Comparable Clinical and Functional Outcomes Between Osteochondral Allograft Transplantation and Autologous Chondrocyte Implantation for Articular Cartilage Lesions in the Patellofemoral Joint at a Mean Follow-Up of 5 Years

Purpose: To assess clinical outcomes and return to sport (RTS) rates among patients who undergo osteochondral allograft (OCA) transplantation and autologous chondrocyte implantation (ACI) or matrix-induced autologous chondrocyte implantation (MACI), for patellofemoral articular cartilage defects. Methods: A retrospective review of patients who underwent an OCA or ACI/MACI from 2010 to 2020 was conducted. Patient-reported outcomes collected included visual analog scale for pain/satisfaction, Knee Injury and Osteoarthritis Outcome Score (KOOS), and RTS. The percentage of patients that met the patient acceptable symptom state for KOOS was recorded. Logistic regression was used to identify predictors of worse outcomes. Results: A total of 95 patients were included (78% follow-up) with ACI or MACI performed in 55 cases (57.9%) and OCA in 40 (42.1%). A tibial tubercle osteotomy was the most common concomitant procedure for OCA (66%) and ACI/MACI (98%). Overall, KOOS pain was significantly poorer in OCA than ACI/MACI (74.7, 95% confidence interval 68.1-81.1 vs 83.6, 95% confidence interval 81.3, 88.4, P = .012), whereas the remaining KOOS subscores were nonsignificantly different (all P> .05). Overall, RTS rate was 54%, with no significant difference in return between OCA or ACI/MACI (52% vs 58%, P = .738). There were 26 (27%) reoperations and 5 (5%) graft failures in the entire group. Increasing age was associated with lower satisfaction in OCA and poorer outcomes in ACI/MACI, whereas larger lesion area was associated with lower satisfaction and poorer outcomes in ACI/MACI. Conclusions: Clinical and functional outcomes were similar in patients who underwent OCA or ACI/MACI for patellofemoral articular cartilage defects at a mean follow-up of 5 years. Patients who received OCA had a greater proportion of degenerative cartilage lesions and, among those with trochlear lesions, reported greater pain at final follow-up than their ACI/MACI counterparts. Overall, increasing age and a larger lesion size were associated with worse patient-reported outcomes.