CSS), Oxford Shoulder Score (OSS), and University of California at Los Angeles (UCLA) Shoulder Rating Scale. The patients were first divided based on CSA: (1) ≤35° (control CSA) and (2) >35° (increased CSA); and then based on AI: (1) ≤0.7 and (2) >0.7. The Student unpaired t test, Pearson chi-square test, and Pearson correlation were performed to examine the influence of CSA and AI on postoperative functional outcome scores. Results: At 6 months of follow-up, the CSS, OSS, and UCLA Shoulder Rating Scale were 10 ± 1, 4 ± 2, and 3 ± 1 points poorer in the increased CSA group compared with the control CSA group (P = .005, P = .030, and P = .035, respectively). These scores were not significantly different between both AI groups. By 24 months of follow-up, all outcome scores were comparable between both CSA groups as well as between both AI groups. No significant correlation was found between either CSA or AI when compared with CSS, OSS, or UCLA Shoulder Rating Scale at 24 months of follow-up. Conclusion: CSA and AI do not appear to influence 24-month functional outcomes postoperatively and hence are not contraindications to arthroscopic rotator cuff repair. [ABSTRACT FROM AUTHOR]

Background: Patellofemoral pain (PFP) is a prevalent disorder among female adolescents. Overuse is frequently cited as the cause of pain for this population. What is currently unclear, however, is if the patella demonstrates abnormal tracking patterns relative to the femoral trochlear groove in female adolescents with PFP. Purpose: The aim of this case-control study was to determine if abnormal patellar tracking patterns are present in female adolescents with PFP. The secondary aim was to identify if an increased tibial tuberosity-trochlear groove (TT-TG) distance is associated with the observed kinematic patterns. Study Design: Controlled laboratory study. Methods: Twenty female adolescent knees from 12 patients with PFP and 20 age-matched female knees from 13 healthy controls were recruited for this study. Patellofemoral kinematics (eg, lateral patellar displacement) during a repetitive knee extension-flexion maneuver was quantified by dynamic cine phase-contrast magnetic resonance imaging (MRI). Static MRI scans were used to determine the TT-TG distance. Results: Relative to the control cohort, female adolescents with PFP demonstrated significantly greater lateral displacement at 10° (3.2 mm; P < .001), 20° (2.3 mm; P < .001), and 30° (1.7 mm; P = .014) of knee flexion. A subgroup within this cohort (7 knees from 5 patients) demonstrated extreme lateral maltracking >2 SDs of the mean of the control cohort. This subgroup also demonstrated a greater TT-TG distance relative to the controls (Δ = 4.2 mm; P = .001). Conclusion: This study demonstrates abnormal lateral patellar displacement in the absence of patellar tilt in female adolescents with PFP. Because all adolescents from both cohorts participated in impact sports, it appears that rigorous athletic training alone is inadequate to produce symptoms in this population. Rather, PFP may derive from a combination of physical activity in the context of pathological kinematics. Clinical Relevance: Abnormal patellar tracking patterns and abnormal static alignment have been shown to contribute to the etiology of patellofemoral pain in adults. This study demonstrates that pathologic patellar tracking patterns are present in adolescent females with patellofemoral pain. [ABSTRACT FROM AUTHOR]

Background: Abnormal glenoid version is a risk factor for shoulder instability. However, the degree to which the variance in version (both anteversion and retroversion) affects one’s predisposition for instability is not well understood. Purpose: To determine the influence of glenoid version on anterior shoulder joint stability and to determine if the direction of the humeral head dislocation is a stimulus for the development of Hill-Sachs lesions. Study Design: Controlled laboratory study. Methods: Ten human cadaveric shoulders (mean age, 59.4 ± 4.3 years) were tested using a custom shoulder dislocation device placed in a position of apprehension (90° of abduction with 90° of external rotation). Glenoid version was adjusted in 5° increments for a total of 6 version angles tested: +10°, +5°, 0°, −5°, −10°, and −15° (anteversion angles are positive, and retroversion angles are negative). Two humeral dislocation directions were tested. The first direction was true anterior through the anterior-posterior glenoid axis. The second dislocation direction was 35° inferior from the anterior-posterior glenoid axis based on the deforming force role of the pectoralis major. The force and energy to dislocate were recorded. Results: Changes in glenoid version manifested a linear effect on the dislocation force. The energy to dislocate increased as a second-order polynomial as a function of increasing glenoid retroversion. Glenoid version of +10° anteversion and −15° retroversion was highly unstable, resulting in spontaneous dislocation in one-quarter (10/40) and one-half (25/40) of the specimens anteriorly and posteriorly, respectively, in the absence of an applied dislocation force. The greater tuberosity was observed to engage with the anterior glenoid rim, consistent with Hill-Sachs lesions, 40% more frequently when the dislocation direction was true anterior compared with 35° inferior from the anterior-posterior glenoid axis. The engagement of the greater tuberosity caused an increase in the energy required to dislocate. Conclusion: Glenoid version has a direct effect on the force required for a dislocation. An anterior-inferior dislocation direction requires less energy for a dislocation and results in a lower risk of the development of a Hill-Sachs lesion than a direct anterior dislocation direction. Clinical Relevance: Consideration should be given to glenoid version when choosing a surgical treatment option for anterior shoulder instability. [ABSTRACT FROM AUTHOR]

