Objectives:Retear of an ACL after an ACL reconstruction (ACLR) is devastating for all involved. Understanding risk factors and predictors of subsequent ACL tear after an ACLR is vital for patient education of subsequent risk of injury and if a predictor is modifiable, to make adjustments to minimize the risk of repeat ACL tear. The objectives of this study were 1) to identify the risk factors and predictors for ispilateral and contralateral ACL tears after primary ACLR and 2) to compare retear risk between the 2002/03 and 2007/08 cohorts. This is the largest and most comprehensive prospective analysis of this kind in the literature.Methods:Data from the 2002-2008 MOON database was used to identify risk factors for ACL retear. Subjects who had a primary ACLR with no history of contralateral knee surgery and had 2 year follow-up data were included. Subjects who had multiligament surgery were excluded. Graft type (auto-BTB, auto-hamstring, allograft), age, Marx score at time of index surgery, sport played post ACLR, sex, smoking status, lateral meniscus tear at the time of ACLR, medial meniscus tear at the time of ACLR, BMI, and MOON site were evaluated to determine their contribution to both ipsilateral retear and contralateral ACL tear. The analysis was repeated using the 2002/3 and 2007/8 cohort and included age, graft, sex, and Marx. An ANOVA with post-hoc analysis was performed to detect significant differences in age and Marx score by graft type over time.Results:A total of 2801 subjects met all inclusion/exclusion criteria. There were 165/2801 (5.89%) ipsilateral and 177/2801 (6.32%) contralateral ACL tears identified in the cohort at the two year follow-up. The odds of ipsilateral retear are 1.68 times greater for hamstring autograft (p=0.04) and 4.67 times greater for an allograft (p<0.001) compared to auto-BTB. The odds of ipsilateral retear decrease by 8% for every yearly increase in age (p < 0.001) and increases by 6% for every increased point on the Marx score (p = 0.017). The odds of contralateral ACL tear increase by 7% for every increased point on the Marx score (p = 0.004) and decreases by 5% for every one point increase in BMI (p = 0.03). In 2002/3, there were 61/815 (7.5%) retears compared to 37/1056 (3.5%) in 2007/8. The odds of retear by for the 2002/03 and 2007/08 cohorts are summarized in table 1. The mean age (figure 1) of subjects receiving BTB and hamstring remained constant over time whereas the mean age of subjects receiving allograft rose by seven years (p < 0.001). Hamstring use was a predictor of retear compared to BTB in the 02/03 group (7.9% vs. 4.2%), but not in the 07/08 group (4.1% vs. 3.4%).Conclusion:Age, activity, and graft type were predictors of increased risk of ipsilateral graft failure after ACLR. Higher activity and lower BMI were found to be risk factors in contralateral ACL tears. Allograft use in young active patients was shown to be a risk factor for graft retear in the 02/03 group, subsequent to this, graft choice changed to using allografts in older and less active ...

Purpose The purpose of this study is to evaluate the effect of graft size on patient-reported outcomes and revision risk following ACL reconstruction. Methods A retrospective chart review of prospectively collected cohort data, 263 of 320 consecutive patients (82.2%) undergoing primary ACL reconstruction with hamstring autograft were evaluated. Graft size, femoral tunnel drilling technique, patient age, sex, and BMI at the time of ACL reconstruction, pre-operative and 2-year post-operative KOOS and IKDC scores, and whether each patient underwent revision ACL reconstruction during the 2 year follow-up period were recorded. Revision was used as a marker for graft failure. The relationship between graft size and patient-reported outcomes was determined by multiple linear regression. The relationship between graft size and risk of revision was determined by dichotomizing graft size at 8mm and stratifying by age. Results After controlling for age, sex, operative side, surgeon, BMI, graft choice, and femoral tunnel drilling technique, a 1 mm increased in graft size was noted to correlate with 3.3-point increase in the KOOS-pain subscale (p = 0.003), a 2.0-point increased in the KOOS activities of daily living subscale (p = 0.034), a 5.2-point increase in the KOOS-sport/recreation function subscale (p = 0.004), and a 3.4-point increase in the subjective IKDC score (p = 0.026). Revision was required in 0 of 64 patients (0.0%) with grafts greater than 8mm in diameter and 14 of 199 patients (7.0%) with 8 mm or smaller grafts (p = 0.037). Among patients age 18 and under, revision was required in 0 of 14 patients (0.0%) with grafts greater than 8mm in diameter and 13 of 71 patients (18.3 %) with 8 mm or smaller grafts. Conclusions Smaller hamstring autograft size is a predictor of poorer KOOS Sport and Recreation function 2 years following primary ACL reconstruction. Larger sample size is required to confirm the relationship between graft size and risk of revision ACL reconstruction. Level of Evidence Level 3

The contralateral normal knee anterior cruciate ligament is at a similar risk of anterior cruciate ligament tear (3.0%) as the anterior cruciate ligament graft after primary anterior cruciate ligament reconstruction (3.0%).

