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Background: Lateral meniscal deficiency with valgus malalignment increases the rate of lateral compartment osteoarthritis. Lateral meniscal allograft transplantation (LMAT) with a concomitant varus-producing opening-wedge distal femoral osteotomy (DFO) is an option yet to be evaluated biomechanically., Purpose/hypothesis: The purpose of this study was to clarify the biomechanical effects of the realignment procedure in the setting of LMAT. We hypothesized that (1) given the dependence of the lateral compartment on the lateral meniscus, a DFO and increasing degrees of varus would be insufficient to restore lateral compartment pressures to normal from a lateral meniscus-deficient state, and that (2) LMAT would restore lateral compartment pressures to the intact state while DFO would decrease lateral compartment pressures for any given state of the meniscus., Study Design: Controlled laboratory study., Methods: Ten cadaveric knees underwent opening-wedge varus-producing DFO secured by an external fixator. Anatomic alignment was standardized to 6° of mechanical valgus, and each joint was tested in full extension. Submeniscal placement of thin film pressure sensors allowed for the recording of contact pressure, peak contact pressure, and contact area. The specimens were loaded on a biaxial dynamic testing machine with loading angles between 9° valgus and 6° varus of mechanical alignment. Conditions tested included intact meniscus, meniscal deficiency, and meniscal transplantation., Results: Isolated varus-producing DFO to 6° in the meniscus-deficient state failed to restore joint pressures and contact areas to the intact state, with significant changes in mean contact pressure (175%), mean peak contact pressure (135%), and contact area (-41%) (all P < .05 vs intact), while LMAT restored all outcome measures (all P > .05 compared with intact). After LMAT, every additional 1° of DFO correction contributed to a decrease in the mean contact pressure, peak pressure, and contact area of 5.6% (-0.0479 N/mm 2 ), 5.9% (-0.154 N/mm 2 ), and 1.4% (-6.99 mm 2 ) for the lateral compartment and 7.3% (+0.034 N/mm 2 ), 12.6% (+0.160 N/mm 2 ), and 4.3% (+20.53 mm 2 ) for the medial compartment, respectively., Conclusion: Isolated DFO was inadequate to restore load distribution in meniscus-deficient knees, while concomitant LMAT restored near normal forces and improved the lateral compartment biomechanical profile., Clinical Relevance: Our findings support the concomitant use of LMAT and varus-producing DFO in the setting of lateral meniscal deficiency with valgus malalignment. This study provides tools for the orthopaedic surgeon to individualize the correction for each patient., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: S.L. has received grant support from Arthrex; education payments from Arthrex and Smith & Nephew; and hospitality payments from Medical Device Business Services. R.M.F. has received education payments from Arthrex and Smith & Nephew; consulting fees and nonconsulting fees from Arthrex; and hospitality payments from JRF Ortho. A.F.V. has received consulting fees from Arthrex and Stryker; speaking fees from Arthrex and Smith & Nephew; and honoraria from Vericel. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2023.)

Background: The most reliable suture technique for capsular closure after a capsulotomy remains unknown., Purpose: To determine which suture technique best restores native stability after a 5-cm interportal capsulotomy., Study Design: Controlled laboratory study., Methods: Ten human cadaveric hip specimens were tested using a 6-degrees-of-freedom robotic arm in 7 states: intact, capsular laxity, 5-cm capsulotomy, standard suture, shoelace, double shoelace, and Quebec City slider (QCS). Rotational range of motion (ROM) was measured across 9 tests: flexion, extension, abduction, abduction at 45° of flexion, adduction, external rotation, internal rotation, anterior impingement, and log roll. Distraction (ie, femoral head translation [FHT]) was measured across a range of flexion and abduction angles., Results: When compared with the native state, the 5-cm capsulotomy state showed the largest laxity increases on all tests, specifically in external rotation ROM (+13.4°), extension ROM (+11.5°), and distraction FHT (+4.5 mm) ( P < .001 for all). The standard suture technique was not significantly different from the 5-cm capsulotomy on any test and demonstrated significantly more flexion ROM than the double shoelace suture (+1.41°; P = .049) and more extension ROM (+5.51°; P = .014) and external rotation ROM (+6.03°; P = .021) than the QCS. The standard suture also resulted in significantly higher distraction FHT as compared with the shoelace suture (+1.0 mm; P = .005), double shoelace suture (+1.4 mm; P < .001), and QCS (+1.1 mm; P = .003). The shoelace, double shoelace, and QCS techniques significantly reduced hip laxity when compared with the 5-cm capsulotomy state, specifically in external rotation ROM (respectively, -8.1°, -7.8°, and -10.2°), extension ROM (-6.3°, -7.3°, and -8.1°), and distraction FHT (-1.8, -2.2, and -1.9 mm) ( P ≤ .003 for all). These 3 techniques restored native stability (no significant difference from intact) on some but not all tests, and no significant differences were observed among them on any test., Conclusion: Hip capsule closure with the standard suture technique did not prevent postoperative hip instability after a 5-cm capsulotomy, and 3 suture techniques were found to be preferable; however, none perfectly restored native stability at time zero., Clinical Relevance: The shoelace, double shoelace, and QCS suture techniques are recommended when closing the hip capsule., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: S.U. has received research support from Smith & Nephew and consulting fees from ConMed and Smith & Nephew. M.J.P. has received research support from Ossur, Siemens, Smith & Nephew, and Vail Valley Medical Center; consulting fees from Smith & Nephew; speaking fees from Synthes; and royalties from Arthrosurface, Bledsoe, ConMed Linvatec, DJO, and Smith & Nephew. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2022.)