Background: The anteromedial (AM) bundle of the anterior cruciate ligament (ACL) has a higher modulus and failure stress than does the posterolateral (PL) bundle. However, it is unknown how these properties vary within each bundle. Purpose: To quantify mechanical and microstructural properties of samples within ACL bundles to elucidate any regional variation across the ligament. We hypothesized that there are no differences within each bundle in contrast to cross-bundle variation. Study Design: Descriptive laboratory study. Methods: Sixteen human ACLs were dissected into AM and PL bundles. Three samples were taken from each bundle in an ordered sequence from AM (region 1 AM bundle) to PL (region 6 PL bundle). Each sample was tested in uniaxial tension, using quantitative polarized light imaging (QPLI) to quantify collagen fiber alignment. After preconditioning, samples were subjected to a stress-relaxation (SR) test followed by quasistatic ramp-to-failure (RF). Peak and equilibrium stress values were computed from the SR test and modulus quantified in the toe- and linear-regions of the RF. QPLI values describing collagen orientation (angle of polarization [AoP]) and strength of alignment (degree of linear polarization [DoLP]) were computed for the SR test and at points corresponding to the zero, transition point, and linear region of the RF. Results: Toe- and linear-region modulus values decreased from region 1 to 6. Slopes of regression lines increased for the average DoLP during RF, with significance at higher strains. The standard deviation of AoP values decreased during RF, indicating tighter distribution of orientation angles, with significant correlations at all points of the RF. During SR, stress values uniformly decreased but did not show significant linear regression by region. DoLP and AoP values changed slightly during SR and demonstrated significant linear variation by region at both peak and equilibrium points. Conclusion: Most microstructural and material properties evaluated in this study appear to follow a linear gradient across the ACL, rather than varying by bundle. Clinical Relevance: This AM-to-PL variation provides a more accurate description of functional tissue anatomy and can be used to assess and guide techniques of ACL reconstruction. [ABSTRACT FROM AUTHOR]

Background: Femoral torsion is a critical parameter in hip and knee disorders. The unproven assumption is that the femoral neck exclusively contributes to the overall torsion of the femur. Purpose/Hypothesis: The aim of this study was to measure femoral torsion at different levels in patients with abnormally high or low femoral torsion and to compare the results with healthy volunteers. Our hypothesis was that the pattern of torsion distribution among the different femoral levels varies between patients with abnormal torsion and healthy volunteers. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Magnetic resonance images of patients with a history of patellar instability and torsion of the femur ≥25° (11 patients, 16 femurs) and ≤0° (14 patients, 22 femurs) were analyzed. Our controls were 30 healthy volunteers (60 femurs). To assess femoral torsion, 4 lines were drawn: a first line through the center of the femoral head and neck, a second line through the center of the femur at the top of the lesser trochanter, a third line tangent to the posterior aspect of the distal femur just above the attachment of the gastrocnemius, and a fourth line tangent to the posterior condyles. Three investigators performed the measurements; 1 performed the measurements twice. Results: All femur segments showed significantly different torsion among the high-torsion, low-torsion, and control groups. Regarding the pattern of torsion distribution, on average, all levels contributed to the torsion. The ratio between the average neck and shaft torsion shifted toward a higher value in the high-torsion group, mostly because of a lack of external torsion in the shaft, and toward a lower value in the low-torsion group, owing to both a lack of internal torsion of the neck and increased external torsion in the shaft. Conclusion: We established a difference between neck, mid, and distal femoral torsion with reproducible measurements. Our data suggest that all 3 levels of the femur contribute to the total femoral torsion, with a different pattern among patients with high torsion and patellar instability. [ABSTRACT FROM AUTHOR]

