Purpose
Matrix-induced autologous chondrocyte implantation (MACI) is a regenerative procedure aimed to recreate a hyaline-like repair tissue, restoring a biologically and biomechanically valid articular surface with durable clinical results. The purpose of this study is to assess patient reported outcome measures (PROMS) in a series of patients undergoing intervention to treat multiple defects to characterize and elucidate results when using the MACI graft in place of the previous ACI or CACI “sandwich” procedures.
Methods
A retrospective review of a prospective patient series was undertaken. The study population included patients with multiple pre-operative osteochondral defects undergoing MACI procedures with minimum 6-month post-operative follow-up. The primary study endpoint was defined as an improvement of pain scores as measured at a minimum of 6M post-operative compared to preoperative value. Secondary endpoints included IKDC, KOOS, Lysholm, and SF-12 scores. All procedures were performed by the senior author, a fellowship-trained sports orthopaedic surgeon. Differences in mean outcomes were assessed using a generalized linear mixed model with a Poisson distribution and a random patient effect to account for correlations over time. All P-values were adjusted for multiple comparisons using the Tukey-Kramer method with alpha less than 0.05 considered statistically significant.
Results
6 patients with mean age 41.8 years underwent MACI for their chondral defects. Mean follow up was 27.2 months (range 14-51 months). 66.7% of patients had two defects treated while 33.3% of patients had three lesions treated. 83% of the study group required no further procedures at 2-year follow-up. 1 patient required concomitant bone grafting. Table 1 demonstrates PROM at measured intervals of pre-op, 6 months, 12 months, and 24 months post-op with corresponding statistical significance. Statistically significant improvements were noted at 24 months follow up in 3 of 10 outcome measures (Fig 1).
Conclusion
MACI has shown some clinically relevant benefit at 2-year post-operative follow up in improving patient reported outcome measures in patients with multiple osteochondral defects.