Background: The prevalence of findings on shoulder magnetic resonance imaging (MRI) is high in asymptomatic athletes of overhead sports., Purpose/hypothesis: The purpose of this study was to determine the prevalence of atypical findings on MRI in shoulders of asymptomatic, elite-level climbers and to evaluate the association of these findings with clinical examination results. It was hypothesized that glenoid labrum, long head of the biceps tendon, and articular cartilage pathology would be present in >50% of asymptomatic athletes., Study Design: Cross-sectional study; Level of evidence, 3., Methods: A total of 50 elite climbers (age range, 20-60 years) without any symptoms of shoulder pain underwent bilateral shoulder examinations in addition to dedicated bilateral shoulder 3-T † MRI. Physical examinations were performed by orthopaedic sports medicine surgeons, while MRI scans were interpreted by 2 blinded board-certified radiologists to determine the prevalence of abnormalities of the articular cartilage, glenoid labrum, biceps tendon, rotator cuff, and acromioclavicular joint., Results: MRI evidence of tendinosis of the rotator cuff, subacromial bursitis, and long head of the biceps tendonitis was exceptionally common, at 80%, 79%, and 73%, respectively. Labral pathology was present in 69% of shoulders, with discrete labral tears identified in 56%. Articular cartilage changes were also common, with humeral pathology present in 57% of shoulders and glenoid pathology in 19% of shoulders. Climbers with labral tears identified in this study had significantly increased forward elevation compared with those without labral tears in both active ( P = .026) and passive ( P = .022) motion., Conclusion: The overall prevalence of intra-articular shoulder pathology detected by MRI in asymptomatic climbers was 80%, with 57% demonstrating varying degrees of glenohumeral articular cartilage damage. This high rate of arthritis differs significantly from prior published reports of other overhead sports athletes., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: M.N.S. has received education payments from Southern Edge Orthopaedics. C.P.H. has received consulting fees from Smith & Nephew. T.R.H. has received hospitality payments from Arthrex. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2022.)

Background: The treatment for borderline developmental dysplasia of the hip (BDDH) has historically been arthroscopic surgery or periacetabular osteotomy (PAO). As orthopaedic surgery is constantly evolving, a lack of comparison of outcomes for these 2 treatment methods could potentially be stalling the progression of treatment for patients with BDDH., Purpose: To evaluate the existing literature on patient characteristics, procedures, clinical outcomes, and failure rates for patients with BDDH and to determine whether PAO or hip arthroscopic surgery is a better treatment method for patients with BDDH., Study Design: Systematic review; Level of evidence, 4., Methods: Studies included were found using the following search words: "hip" and "borderline dysplasia," "osteotomy" or "arthroscopy," and "outcome" or "procedure." Articles were included if they detailed participants of all sexes and ages, reported on isolated hips, and had patients diagnosed with BDDH., Results: A search was conducted across 3 databases, resulting in 469 articles for consideration, from which 12 total studies (10 on arthroscopic surgery and 2 on PAO) were chosen for a review. There were 6 studies that included patients with a lateral center-edge angle of 18° to 25°, while the remainder included patients with a lateral center-edge angle of 20° to 25°. All the studies reviewing arthroscopic surgery reported concomitant/accessory procedures, while the articles on the topic of PAO did not. It was determined that, whether treated using arthroscopic surgery or PAO, outcomes improved across all patient-reported outcome measures. Revision surgery was also common in both procedures., Conclusion: There is a lack of consensus in the literature on the best treatment option for patients with BDDH. Preoperative patient characteristics and concomitant injuries should be considered when evaluating which surgical procedure will result in the most favorable outcomes., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: M.J.P. has received educational support from Linvatec; speaking fees and consulting fees from Smith & Nephew; royalties from DJO, Linvatec, and Smith & Nephew; and hospitality payments from Siemens. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2021.)