Background: Medial femoral condyle (MFC) chondral defects cause knee pain. Clinical studies have shown worse functional outcomes and cartilage defect fill rates after microfracture in obese patients (BMI ≥30) and for defects with size ≥2 cm2. Purpose: To determine the effect of obesity, defect size, and cartilage thickness on the force sustained at the base of full-thickness MFC cartilage defects during weightbearing. Study Design: Controlled laboratory study. Methods: Eight human cadaveric knees were loaded in 15° of flexion. A sensor measured force across the medial compartment. The area at the base of the defect protected from load, termed the “area of containment,” was quantified, and loads simulating weightbearing for BMIs of 20, 30, and 40 were applied. A full-thickness cartilage defect was created on the MFC. Cycles of loads were applied for defect sizes with diameters of 6, 8, 10, 12, 14, 16, 18, and 20 mm. A second sensor recorded force at the base of the defect for defects with diameters of 14, 16, 18, and 20 mm. Results: Loads simulating BMI ≥30 led to a decrease in the area of containment for all defects ≥14 mm in diameter (P ≤ .038). Base of defect force increased for defects ≥16 mm in diameter (area, ≥2 cm2) between loaded and unloaded states (P ≤ .042) and for loads simulating BMI ≥30 (P ≤ .045). Cartilage rim thickness <2 mm showed higher base of defect force than did thickness ≥2 mm, for all BMI groups (P ≤ .025). Conclusion: Increased force at the base of MFC cartilage defects was observed for weightbearing loads simulating BMI ≥30, for defect size ≥2 cm2, and for rim thickness <2 mm. This may lead to a biomechanically unfavorable environment after microfracture in these patient subsets. Clinical Relevance: These biomechanical findings corroborate clinical studies that have noted worse outcomes after microfracture in patients with BMI ≥30 and cartilage defects of size ≥2 cm2. Further clinical studies are needed to compare microfracture with other cartilage restoration procedures in these patient subsets. [ABSTRACT FROM AUTHOR]

Background: Stress ultrasound (SUS) of the elbow has demonstrated changes in the anterior band of the ulnar collateral ligament (UCL) in professional baseball pitchers. However, there have been no reports documenting the chronological appearance of these changes. Purpose: To characterize the chronology of anatomic changes of the UCL in a cohort of young professional baseball pitchers. Study Design: Cross-sectional study; Level of evidence, 3. Methods: SUS of the elbow was performed on the dominant arm in 127 asymptomatic professional pitchers aged 17 to 21 years. UCL thickness was measured at rest. The width of the ulnohumeral joint was measured at 30° of elbow flexion, both at rest and with 150 N of valgus stress, using a standardized instrumented device. Any ligament heterogeneity and calcifications were documented. Players were divided into 3 groups based on the number of years of professional experience before the ultrasound examination: 0 years (n = 51), 1-2 years (n = 54), and 3-4 years (n = 22). Additionally, players were divided into 5 groups based on chronological age at the time of the first SUS examination: 17 years (n = 5), 18 years (n = 18), 19 years (n = 33), 20 years (n = 20), and 21 years (n = 51). Statistically significant differences between the groups were determined. Results: The mean UCL thickness was 5.85 ± 1.22 mm, 6.23 ± 1.32 mm, and 6.94 ± 2.12 mm in the players with 0, 1-2, and 3-4 years of professional experience, respectively. This difference was statistically significant overall (P = .024) as well as statistically significant between each consecutive group. There was no statistically significant difference in joint space width at rest or with applied stress between groups (P = .944). Additionally, there was no statistically significant difference in the presence of calcifications (27.5%, 27.8%, and 40.9%, respectively; P = .144) or heterogeneity (29.4%, 16.7%, and 40.9%, respectively; P = .502) as years of professional experience increased from 0 to 3-4 years. There were no significant differences in UCL thickness (P = .363), joint space width with stress (P = .648), or echotextural abnormalities based on chronological age (P = .871 [hypoechoic foci] and P = .520 [calcifications]). Conclusion: These findings suggest that an increase in UCL thickness may be one of the first changes to develop in young professional baseball pitchers. [ABSTRACT FROM AUTHOR]

