Arthroscopic minced cartilage implantation provides superior clinical and magnetic resonance imaging outcomes compared to microfracture in patellar cartilage defects

Abstract

Purpose: To compare clinical and radiological outcomes of arthroscopic minced cartilage implantation (MCI) versus microfracture (MFx) in patients with patellar cartilage defects. Methods: A retrospective, single-centre cohort study was conducted on 46 patients treated between January 2021 and December 2022. Patients underwent either MCI (n = 26) or MFx (n = 20) with a minimum follow-up of 24 months (mean 35.7 ± 6.2). Magnetic resonance imaging (MRI) outcomes were assessed using the MOCART 2.0 Knee score by an independent blinded radiologist. Clinical outcomes included pain (visual analogue scale), function (self knee value), International Knee Documentation Committee, knee injury and osteoarthritis outcome score (KOOS) and patient acceptable symptom state (PASS)/minimal clinically important difference scores. Results: The MOCART 2.0 score was significantly higher in the MCI group (mean 86; 95% confidence interval [CI]: 83–92) compared to the MFx group (mean 66; 95% CI: 55–73) (p < 0.001). MCI patients achieved significantly greater improvements across all clinical measures, notably in the KOOS sport subscore (+33.2 vs. +5.3 points). PASS was achieved in 100% of MCI patients versus 35% of MFx patients (p < 0.001). No major complications or reoperations were reported. Conclusion: Both MCI and MFx improved clinical and MRI outcomes in patellar cartilage defects after 2 years, but MCI demonstrated significantly superior results across all parameters. Arthroscopic MCI appears to be an effective, safe, single-stage alternative to MFx for treating focal patellar cartilage lesions. Level of Evidence: Level III retrospective cohort study.