Background: Satisfactory outcomes have been reported after all-inside meniscus ramp repair with combined anterior cruciate ligament reconstruction (ACLR). However, clinical outcomes after ACLR with inside-out meniscus ramp repair are limited., Purpose/hypothesis: The purpose of this study was to evaluate patient-reported outcomes for patients who underwent ACLR and medial meniscus ramp repair compared with those who underwent isolated ACLR; patients in the 2 groups were matched for age, sex, and sport/activity. The null hypothesis was that there would be no significant differences in clinical outcomes between groups at a minimum of 2 years postoperatively., Study Design: Cohort study; Level of evidence 3., Methods: Patients who underwent primary ACLR with bone-patellar tendon-bone (BPTB) autograft by a single surgeon were retrospectively identified. A subgroup of patients with combined ACLR and meniscus ramp repair with a minimum 2-year postoperative follow-up were matched to a cohort who underwent isolated ACLR. Subjective patient-reported questionnaires, knee stability, and return to level of activity/sport were collected., Results: There were 851 patients who underwent primary ACLR; of these, 158 (18.6%) had medial meniscus ramp lesions confirmed at arthroscopy. The most common clinical characteristics in patients with ramp lesions were chronic injuries (68.4%), contact mechanism (88%), concomitant lateral meniscus tears (63.2%), and concomitant lateral meniscus posterior root tears (22.2%). Further, 50 patients who underwent combined ACLR and meniscus ramp repair with minimum 2-year follow-up were matched to patients who underwent isolated ACLR. Both groups reported significant improvements in subjective outcomes from preoperative to postoperative assessments ( P < .001). No significant differences were found in postoperative outcomes for combined ACLR with ramp repair versus isolated ACLR ( P > .05). Patients with meniscus ramp repair had increased preoperative knee laxity demonstrated by grade 3 Lachman (44% vs 6%) and pivot-shift (38% vs 12%) test results compared with patients who underwent isolated ACLR ( P ≤ .005 for both)., Conclusion: This study demonstrates similar clinical outcomes, knee stability on postoperative physical examination, and return-to-sport rates for patients who underwent combined ACLR with BPTB autograft and inside-out meniscus ramp repair versus a matched cohort who underwent isolated ACLR. Clinicians should have a high index of suspicion for the presence of ramp lesions in patients with ACL tears who have a contact mechanism of injury, grade 3 Lachman test result, and concomitant lateral meniscal abnormality., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: T.J.D. has received educational support from Smith & Nephew. L.E. has received research support from Arthrex, Biomet, Health Southeast Norway, and Smith & Nephew and royalties from Arthrex and Smith & Nephew, and he has stock/stock options in iBalance. R.F.L. has received educational support from Arthrex, consulting fees from Arthrex and Smith & Nephew, speaking fees from Smith & Nephew, and royalties from Arthrex. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2020.)

Background: Subpectoral biceps tenodesis can be performed with cortical fixation using different repair techniques. The goal of this technique is to obtain a strong and stable reduction of biceps tendon in an anatomic position., Purpose/hypothesis: The purpose of this study was to compare (1) displacement during cyclic loading, (2) ultimate load, (3) construct stiffness, and (4) failure mode of the biceps tenodesis fixation methods using onlay techniques with an all-suture anchor versus an intramedullary unicortical button. It was hypothesized that fixation with all-suture anchors using a Krackow stitch would exhibit biomechanical characteristics similar to those exhibited by fixation with unicortical buttons., Study Design: Controlled laboratory study., Methods: Ten pairs of fresh-frozen cadaveric shoulders (N = 20) were dissected to the humerus, leaving the biceps tendon-muscle unit intact for testing. A standardized subpectoral biceps cortical (onlay) tenodesis was performed using either an all-suture anchor or a unicortical button. The biceps tendon was initially cycled from 5 to 70 N at a frequency of 1.5 Hz. The force on the tendon was then returned to 5 N, and the tendon was pulled until ultimate failure of the construct. Displacement during cyclic loading, ultimate failure load, stiffness, and failure modes were assessed., Results: Cyclic loading resulted in a mean displacement of 12.5 ± 2.5 mm for all-suture anchor fixation and 29.2 ± 9.4 mm for unicortical button fixation ( P = .005). One all-suture anchor fixation and 2 unicortical button fixations failed during cyclic loading. The mean ultimate failure load was 170.4 ± 68.8 N for the all-suture anchor group and 125.4 ± 44.6 N for the unicortical button group ( P = .074), with stiffness 59.3 ± 11.6 N/mm and 48.6 ± 6.8 N/mm ( P = .091), respectively. For the unicortical button, failure occurred by suture tearing through tendon in 100% of the specimens. For the all-suture anchor, failure occurred by suture tearing through tendon in 56% and knot failure in 44% of the specimens., Conclusion: The all-suture anchor fixation using a Krackow stitch for subpectoral biceps tenodesis provided ultimate load and stiffness similar to unicortical button fixation using a nonlocking whipstitch. The all-suture anchor fixation technique was shown to be superior in terms of displacement during cyclic loading when compared with the unicortical button fixation technique. However, the results of this study help to show that the fixation method used on the humeral side is less implicative of the overall construct strength than stitch location and technique, as the biceps tendon tissue and stitch configuration seem to be the limiting factor in subpectoral onlay tenodesis techniques., Clinical Relevance: All-suture anchors have a smaller diameter than traditional suture anchors, can be inserted through curved guides, and preserve humeral bone stock without compromising postoperative imaging. This study supports use of the all-suture anchor fixation technique for subpectoral biceps tenodesis, with high biomechanical fixation strength and low displacement, as an alternative to the subpectoral onlay biceps tenodesis technique., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported with materials from Arthrex. This research was supported by the Steadman Philippon Research Institute (SPRI), which is a 50l(c)(3) nonprofit institution supported financially by private donations and corporate support. During the past calendar year, SPRI has received grant funding or in-kind donations from Arthrex, DJO, MLB, Ossur, Siemens, Smith & Nephew, and XTRE. This work was partially supported by materials from Arthrex. P.J.M. has received research support from Arthrex, Ossur, Siemens, and Smith & Nephew; consulting fees from Arthrex; and royalties from Arthrex and MedBridge; and owns stock in VuMedi with stock options in Game Ready. L.L.’s position at SPRI was funded by AGA, which is supported by Arthrex. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2019.)