Background: There have been no clinical studies regarding the effect of decreased meniscal thickness on outcomes after meniscectomy.Purpose: To examine the postoperative outcomes of partial meniscectomy with or without horizontal resection compared with the outcomes of subtotal meniscectomy and to evaluate the influence of decreased thickness of the medial meniscus on out- comes after partial meniscectomy.Study Design: Cohort study; Level of evidence, 3.Methods: A total of 312 patients who underwent medial meniscectomy were retrospectively reviewed. Patients were divided into 3 groups: group A (n = 84) included patients with partial meniscectomy with vertical resection, group B (n = 140) consisted of those with partial meniscectomy with horizontal resection, and group C (n = 88) included those with subtotal meniscectomy. Clin- ical function was evaluated by use of the Lysholm knee scoring scale, International Knee Documentation Committee (IKDC) sub- jective knee evaluation form, and Tapper and Hoover grading system. Radiologic evaluation was performed with the IKDC radiographic assessment scale as well as with measurements of the medial compartment height at the tibiofemoral joint. Preop- erative values and postoperative values measured 5 years after operation were assessed.Results: Functional outcomes in group C were inferior to those in groups A and B according to the Lysholm knee score (mean ± SD for group A = 96.1 ± 4.7, group B = 94.9 ± 5.2, group C = 84.8 ± 11.4; P < .001), IKDC subjective score (group A = 92.1 ± 6.5, group B = 91.3 ± 8.8, group C = 81 ± 11.4; P < .001), and Tapper and Hoover grading system (P = .003). There was no significant difference in scores between groups A and B. With regard to radiologic evaluation, the IKDC radiographic grade for group C was worse than the grades for groups A and B (P < .001); there was no significant difference between groups A and B. However, the postoperative joint space on the affected side was higher for group A (4.7 ± 0.6 mm) than for groups B (4.3 ± 0.5 mm; P < .001) and C (3.7 ± 0.8 mm; P < .001). The joint space was higher in group B than in group C (P < .001).Conclusion: Despite joint space narrowing, decreases in meniscal thickness after partial meniscectomy for horizontal tear had no additional adverse effect on 5-year functional and radiographic outcomes compared with conventional partial meniscectomy pre- serving whole meniscal thickness. In treating horizontal tears of the meniscus, partial meniscectomy with complete resection of the unstable leaf was an effective method in a 5-year follow-up study. [ABSTRACT FROM AUTHOR]

Background: Many clinical and radiographic studies suggest that patient age and sex have an influence on rotator cuff (RC) repair outcomes. However, these findings result from retrospective statistical analyses and cannot provide a causal answer. Purpose: To analyze whether age and sex influence the biological potential at the time of RC repair or midterm clinical and radiographic outcomes. Also assessed was the effect of the biological potential on intraindividual clinical/radiographic results. Study Design: Cohort study; Level of evidence, 2. Methods: A total of 40 patients underwent arthroscopic RC repair. At the time of surgery (t = 0), supraspinatus tendon biopsy specimens were obtained, cultivated, and assessed for their biological potential, particularly (1) cell growth and (2) collagen type I production. After a follow-up at 24 months (t = 1), all patients were assessed by clinical scores (Constant score, subjective shoulder value, American Shoulder and Elbow Surgeons [ASES] score, and Western Ontario Rotator Cuff Index [WORC] score) and underwent magnetic resonance imaging to determine RC integrity. The data were examined for age- and sex-related differences and to identify the correlation between biological potential (t = 0) and clinical/radiographic outcome (t = 1). Results: The follow-up rate for the imaging and clinical evaluation was 100%. Age, but not sex, influenced the biological tendon cell parameters at t = 0. However, there was no effect of age or sex on the clinical and radiographic results at t = 1. Furthermore, no correlation was observed between the initial biological parameters and later clinical outcomes or radiographic RC integrity. Finally, there was no significant difference between intact and nonhealed repairs in terms of the respective clinical scores. Conclusion: Age, but not sex, was found to have a negative effect on RC tendon cell biology. However, neither sex nor, in particular, a higher age influenced repair outcomes after 24 months. [ABSTRACT FROM AUTHOR]

