Aragonite-Based Scaffolds Are Effective Osteochondral Graft Substitutes for Osteochondral Defects of the Knee: A Systematic Review.

Purpose: To evaluate the outcomes and complication profiles after the implantation of aragonite-based scaffold osteochondral substitutes for the treatment of osteochondral lesions of the knee. Methods: Using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we completed a comprehensive search of the PubMed, Embase, and Medline databases in January 2025 to obtain studies reporting on outcomes after implantation of an aragonite-based scaffold in patients with osteochondral defects of the knee. Clinical studies were assessed for patient-reported outcome measures, failure rates, and magnetic resonance imaging findings. Risk-of-bias assessment was performed and the Methodological Index for Non-randomized Studies (MINORS) criteria were applied to appraise study quality. Results: Five studies were included for data analysis. In total, 526 patients with a mean age of 39.1 years (range, 31.6-42.0 years) were followed up for an average of 30.5 months (range, 12-78 months). Four studies evaluating Knee Injury and Osteoarthritis Outcome Scores reported mean improvements of 16.1 to 41.0 from preoperatively to final follow-up. Three studies reported improvements of 23.1 to 43 in International Knee Documentation Committee Subjective Knee Form scores. Failure, defined as any secondary intervention on the index knee, occurred in 0% to 13.6% of cases, and these rates were significantly lower than those for microfracture and arthroscopic debridement. Tapered scaffolds had lower failure rates than cylindrical designs (0% vs 8%-10.5%). Conclusions: Aragonite-based scaffolds in the treatment of osteochondral lesions of the knee show improved patient-reported outcomes and low failure rates at mean follow-up durations ranging from 12 to 78 months. Level of Evidence: Level IV, systematic review of Level I and IV studies.