Background: There is significant discrepancy in the reported vascularity within the meniscus, and a progressively diminishing blood supply may indicate a differential healing capacity of tears that is dependent on the affected meniscal zone., Purpose: To examine the outcomes after inside-out meniscal repair in all 3 meniscal vascularity zones., Study Design: Cohort study; Level of evidence, 3., Methods: Patients were included if they underwent inside-out meniscal repair by a single surgeon between 2010 and 2014 and had a minimum 2-year follow-up. Patients were divided into 3 groups based on the meniscal tear location (red-red, red-white, and white-white zones) as determined during an intraoperative assessment. Patient-reported outcome scores were obtained at final follow-up., Results: A total of 173 patients (mean age, 33.6 ± 14.3 years) were included, with a mean follow-up of 2.9 ± 0.9 years. All patients demonstrated significant improvements with inside-out meniscal repair from preoperatively to postoperatively, regardless of the meniscal tear location. Patients who underwent meniscal repair in the red-red and red-white zones had significantly increased postoperative Tegner, Lysholm, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores compared with patients who underwent meniscal repair in the white-white zone ( P < .05). Patients who underwent acute repair (≤6 weeks) demonstrated significantly higher improvements on the Tegner activity scale (acute: 5.8 ± 2.2; chronic: 4.6 ± 2.2; P = .001) and Lysholm score (acute: 85.6 ± 13.3; chronic: 80.8 ± 13.5; P = .025) compared with patients treated beyond 6 weeks from injury, regardless of the meniscal tear zone. Patients with grade IV femoral condyle chondral lesions at the time of surgery had significantly inferior outcomes compared with patients with grade I through III chondral lesions, regardless of the meniscal tear zone. Three patients (1.7%) subsequently underwent revision inside-out repair, and 3 (1.7%) underwent partial meniscectomy., Conclusion: Patients who underwent inside-out meniscal repair demonstrated significant improvements on subjective outcome measures at a minimum 2-year follow-up, regardless of the meniscal tear zone. Inside-out meniscal repair is recommended for potentially reparable meniscal tears in all 3 vascular zones; however, improved outcomes can be achieved when performed acutely, in the absence of full-thickness femoral condyle chondral injuries, and in the red-red and red-white zones., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: R.F.L. is a consultant for and receives royalties from Arthrex, Ossur, and Smith & Nephew. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: High recurrence rates have been reported after anterior shoulder dislocations, regardless of the treatment utilized. However, the definition of recurrent instability has been inconsistent, making a comparison between studies difficult., Purpose: To report on the nature with which the rate of recurrent instability is reported after arthroscopic Bankart repair, across all levels of evidence, and to analyze factors that may affect the reported rate of recurrence., Study Design: Systematic review; Level of evidence, 4., Methods: A systematic review of the literature was performed by searching PubMed, the Cochrane Central Register of Controlled Trials, Embase, and ClinicalTrials.gov for studies published within the dates of January 2008 and September 2018. Studies in English that reported on the recurrence of instability after arthroscopic Bankart repair for anterior shoulder instability were considered for inclusion in this review. A meta-regression was performed to test for a linear association between the reported recurrence rate and several continuous covariates, including mean age at surgery, mean length of follow-up, attrition rate (loss to follow-up percentage), and percentage of male patients., Results: A trim-and-fill meta-analysis yielded an estimated overall recurrence rate of 17.4% (95% CI, 14.3%-20.9%). There was a significant difference in the recurrence rate depending on the level of evidence (Q(3) = 10.98; P = .012). Significant associations were found with the recurrence rate through the meta-regression, including a negative association with mean age ( P = .009), a positive association with mean follow-up time ( P = .002), and a positive association with attrition rate ( P = .035)., Conclusion: A call for standardization is necessary for reporting outcomes of anterior instability after arthroscopic Bankart repair, especially with regard to the reporting of recurrence/failure rates, with careful consideration of the effects that may occur from patient demographics and study design. With no current recommendations for deeming failure, we suggest that all forms of instability be accounted for when determining a failed treatment procedure, with future studies placing an emphasis on greater control of the study design., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: R.F.L. has received consulting fees, speaking fees, and royalties from Smith & Nephew and educational support, consulting fees, speaking fees, and royalties from Arthrex. M.T.P. has received honoraria from Arthrosurface and hospitality payments from Smith & Nephew. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: Imaging of the femoral trochlea has been inherently difficult because of its convex anatomy., Purpose/hypothesis: The purpose of this study was to compare the diagnostic utility of a standard axial magnetic resonance imaging (MRI) sequence with an axial-oblique MRI sequence of the knee for the detection of trochlear articular cartilage lesions on a high-field 3-T MRI scanner. We hypothesized that axial-oblique MRI scans of the knee obtained along the true axis of the trochlea would significantly improve the detection of high-grade cartilage lesions., Study Design: Cohort study (diagnosis); Level of evidence, 2., Methods: Patients who underwent MRI and subsequent surgery for any indication were prospectively enrolled into this study between June 2014 and February 2015. The articular cartilage of the trochlea was evaluated independently by 3 raters on axial and axial-oblique MRI and compared with arthroscopic findings (gold standard). The interrater and intrarater reliability of mild (International Cartilage Repair Society [ICRS] grades 1 or 2) and severe (ICRS grades 3 or 4) lesions on MRI were assessed as well as the sensitivity, specificity, positive predictive value, and negative predictive value., Results: A total of 99 knees in 96 patients were included in the study. Interrater and intrarater agreement for the identification of severe lesions were moderate to good on the proximal trochlea and fair to moderate on the distal trochlea. No significant differences in sensitivity were found between axial and axial-oblique scans for any grade of lesion (55% vs 51%, respectively; P = .700) or for severe lesions (61% vs 52%, respectively; P = .289). Similarly, specificity for detecting severe lesions