Background: The arthroscopic suture-bridge technique has proved to provide biomechanically firm fixation of the torn rotator cuff to the tuberosity by increasing the footprint contact area and pressure. However, a marginal dog-ear deformity is encountered not infrequently when this technique is used, impeding full restoration of the torn cuff. Purpose: To evaluate the structural and functional outcomes of the use of a modified suture-bridge technique to prevent a marginal dog-ear deformity compared with a conventional suture-bridge method in rotator cuff repair. Study Design: Cohort study; Level of evidence 2. Methods: A consecutive series of 71 patients aged 50 to 65 years who underwent arthroscopic rotator cuff repair for fullthickness medium-sized to massive tears was evaluated. Patients were divided into 2 groups according to repair technique: a conventional suture-bridge technique (34 patients; group A) versus a modified suture-bridge technique to prevent a marginal dog-ear deformity (37 patients; group B). Radiographic evaluations included postoperative cuff integrity using MRI. Functional evaluations included pre- and postoperative range of motion (ROM), pain visual analog scale (VAS), the University of California, Los Angeles (UCLA) shoulder rating scale, the Constant score, and the American Shoulder and Elbow Surgeons (ASES) score. All patients were followed up clinically at a minimum of 1 year. Result: When the 2 surgical techniques were compared, postoperative structural integrity by Sugaya classification showed the distribution of types I:II:III:IV:V to be 4:20:2:4:4 in group A and 20:12:4:0:1 in group B. More subjects in group B had a favorable Sugaya type compared with group A (P<.001). The postoperative healed:retear rate was 26:8 in group A and 36:1 in group B, with a significantly lower retear rate in group B (P = .011). However, there were no significant differences in ROM and all functional outcome scores between the 2 groups postoperatively. When surgical techniques were compared across healed (n = 62) and retear (n = 9) groups, significantly fewer modified suture-bridge technique repairs were found in the retear group (P = .03). There were significant differences between healed and retear groups in functional outcome scores, with worse results in the retear group. Conclusion: A modified suture-bridge technique to prevent a marginal dog-ear deformity provided better structural outcomes than a conventional suture-bridge technique for medium-sized to massive rotator cuff tears. This technique may ultimately provide better functional outcomes by decreasing the retear rate. [ABSTRACT FROM AUTHOR]

The article focuses on the impact of knee flexion angle, rotational torque and anterior/posterior translational force on end-to-end distance between femoral and tibial insertion sites of posterior cruciate ligament (PCL). Topics discussed include the anatomy of PCL including its four functional bundles on the basis of structure and function, the results of the authors' study including change in the end-to-end distance of PCL in range of motion and that with internal/external rotational torque.

Meniscal root tears, less common than meniscal body tears and frequently unrecognized, are a subset of meniscal injuries that often result in significant knee joint disorders. The meniscus root attachment aids meniscal function by securing the meniscus in place and allowing for optimal shock-absorbing function in the knee. With root tears, meniscal extrusion often occurs, and the transmission of circumferential hoop stresses is impaired. This alters knee biomechanics and kinematics and significantly increases tibiofemoral contact pressure. In recent years, meniscal root tears, which by definition include direct avulsions off the tibial plateau or radial tears adjacent to the root itself, have attracted attention because of concerns that significant meniscal extrusion dramatically inhibits normal meniscal function, leading to a condition biomechanically similar to a total meniscectomy. Recent literature has highlighted the importance of early diagnosis and treatment; fortunately, these processes have been vastly improved by advances in magnetic resonance imaging and arthroscopy. This article presents a review of the clinically relevant anatomic, biomechanical, and functional descriptions of the meniscus root attachments, as well as current strategies for accurate diagnosis and treatment of common injuries to these meniscus root attachments. [ABSTRACT FROM PUBLISHER]

The article presents research which examined the age-related differences in cells derived from the anterior cruciate ligament (ACL). Topics covered include the description of ACL tissues in adolescent and younger patients as well as collection of ACL remnants from 28 patients. Also mentioned is the need for surgeons to consider the age of patients when assessing healing potential of those with ACL injuries.

The article discusses a study that evaluated the impact of aging on tendon-to-bone healing in an established rat model of rotator cuff repair. The aged animal colony from the National Institute on Aging of the National Institutes of Health was used. Histologic portions of the tendon-to-bone interface were examined with hematoxylin and eosin staining. Old animals showed diminished tendon-to-bone healing after rotator cuff injury and repair in a rat model of aging.

The article provides a review on the diagnosis and management of instability and degenerative arthritis of the sternoclavicular joint. A database search from PubMed search engine using terms like sternoclavicular instability and arthritis was done in August 2012. A figure-of-8 graft reconstruction is suggested as method based on biomechanical data and clinical series. Indications for surgical management include failed closed reduction or chronic recurrence of posterior dislocations.

The article presents a study that evaluates the incidence of roof impingement by the native anterior cruciate ligament (ACL) in hyperextensible knees. The study examines the risk of roof impingement by anatomic placement of the ACL graft in hyperextensible knees. It urges surgeons to consider roof impingement after anatomic double-bundle ACLreconstruction in patients with a hyperextensible knee.

The article presents a study that determines the primary biomechanical function of the isolated posteromedial bundle, anterolateral bundle, and the intact posterior cruciate ligament (PCL) between 0° and 120°of knee flexion. The study explores the role of PCL's functional bundles through the full range of knee flexion. It suggests a codominant relationship between the two bundles based on their ability to resist posterior tibial translation.