Background A patellar dislocation is a common knee injury in the young, athletic patient population. Recent trends indicate that the use of long-term nonoperative treatment is decreasing, and surgical intervention is more commonly recommended for those patients who fail initial nonoperative management with recurrent patellar dislocations. Medial patellofemoral ligament (MPFL) reconstruction has become increasingly utilized in this regard. Purpose To evaluate outcomes, particularly return to sports and its relationship to postoperative instability, of isolated MPFL reconstruction for the treatment of recurrent patellar dislocations. Study Design Systematic review and meta-analysis. Methods A review of the current literature was performed using the terms “medial patellofemoral ligament reconstruction” and “MPFL reconstruction” in the electronic search engines PubMed and EBSCOhost (CINAHL, MEDLINE, SPORTDiscus) on July 29, 2015, yielding 1113 abstracts for review. At the conclusion of the search, 14 articles met the inclusion criteria and were included in this review of the literature. Means were calculated for population size, age, follow-up time, and postoperative Tegner scores. Pooled estimates were calculated for postoperative Kujala scores, return to play, total risk of postoperative instability, risk of positive apprehension sign, and risk of reoperation. Results The mean patient age associated with MPFL reconstruction was 24.4 years, with a mean postoperative Tegner score of 5.7. The pooled estimated mean postoperative Kujala score was 85.8 (95% CI, 81.6–90.0), with 84.1% (95% CI, 71.1%–97.1%) of patients returning to sports after surgery. The pooled total risk of recurrent instability after surgery was 1.2% (95% CI, 0.3%–2.1%), with a positive apprehension sign risk of 3.6% (95% CI, 0%–7.2%) and a reoperation risk of 3.1% (95% CI, 1.1%–5.0%). Conclusion A high percentage of young patients return to sports after isolated MPFL reconstruction for chronic patellar instability, with short-term results demonstrating a low incidence of recurrent instability, postoperative apprehension, and reoperations.

Background Identifying risk factors for inferior outcomes after ACL reconstruction (ACLR) is important for prognosis and future treatment. The goal of this study was to determine whether articular cartilage and meniscal variables are predictive of 3 validated sports outcome instruments after ACLR. Hypothesis/Purpose We hypothesized that articular cartilage lesions and meniscus tears/treatment would be predictors of the IKDC, KOOS (all 5 subscales), and Marx activity level at 6 years following ACLR. Study Design Prospective cohort, Level 1 Methods Between 2002 and 2004, 1512 ACLR subjects were prospectively enrolled and followed longitudinally with the IKDC, KOOS, and Marx activity score completed at entry, 2, and 6 years. A logistic regression model was built incorporating variables from patient demographics, surgical technique, articular cartilage injuries, and meniscus tears/treatment to determine the predictors (risk factors) of IKDC, KOOS, and Marx at 6 years. Results We completed a minimum follow-up on 86% (1307/1512) of our cohort at 6 years. The cohort was 56% male, had a median age of 23 years at the time of enrollment, with 76% reporting a non-contact injury mechanism. Incidence of concomitant pathology at the time of surgery consisted of the following: articular cartilage (medial femoral condyle [MFC]-25%, lateral femoral condyle [LFC]-20%, medial tibial plateau [MTP]-6%, lateral tibial plateau [LTP]-12%, patella-20%, trochlear-9%) and meniscal (medial-38%, lateral-46%). Both articular cartilage lesions and meniscal tears were significant predictors of 6-year outcomes on IKDC and KOOS. Grade 3 or 4 articular cartilage lesions (excluding patella) significantly reduced IKDC and KOOS scores at 6 years. IKDC demonstrated worse outcomes with the presence of a grade 3-4 chondral lesion on the MFC, MTP, and LFC. Likewise, KOOS was negatively affected by cartilage injury. The sole significant predictor of reduced Marx activity was the presence of a grade 4 lesion on the MFC. Lateral meniscus repairs did not correlate with inferior results, but medial meniscus repairs predicted worse IKDC and KOOS scores. Lateral meniscus tears left alone significantly improved prognosis. Small partial meniscectomies (<33%) on the medial meniscus fared worse, but conversely, larger excisions (>50%) on either the medial or lateral menisci improved prognosis. Analogous to previous studies, other significant predictors of lower outcome scores were lower baseline scores, higher BMI, lower education level, smoking, and ACL revisions. Conclusions Both articular cartilage injury and meniscal tears/treatment at the time of ACLR were significant predictors of IKDC and KOOS scores 6 years following ACLR. Similarly, having a grade 4 MFC lesion significantly reduced a patient’s Marx activity level score at 6 years.