was not significantly different between axial and axial-oblique scans (95% vs 87%, respectively; P = .219). Last, no significant differences in sensitivity or specificity were found between MRI sequences when separately evaluating proximal and distal trochlear lesions (all P > .05)., Conclusion: The axial-oblique sequence was unable to improve the sensitivity of MRI in detecting articular cartilage lesions on the trochlea. Both conventional axial and axial-oblique sequences, reviewed independently of the complete MRI series, had low sensitivity in detecting trochlear articular cartilage lesions. For this reason, clinicians should utilize all MRI planes to evaluate the articular cartilage of the trochlea. Future studies should focus on improving MRI techniques for detecting and characterizing cartilage lesions of the trochlea., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: R.F.L. is a consultant for and receives royalties from Arthrex, Ossur, and Smith & Nephew. J.J.M. and A.G.G. have received research and educational funding from Arthrex, Smith & Nephew, and DJO. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Background: The medial collateral ligament (MCL) is one of the most commonly injured structures in the knee, especially in young athletes. The impact of MCL injury on National Football League (NFL) performance in elite collegiate athletes has not yet been described in the literature., Purpose: We aim to (1) describe the prevalence and severity of MCL injuries in NFL Combine participants, (2) detail injury management, and (3) analyze the impact of MCL injury on NFL performance in terms of draft position, games played, games started, and snap percentage., Study Design: Cohort study; Level of evidence, 3., Methods: A retrospective review of all NFL Combine participants from 2009 to 2015 was performed by reviewing medical records and imaging reports from the combine to identify all players with MCL injuries. A control group was developed from the players evaluated at the combine without MCL injury. For each affected knee, the MCL injury was classified by location and severity based on results of magnetic resonance imaging (MRI). Each player's respective NFL draft position, number of NFL games played, number of NFL games started, and NFL snap percentage for the first 2 seasons in the league were collected through the use of NFL.com and Pro-Football-Focus, which are web-based, publicly accessible, comprehensive sports statistics databases., Results: A total of 2285 players participated in the NFL Combine between 2009 and 2015. Three hundred one athletes (13.2%) were identified as having MCL injuries; 36 (12%) of the athletes with MCL injury presented with bilateral injuries, for a total of 337 MCL injuries. Additional soft tissue injury was identified on 187 of 337 (55%) MRIs. Players with a history of MCL injury were more likely to play at least 2 years in the NFL compared with those in the control group ( P = .003). Players who had isolated MCL injury performed significantly better compared with athletes who had combined injuries with regard to draft position ( P = .034), proportion playing at least 2 seasons in the NFL ( P = .022), games played ( P = .014), and games started ( P = .020) in the first 2 years. No significant difference was found between players who underwent operative versus nonoperative management of their MCL injury., Conclusion: A relatively high percentage of players at the NFL Combine had evidence of MCL injury (13%). A prior history of MCL tear had no negative impact on an athlete's NFL performance. Players who had isolated MCL injury performed significantly better compared with athletes who had combined injuries with regard to draft position, proportion playing 2 seasons or more in the NFL, and games played and started in the first 2 years., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: C.A.L. receives research support from Novartis Pharmaceuticals and Smith & Nephew. M.D.P. is a consultant for Arthrex, Kairos Surgical, DePuy, and Arthrosurface. J.P.B. receives royalties from Arthrex. R.F.L. receives royalties from Arthrex, Ossur, and Smith & Nephew; is a consultant for Arthrex, Ossur, and Smith & Nephew; and receives research support from Arthrex, Linvatec, Ossur, and Smith & Nephew. M.T.P. receives royalties from Arthrex and SLACK Inc and is a consultant for Arthrex and the Joint Restoration Foundation (Allosource).

Background: Labral tears confirmed by magnetic resonance imaging (MRI) are a relatively common injury among collegiate athletes and can influence a player's ability to compete at the professional level., Purpose: To determine the prevalence of MRI-confirmed shoulder labral injuries in collegiate football players entering the National Football League (NFL) Combine and to further describe these injuries by tear location, player position, history of surgical intervention, and associated concomitant shoulder injuries., Study Design: Descriptive epidemiology study., Methods: Data from 2009 to 2015 were retrospectively collected through review of the injury data registry available to the medical and training staff of all NFL teams following the completion of the NFL Combine. After players with potential labral tears were identified through history and examination, their MRIs were reviewed by 2 fellowship-trained orthopaedic sports medicine surgeons. Players diagnosed with a labral tear confirmed by MRI were separated for further analysis., Results: A total of 2285 players were analyzed for the presence of labral tears at the NFL Combine. Overall, 377 shoulders (in 340/2285 players; 14.9%) demonstrated MRI evidence of labral tear; whereas linebackers had the highest rate of labral tear (19.2%), linemen had significantly higher risk for labral injury in at least 1 shoulder (odds ratio, 1.31; 95% CI, 1.02-1.67; P = .029) compared with nonlinemen. Of the 377 shoulders analyzed, 115 (30.5%) exhibited an anterior labral tear, 131 (34.7%) had a posterior labral tear, and 131 (34.7%) had combined anterior and posterior tears. One hundred twenty (31.8%) shoulders had superior labral anterior-posterior (SLAP) tears. A total of 203 (53.8%) shoulders demonstrated evidence of previous surgical intervention on imaging., Conclusion: Injury involving the labrum is relatively common among participants at the NFL Combine, especially linebackers and linemen. Further investigation is necessary to determine the impact these injuries have on player draft position and NFL performance., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: S.M. receives research support from DJO and Smith & Nephew. S.J.F. receives research support from DJO. J.P.B. receives royalties from Arthrex. R.F.L. receives royalties from Arthrex, Ossur, and Smith & Nephew; is a paid consultant for Arthrex, Ossur, and Smith & Nephew; and receives research support from Arthrex, Linvatec, Ossur, and Smith & Nephew. M.T.P. receives royalties from Arthrex and Slack Inc and is a paid consultant for Arthrex and Joint Restoration Foundation (AlloSource).