Osteoarthritis of the acromioclavicular (AC) joint is a common condition causing anterior or superior shoulder pain, especially with overhead and cross-body activities. This most commonly occurs in middle-aged individuals because of degeneration to the fibrocartilaginous disk that cushions the articulations. Diagnosis relies on history, physical examination, imaging, and diagnostic local anesthetic injection. Diagnosis can be challenging given the lack of specificity with positive physical examination findings and the variable nature of AC joint pain. Of note, symptomatic AC osteoarthritis must be differentiated from instability and subtle instability, which may have similar symptoms. Although plain radiographs can reveal degeneration, diagnosis cannot be based on this alone because similar radiographic findings can be seen in asymptomatic individuals. Nonoperative therapy can provide symptomatic relief, whereas patients with persistent symptoms can be considered for resection arthroplasty by open or arthroscopic technique. Both techniques have proven to provide predictable pain relief; however, each has its own unique set of potential complications that may be minimized with an improved understanding of the anatomical and biomechanical characteristics of the joint along with meticulous surgical technique. [ABSTRACT FROM PUBLISHER]

Background: Morphological alterations of the hip joint are important contributors to the development of osteoarthritis. Whileplane-specific variations in the shape of the proximal femur have been described, there are no defined reference standardsfor measurements in adolescent patients.Purpose: To evaluate hips in asymptomatic adolescent patients using radially reformatted multidetector computed tomography(MDCT) to define the morphological characteristics of the femoral head-neck (FHN) junction with respect to patient sex and physealstatus, and to establish reference values for a angle, FHN offset, and epiphyseal extension (EE).Study Design: Cross-sectional study; Level of evidence, 3.Methods: A total of 132 pelvic MDCT scans in adolescent patients with abdominal pain were reformatted into radially orientedplanes along the femoral necks. The diameter of the femoral head, a angle, EE, and FHN offset were measured. Reference valuesfor a angle, EE, and FHN offset were determined, and the α angle, EE, and FHN offset were compared between open versusclosed physeal status for each sex.Results: The α angle measurements in male patients were higher than in female patients in anterior (A), anterosuperior (AS), andsuperior (S) planes (P < .001). The median α angle was highest for all patients in the AS plane (male, 52°; female, 49°). Openphyses correlated with higher α angles compared with closed physes in all imaging planes except the AS plane. The FHN offsetwas lowest in the AS plane for all patients and was increased in female patients with closed physes compared with open physesin the A plane and in the A, S, posterosuperior, and posterior planes in male patients (P<.05). There were subtle plane-specificvariations in EE.Conclusion: The a angle is higher and FHN offset is lower in the AS plane in patients with closed versus open physes, whereasthe opposite is true in all other planes. The a angles in male patients were higher than in female patients, although there were nosignificant sex-based differences in the FHN offset. The a angles were highest and FHN offset was lowest in the AS plane. Therewere subtle variations in EE across all planes, and the EE was higher in patients with closed versus open physes.Clinical Relevance: Plane- and sex-specific reference values for a angle, FHN offset, and EE in asymptomatic adolescent patientswill assist orthopaedic surgeons and radiologists in appropriately suggesting femoroacetabular impingement based onthe imaging evaluation of patients with hip pain, whose measurements lie at the periphery of or outside the reference intervalsin the appropriate clinical context. [ABSTRACT FROM AUTHOR]

Background: There has been no study using magnetic resonance arthrography (MRA) to compare clinical features and structuralintegrity after arthroscopic repair of bursal and articular side partial-thickness rotator cuff tears (PTRCTs).Hypothesis: The 2 groups studied, which consisted of patients who underwent arthroscopic repair for either the articular side orthe bursal side, would show significant improvement in overall outcomes after surgery, even though clinical outcomes and structuralintegrity would not be significantly different. It was thought that the incidence of preoperative positive impingement signs andprotruded spurs on the acromion undersurface would be higher in patients with a bursal side tear.Study Design: Case-control study; Level of evidence, 3.Methods: The current study consisted of 83 patients who underwent arthroscopic repair for either articular side (group A; n = 29)or bursal side (group B; n = 54) PTRCT and who were available at the 2-year follow-up. Clinical outcomes were compared by useof the Neer impingement sign, visual analog scale for pain, Simple Shoulder Test, University of California Los Angeles score, andAmerican Shoulder and Elbow Surgeons score. At 6 months after surgery, MRA was used to assess structural integrity.Results: At 2-year follow-up, both groups showed significant improvement in pain and shoulder function scores, even thoughthere was no significant difference between groups. The retear rate on follow-up MRA was not significantly different betweengroup A (8%) and B (11%). Patients in group B, compared with group A, showed a higher incidence of the preoperative impingementsign (89% vs 52%, respectively; P = .004), protruded spur on the acromion undersurface (69% vs 0%, respectively; P<.001), and concomitant acromioplasty (93% vs 24%, respectively; P<.001).Conclusion: Both articular and bursal side PTRCTs showed significant functional improvements after arthroscopic repair. Thebursal side tears had a higher incidence of impingement sign at preoperative examination and more often had a protrudedspur on the acromion undersurface. [ABSTRACT FROM AUTHOR]

