Predictive Factors for Failure of Meniscal Repair: A Retrospective Dual-Center Analysis of 918 Consecutive Cases

BACKGROUND: Meniscal surgery is one of the most common surgical procedures performed by orthopaedic surgeons. Over the past decade, awareness has increased regarding the importance of meniscal preservation to prevent the development of osteoarthritis in the knee joint. Removal of meniscal tissue can lead to a high risk of cartilage degeneration, and moreover, meniscus-preserving surgery rather than meniscal resection is likely to have better long-term outcomes. Success rates after meniscal repair range from 60% to 95%, but many reports are based on a small number of patients. PURPOSE/HYPOTHESIS: The purpose of this study was to review all meniscal repairs and potential predictors for failure during a 12-year period. We hypothesized that meniscal anchors, lateral repairs, and repairs made in conjunction with an anterior cruciate ligament reconstruction (ACLR) would have fewer failures than meniscal arrows, medial repairs, and isolated repairs. We also hypothesized that younger patients and acute tears would be associated with fewer failures. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: This study was a dual-center, retrospective analysis on consecutive meniscal repairs. The surgical protocols were reviewed, including type of tear, location, associated injury to the knee, and surgery. The study endpoint was failure of repair, defined as a need for reoperation and secondary partial or total meniscal resection, within 3 years. Kaplan-Meier analysis was performed to assess repair survival, with multivariate Cox regression to adjust for confounders. RESULTS: A total of 954 meniscal repairs were performed on 918 patients (536 male patients [58%]; 382 female patients [42%]) with a mean age of 26 years (range, 12-60 years). The failure rate for the entire cohort was 22.5%. Bioabsorbable arrows had significantly more failures than all-inside sutures with anchors (hazard ratio [HR], 1.8; 95% CI, 1.2-2.5; P = .002). Medial meniscal repairs had a higher failure rate than lateral meniscal repairs (HR, 3.7; 95% CI, 2.3-6.0; P < .001). Simultaneous ACLR resulted in less failure than when no simultaneous ACLR was performed (HR, 0.5; 95% CI, 0.3-0.9; P = .009). Age at repair and acuity of tear did not affect the outcome (P = .6 and .07, respectively). CONCLUSION: The failure rate after meniscal repair was significantly higher on the medial side, especially when using arrows. Meniscal repairs performed concomitantly with an ACLR result in fewer reoperations.