Background: A need exists for a functional anterior cruciate ligament (ACL) brace that dynamically supports the knee joint to match the angle-dependent forces of a native ACL, especially in the early postoperative period., Purpose/hypothesis: The purpose of this study was to quantify the posteriorly directed external forces applied to the anterior proximal tibia by both a static and a dynamic force ACL brace. The proximal strap forces applied by the static force brace were hypothesized to remain relatively constant regardless of knee flexion angle compared with those of the dynamic force brace., Study Design: Controlled laboratory study., Methods: Seven healthy adult males (mean age, 27.4 ± 3.4 years; mean height, 1.8 ± 0.1 m; mean body mass, 84.1 ± 11.3 kg) were fitted with both a static and a dynamic force ACL brace. Participants completed 3 functional activities: unloaded extension, sit-to-stand, and stair ascent. Kinematic data were collected using traditional motion-capture techniques while posteriorly directed forces applied to the anterior aspect of both the proximal and distal tibia were simultaneously collected using a customized pressure-mapping technique., Results: The mean posteriorly directed forces applied to the proximal tibia at 30° of flexion by the dynamic force brace during unloaded extension (80.2 N), sit-to-stand (57.5 N), and stair ascent (56.3 N) activities were significantly larger, regardless of force setting, than those applied by the static force brace (10.1 N, 9.5 N, and 11.9 N, respectively; P < .001)., Conclusion: The dynamic force ACL brace, compared with the static force brace, applied significantly larger posteriorly directed forces to the anterior proximal tibia in extension, where the ACL is known to experience larger in vivo forces. Further studies are required to determine whether the physiological behavior of the brace will reduce anterior knee laxity and improve long-term patient outcomes., Clinical Relevance: ACL braces that dynamically restrain the proximal tibia in a manner similar to physiological ACL function may improve pre- and postoperative treatment., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: Össur funded this study and provided unrestricted, in-kind donations of the braces utilized in this study. R.F.L. is a consultant for and receives royalties from Össur, Arthrex, and Smith & Nephew.

Background: The biomechanical effects of lateral meniscal posterior root tears with and without meniscofemoral ligament (MFL) tears in anterior cruciate ligament (ACL)-deficient knees have not been studied in detail., Purpose: To determine the biomechanical effects of the lateral meniscus (LM) posterior root tear in ACL-intact and ACL-deficient knees. In addition, the biomechanical effects of disrupting the MFLs in ACL-deficient knees with meniscal root tears were evaluated., Study Design: Controlled laboratory study., Methods: Ten paired cadaveric knees were mounted in a 6-degrees-of-freedom robot for testing and divided into 2 groups. The sectioning order for group 1 was (1) ACL, (2) LM posterior root, and (3) MFLs, and the order for group 2 was (1) LM posterior root, (2) ACL, and (3) MFLs. For each cutting state, displacements and rotations of the tibia were measured and compared with the intact state after a simulated pivot-shift test (5-N·m internal rotation torque combined with a 10-N·m valgus torque) at 0°, 20°, 30°, 60°, and 90° of knee flexion; an anterior translation load (88 N) at 0°, 30°, 60°, and 90° of knee flexion; and internal rotation (5 N·m) at 0°, 30°, 60°, 75°, and 90°., Results: Cutting the LM root and MFLs significantly increased anterior tibial translation (ATT) during a pivot-shift test at 20° and 30° when compared with the ACL-cut state (both P s < .05). During a 5-N·m internal rotation torque, cutting the LM root in ACL-intact knees significantly increased internal rotation by between 0.7° ± 0.3° and 1.3° ± 0.9° (all P s < .05) except at 0° ( P = .136). When the ACL + LM root cut state was compared with the ACL-cut state, the increase in internal rotation was significant at greater flexion angles of 75° and 90° (both P s < .05) but not between 0°and 60° (all P s > .2). For an anterior translation load, cutting the LM root in ACL-deficient knees significantly increased ATT only at 30° ( P = .007)., Conclusion: The LM posterior root was a significant stabilizer of the knee for ATT during a pivot-shift test at lower flexion angles and internal rotation at higher flexion angles., Clinical Relevance: Increased knee anterior translation and rotatory instability due to posterior lateral meniscal root disruption may contribute to increased loads on an ACL reconstruction graft. It is recommended that lateral meniscal root tears be repaired at the same time as an ACL reconstruction to prevent possible ACL graft overload., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: Smith & Nephew provided funding for this study and an in-kind donation of surgical supplies. R.F.L. is a consultant for Arthrex, Ossur, and Smith & Nephew; receives royalties from Arthrex and Smith & Nephew; receives research support from Arthrex and Smith & Nephew; has received grants from Health East, Norway and an NIH R-13 grant for biologics; has patents pending with Ossur and Smith & Nephew; and patents with royalties paid from Ossur, Smith & Nephew, and Arthrex. G.M. has received grants from Health South East (Helse Sør-Øst) Norway and Arthrex.