The article presents a cross-sectional study which was carried out to use quantitative magnetic resonance imaging (MRI) to examine the patellar cartilage in patients with patellofemoral pain. It mentions that 20 patients in the age group of 18 to 45 years with anterior knee pain and no evidence of osteoarthrities were employed for the study. It concludes that lateral facets of patients with patellofemoral pain (PFP) and patellar tilt were not seen in control patients.

The article focuses on a controlled study conducted to understand the impact of bioenhanced anterior constructive ligament (ACL) repair by a bioactive scaffold. The study was conducted on 64 pigs. The results showed that structural properties of tendons after bioenhanced ACL repair were not significantly different from those in bioenhanced ACL reconstruction or conventional ACL but significantly better then untreated ACL transection. The posttraumatic osteoarthritis was also reduced.

The article discusses a cartilage status in relation to return to sports after anterior cruciate ligament (ACL) reconstruction. The article provides various results and high impacts on the qualitatively diminished cartilage that might play a role in the development of osteoarthritis in ACL reconstruction was concluded. The article concludes that high impacts on this qualitatively diminished cartilage might play a role in the development of osteo-arthritis in ACL reconstruction.

The article discusses Magnetic resonance imaging (MRI) which is a noninvasive technology that can quantitatively assess anterior cruciate ligament (ACL) graft size and signal intensity. The study provides various hypothesis and discusses method. It gives various results and volume and grayscale values from high-resolution T2 weighted MRI scans are predictive of structural properties of the healing ligament or graft in a porcine was concluded.

The article discusses the correlation of tibial footprint of the anterior cruciate ligament (ACL) with the intercondylar roof in anatomic ACL reconstructions. It states that there is no statistical relationship between the intercondylar roof angle and the location of the native footprint of the ACL on the tibia. It also discusses various methods and gives relationship of ACL Footprint and Intercondylar Roof Angle.

Background: Currently, osteochondral allografts (OCA) are typically used after 4°C storage for prolonged durations (15-43 days), which compromises chondrocyte viability, especially at the articular surface. The long-term in vivo performance of these fresh-stored allografts, in association with variable cellularity, is unknown. Purpose: To determine the effect of 4°C storage duration (14, 28 days) versus the best (fresh) and worst (frozen) conditions of chondrocyte viability on structure, composition, and function of cartilage in the goat and the association of retrieved chondrocyte cellularity with those tissue properties. Study Design: Controlled laboratory study. Methods: The effect of allograft storage on in vivo repair outcomes was determined for OCA transplanted into 15 recipient goats and analyzed at 12 months. Repair outcomes were assessed by examining cartilage structure (gross, histopathology), composition (cellularity by depth, matrix fixed charge), and biomechanical function (stiffness). Relationships between cellularity and structural scores, matrix fixed charge, and stiffness were assessed by linear regression. Results: Repair outcomes in 4°C-stored OCA were similar after 14 and 28 days of storage, and both were inferior to fresh OCA and were accompanied by diminished cellularity at the surface, matrix fixed charge, and histopathological structure. Overall, cellularity by depth and matrix fixed charge in cartilage of fresh OCA were similar to nonoperated controls. However, cellularity at the articular surface and matrix fixed charge in 4°C-stored OCA were lower than fresh, by ~55% (95% confidence interval [CI], 32%-76%) and ~20% (CI, 9%-30%), respectively. In frozen OCA, cellularity and matrix fixed charge were lower than 4°C-stored OCA, by ~93% (CI, 88%-99%) and ~22% (CI, 10%-35%), respectively. Cellularity correlated negatively with cartilage health indices, including structural scores, and positively with matrix fixed charge and stiffness. Conclusion: Reduced cellularity at the articular surface, resulting from 4°C storage, was associated with variable long-term outcomes versus consistently good repair by fresh allografts. Cellularity at the articular surface was an important index of biological performance. Clinical Relevance: Normal chondrocyte density in vivo, especially in the superficial region of cartilage, is important for maintaining long-term cartilage function and matrix content. In human cartilage, containing cells at ~3 to 5 times lower density than goat, repair outcomes may be related to absolute minimum number of cells rather than density. [ABSTRACT FROM AUTHOR]

