Combined Meniscus and Osteochondral Allograft Transplantation: Minimum Two-Year Follow-up with an Analysis of Failures

OBJECTIVES: The purpose of this investigation was to report mid- and long-term follow-up on the clinical outcomes of patients undergoing combined MAT and osteochondral allograft procedures for symptomatic knee pain in the setting of meniscal deficiency and focal cartilage damage. We hypothesized that patients undergoing combined MAT and osteochondral allograft will demonstrate improved pain and functional scores following surgery. METHODS: This was a prospective case series. Thirty two patients with a minimum two-year follow-up were identified who initially presented with persistent symptoms following meniscectomy and an isolated International Cartilage Repair Society (IRCS) Grade 3 or 4 defect of the femoral condyle underwent combined MAT and fresh osteochondral allograft transplantation. Demographic and intra-operative data, including condylar defect size, was recorded as well as pre- and post-operative International Knee Documentation Committee (IKDC), Short Form-12 (SF-12), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Lysholm scores. Pre- and post-operative data was compared with paired t-tests while the association between functional scores and condylar defect size, age, gender, and involved compartment were analyzed with regression analysis. An alpha value of 0.05 was set as significant with Bonferroni correction utilized in the case of multiple comparisons. RESULTS: Average follow up was 4.2 years (range 2-11). Mean condylar defect size was 4.7 ± 2.0 cm2 at the time of index procedure. Lysholm, IKDC, and all KOOS subdomains showed significant improvement from pre- to post-operatively (p < 0.001). Patients with a condylar defect of less than 4 cm2 had a significantly greater increase in pre- versus post-operative IKDC (p = 0.010), Lysholm (p = 0.018), and KOOS (p = 0.016) versus those with greater than 4 cm2. Femoral condyle defect size was also significantly inversely correlated with post-operative IKDC (p = 0.015), KOOS (p = 0.003), and Lysholm score (p = 0.010). Patient satisfaction with the procedure was 82%. CONCLUSION: Patients undergoing combined MAT and osteochondral allograft showed improved functional scores following surgery. There was an inverse association between post-operative functional scores and the size of the condylar defect.