Background: A subset of patients have clinical internal and/or external knee rotational instability despite no apparent injury to the cruciate or collateral ligaments., Purpose/hypothesis: The purpose of this study was to assess the effect of sequentially cutting the posterolateral, anterolateral, posteromedial, and anteromedial structures of the knee on rotational stability in the setting of intact cruciate and collateral ligaments. It was hypothesized that cutting of the iliotibial band (ITB), anterolateral ligament and lateral capsule (ALL/LC), posterior oblique ligament (POL), and posteromedial capsule (PMC) would significantly increase internal rotation, while sectioning of the anteromedial capsule (AMC) and the popliteus tendon and popliteofibular ligament (PLT/PFL) would lead to a significant increase in external knee rotation., Study Design: Controlled laboratory study., Methods: Ten pairs (N = 20) of cadaveric knees were assigned to 2 sequential cutting groups (group 1: posterolateral-to-posteromedial [PL → PM] and group 2: posteromedial-to-posterolateral [PM → PL]). Specimens were subjected to applied 5-N·m internal and external rotation torques at knee flexion angles of 0°, 30°, 60°, and 90° while intact and after each cut state. Rotational changes were measured and compared with the intact and previous cut states., Results: Sectioning of the ITB significantly increased internal rotation at 60° and 90° by 5.4° and 6.2° in group 1 (PL → PM) and 3.5° and 3.8° in group 2 (PM → PL). PLT/PFL complex sectioning significantly increased external rotation at 60° and 90° by 2.7° and 2.9° in group 1 (PL → PM). At 60° and 90° in group 2 (PM → PL), ALL/LC sectioning produced significant increases in internal rotation of 3.1° and 3.5°, respectively. In group 2 (PM → PL), POL sectioning produced a significant increase in internal rotation of 2.0° at 0°. AMC sectioning significantly increased external rotation at 30° to 90° of flexion with a magnitude of change of <1° in both groups 1 (PL → PM) and 2 (PM → PL)., Conclusion: Collectively, the anterolateral corner structures provided primary internal rotation control of the knee from 60° to 90° of knee flexion in knees with intact cruciate and collateral ligaments. The ITB was the most significant primary stabilizer of internal rotation. The POL had a primary role for internal rotational stability at full extension. The PLT/PFL complex was a primary stabilizer for external rotation of the knee at 60° and 90°., Clinical Relevance: This study delineates the primary and secondary roles of the ITB, ALL/LC, POL, and PLT/PFL to rotatory stability of the knee and provides new information to understand knee rotational instabilities., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: R.F.L. is a consultant for Arthrex, Ossur, and Smith & Nephew; receives royalties from Arthrex and Smith & Nephew; and receives research support from Arthrex, Ossur, and Smith & Nephew. J.M.S. receives royalties from Arthrex, Tornier, and Zimmer-Biomet; receives other financial/material support from Smith & Nephew ; receives research support from Synthes and Zimmer-Biomet; is a paid consultant for Tornier, Zimmer-Biomet, and Wright Medical Technology; is a paid presenter for Tornier, Zimmer-Biomet, and Wright Medical Technology; and has stock/stock options in Tornier. G.M. has received research grants from South-Eastern Norway Health Authorities (Helse Sør-Øst) and Arthrex.

Background: Information on the incidence, injury mechanisms, ligament injury patterns, and associated injuries of knee dislocations is lacking in the literature. There is a need to characterize ligament injury patterns and associated injuries in knee dislocations to avoid missing common associated diagnoses and to plan surgical treatment., Purpose: To evaluate patient demographics, ligament injury patterns and associated injury patterns, and associated injuries in patients with knee dislocation., Study Design: Cross-sectional study; Level of evidence, 3., Methods: A total of 303 patients with knee dislocations treated at a single level 1 trauma center were followed prospectively. Injury mechanism; ligament injury patterns; associated neurovascular, meniscal, and cartilage injuries; and surgical complications were recorded. The Schenck knee dislocation classification was used to classify the ligament injury patterns., Results: The mean age at injury was 37.8 ± 15.3 years. Of the 303 patients included, 65% were male and 35% were female. There was an equal distribution of high-energy and low-energy injuries. Injury to 3 major ligaments was the most common, with Schenck classification type KD III-M constituting 52.4% of the injuries and KD III-L comprising 28.1%. Meniscal injuries and cartilage injuries occurred in 37.3% and 28.3% of patients, respectively. Patients with acute injuries had significantly lower odds of a cartilage injury than those with chronic injuries (odds ratio [OR], 0.28; 95% CI, 0.15-0.50; P < .001). Peroneal nerve injuries were recorded in 19.2% of patients (10.9% partial and 8.3% complete deficit), while vascular injuries were recorded in 5%. The odds of having a common peroneal nerve injury were 42 times greater ( P < .001) among those with posterolateral corner injury (KD III-L) than those without. The odds for popliteal artery injury were 9 times greater ( P = .001) among those with KD III-L injuries than other ligament injury types., Conclusion: Medial-sided bicruciate injuries were the most common injury pattern in knee dislocations. Cartilage injuries were common in chronically treated patients. There was a significant risk of peroneal nerve injury with lateral-sided injuries., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: This study was funded by the South-Eastern Norway Health Authorities (Helse Sør-Øst, Norway). L.E. is a consultant for and receives royalties from Arthrex, receives research support from Biomet and Smith & Nephew, and has stock/stock options in iBalance. R.F.L. is a consultant for, receives royalties from, and receives research support from Arthrex, Ossur, and Smith & Nephew. G.M. has received research grants from the South-Eastern Norway Health Authorities (Helse Sør-Øst) and Arthrex.