The optimal treatment of posterior cruciate ligament ruptures remains controversial despite numerous recent basic science advances on the topic. The current literature on the anatomy, biomechanics, and clinical outcomes of posterior cruciate ligament reconstruction is reviewed. Recent studies have quantified the anatomic location and biomechanical contribution of each of the 2 posterior cruciate ligament bundles on tunnel placement and knee kinematics during reconstruction. Additional laboratory and cadaveric studies have suggested double-bundle reconstructions of the posterior cruciate ligament may better restore normal knee kinematics than single-bundle reconstructions although clinical outcomes have not revealed such a difference. Tibial inlay posterior cruciate ligament reconstructions (either open or arthroscopic) are preferred by many authors to avoid the “killer turn” and graft laxity with cyclic loading. Posterior cruciate ligament reconstruction improves subjective patient outcomes and return to sport although stability and knee kinematics may not return to normal. [ABSTRACT FROM PUBLISHER]

Background: Current surgical treatments for acromioclavicular separations do not re-create the anatomy of the acromioclavicular joint. Hypothesis: Anatomical acromioclavicular reconstruction re-creates the strength of the native acromioclavicular joint and is stronger than a modified Weaver-Dunn repair. Study Design: Controlled laboratory study. Methods: The native acromioclavicular joint in 6 fresh-frozen cadaveric upper extremities was stressed to failure under uniaxial tension in the coronal plane. A modified Weaver-Dunn procedure, anatomical acromioclavicular reconstruction using a palmaris longus graft, and anatomical acromioclavicular reconstruction using a flexor carpi radialis graft were then performed sequentially. Each repair was stressed to failure. Load-displacement curves and mechanism of failure were recorded for each. Results: Loads at failure for the native acromioclavicular joint complex, modified Weaver-Dunn procedure, anatomical acromioclavicular reconstruction using a palmaris longus tendon graft, and anatomical acromioclavicular reconstruction using a flexor carpi radialis tendon graft were 815 N, 483 N, 326 N, and 774 N, respectively. The strength of the native acromioclavicular joint complex was significantly different from the modified Weaver-Dunn repair (P < .001) and the anatomical acromioclavicular reconstruction using a palmaris longus tendon graft (P < .001) but not from the anatomical acromioclavicular reconstruction using a flexor carpi radialis tendon graft (P = .607). Conclusion: The strength of the described anatomical acromioclavicular reconstruction is limited by the tendon graft used. Anatomical acromioclavicular reconstruction with a flexor carpi radialis tendon graft re-creates the tensile strength of the native acromioclavicular joint complex and is superior to a modified Weaver-Dunn repair. [ABSTRACT FROM AUTHOR]

Background: Variations in ankle mortise anatomy may be a predisposing factor to ankle instability. Hypothesis: A posteriorly positioned fibula associated with ankle instability may not be a true pathologic entity but rather the result of measuring off an internally rotated talus. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: The authors reviewed 60 ankle computed tomography scans performed on patients from their institution for reasons unrelated to ankle instability. They also reviewed ankle computed tomography scans on 21 patients surgically treated for clini- cal ankle instability. The position of the fibula in relation to the talar articular surface was calculated and expressed as the axial malleolar index, as described by Scranton et al. They also calculated the intermalleolar index, a new method that references the medial malleolus, not the talus. Results: Using the method of Scranton et al, the axial malleolar index in the control and instability patients was similar to val- ues previously described, and there was a significant difference between control and instability patients (Pc .01). However, using the intermalleolar index method referencing the medial malleolus, there was not a significant difference between control and instability patients (P = .43). Conclusion: The new method of referencing the medial malleolus assesses fibular position independent of talar rotation. The data, when referencing the medial malleolus, do not show significant variation in fibular position in patients with and without ankle instability. [ABSTRACT FROM AUTHOR]

The advent of shoulder arthroscopy, as well as our improved understanding of shoulder anatomy and biomechanics, has led to the identification of previously undiagnosed lesions involving the superior labrum and biceps tendon anchor. Although the history and physical examination, as well as improved imaging modalities such as magnetic resonance arthrography, are extremely important in understanding the abnormalities, the definitive diagnosis of superior labrum, anterior and posterior lesions is best made through diagnostic arthroscopy. Treatment of these lesions is directed according to its type. In general, type I and III lesions are debrided, whereas type II and many type IV lesions are repaired. The purpose of this article is to review the anatomy, biomechanics, classification, diagnosis, and current treatment recommendations for these lesions, as well as to review the literature. [ABSTRACT FROM AUTHOR]