Arthroscopy. 2026 Aug 24. doi: 10.1002/arj.70430. Online ahead of print.
ABSTRACT
PURPOSE: To determine the difference in reported outcomes and failures in retrospective versus prospective studies investigating the matrix-induced autologous chondrocyte implantation (MACI) procedure.
METHODS: PubMed, Embase, and Scopus were queried for studies investigating outcomes following the MACI procedure for knee cartilage defects. Studies selected included second- and third-generation MACI procedures. Inclusion criteria were as follows: (1) described study design, (2) was in English, and (3) had full-text available. Exclusion criteria were systematic review, meta-analysis, case reports, abstracts, and presentations. Year, study design, Modified Coleman Methodology Score, level of evidence, follow-up, intraoperative complications, postoperative complications, rate of graft failure, rate of graft hypertrophy, return to play rate, revision rate, and patient-reported outcome measures were collected. A 2-sample t-test was used to compare prospective and retrospective studies. Statistical significance was defined as a P value < .05.
RESULTS: A total of 28 studies were included for analysis. There were 19 prospective studies, consisting of 979 patients and 1021 knees, and 9 retrospective studies, consisting of 460 patients and 463 knees. There were significantly higher rates of graft failure in prospective studies compared with retrospective studies (4.30% vs 0.06%, P = .0043). There were no significant differences in graft hypertrophy, subsequent procedures, or other postoperative complications. Only 6 of 19 prospective studies and 0 of 9 retrospective studies reported return to sport. There were 8 different patient-reported outcome measures reported across the studies, with the most common being the Knee Injury and Osteoarthritis Outcome Score.
CONCLUSIONS: Prospective studies investigating MACI were more likely to report graft failure than retrospective studies but had similar findings in other outcome measures. Understanding differences in outcomes between retrospective and prospective studies is critical in evaluating the efficacy of the MACI procedure, as study design significantly influences reported findings.
LEVEL OF EVIDENCE: Level IV, systematic review of Level I, III, and IV studies.
PMID:42636292 | DOI:10.1002/arj.70430