Background: Quantitative magnetic resonance imaging (MRI) techniques, such as T2 and T2 star (T2*) mapping, have been used to evaluate ligamentous tissue in vitro and to identify significant changes in structural integrity of a healing ligament. These studies lay the foundation for a clinical study that uses quantitative mapping to evaluate ligaments in vivo, particularly the posterior cruciate ligament (PCL). To establish quantitative mapping as a clinical tool for identifying and evaluating chronic or acute PCL injuries, T2 and T2* values first must be determined for an asymptomatic population., Purpose: To quantify T2 and T2* mapping properties, including texture variables (entropy, variance, contrast, homogeneity), of the PCL in an asymptomatic population. It was hypothesized that biomarker values would be consistent throughout the ligament, as measured across 3 clinically relevant subregions (proximal, middle, and distal thirds) in the asymptomatic cohort., Study Design: Cross-sectional study; Level of evidence, 4., Methods: Unilateral knee MRI scans were acquired for 25 asymptomatic subjects with a 3.0-T MRI system using T2 and T2* mapping sequences in the sagittal plane. The PCL was manually segmented and divided into thirds (proximal, middle, and distal). Summary statistics for T2 and T2* values were calculated. Intra- and interrater reliability was assessed across 3 raters to 2 time points., Results: The asymptomatic PCL cohort had mean T2 values of 36.7, 29.2, and 29.6 ms in the distal, middle, and proximal regions, respectively. The distal PCL exhibited significantly higher mean, variance, and contrast and lower homogeneity of T2 values than the middle and proximal subregions (P < .05). T2* results exhibited substantial positive skew and were therefore presented as median and quartile (Q) values. Median T2* values were 7.3 ms (Q1-Q3, 6.8-8.9 ms), 7.3 ms (Q1-Q3, 7.0-8.5 ms), and 7.3 ms (Q1-Q3, 6.4-8.2 ms) in the distal, middle, and proximal subregions, respectively., Conclusion: This is the first study to identify T2 and T2* mapping values, and their texture variables, for the asymptomatic PCL. The distal third of the PCL had significantly greater T2 values than the proximal or middle thirds., Clinical Relevance: T2 and T2* values of the asymptomatic PCL can provide a baseline for comparison with acute and chronic PCL injuries in future studies.

Background: Biomechanical studies have reported that the posterior cruciate ligament (PCL) functions as a restraint against excessive tibial internal rotation at higher degrees of knee flexion., Purpose: To investigate the use of a supine internal rotation (IR) test for the diagnosis of grade III PCL injuries. The hypothesis was that internal rotation would be greater in patients with grade III PCL injuries compared with other knee injuries and that the supine IR test would demonstrate excellent diagnostic accuracy., Study Design: Cohort study (diagnosis); Level of evidence, 2., Methods: A consecutive series of 309 patients underwent arthroscopic and/or open knee ligament reconstruction surgery. Seven patients were excluded based on the inability to perform a side-to-side comparison of internal rotation. Tibial internal rotation was assessed bilaterally on 302 patients during examination under anesthesia by a single orthopaedic surgeon measuring tibial tubercle excursion (mm) while applying internal rotation torque. Internal rotation was graded from 0 to 4 at 60°, 75°, 90°, 105°, and 120° of knee flexion. Data were collected and stored prospectively. The optimal threshold for the supine IR test was chosen based on maximization of the Youden index. Diagnostic accuracy parameters were calculated. Multiple logistic regression models were constructed to assess the influence of other knee pathologies on diagnostic accuracy., Results: Examination of the 22 PCL-deficient knees demonstrated an increase in tibial internal rotation at 60°, 75°, 90°, 105°, and 120° of knee flexion. The supine IR test had a sensitivity of 95.5%, a specificity of 97.1%, a positive predictive value of 72.4%, and a negative predictive value of 99.6% for the diagnosis of grade III PCL injuries. Posterolateral corner injury had a significant interaction with the supine IR test, increasing its sensitivity and decreasing its specificity., Conclusion: PCL-deficient knees demonstrated an increase in the side-to-side difference in tibial internal rotation compared with other knee pathologies. The supine IR test offers high sensitivity and specificity for grade III PCL injuries and may represent a useful adjunct for diagnosing PCL injuries.