Mid-term outcomes of arthroscopic osteochondral autograft transplantation for focal chondral defects of the knee

Abstract

Objectives: Osteochondral autograft transplantation (OAT) for the management of cartilage defect involves direct transfer of hyaline cartilage to the defect site. The study aims to assess mid-term functional outcomes of arthroscopic treatment of focal chondral defects of the knee using the OAT technique. Materials and Methods: In this prospective follow-up study, patients who had previously undergone an OAT procedure for chondral defects of the knee at least 2 years prior were included. All the cartilage defects were treated arthroscopically with one or two plugs. Patients were followed up at 2 time points – in June 2016 and June, 2020. The International Knee Documentation Committee (IKDC) score and Tegner activity scale (TAS) were recorded preoperatively and at both follow-ups. Results: There were 20 patients with 21 focal cartilage defects, comprising 14 males and 6 females, with an average age of 30.9 ± 7 years and mean body mass index (BMI) of 27.2 ± 4 kg/m2. The first follow-up was after a mean 42.4 ± 12 months and the second after mean 90.4 ± 11.9 months post-surgery. The IKDC score improved significantly at both follow-ups compared to pre-operative scores (P < 0.001). At the first follow-up, the mean change in IKDC score was 25.3 ± 16.7 with 14 patients (70%) achieving minimal clinically important difference (MCID) but only 5 (25%) achieving substantial clinical benefit (SCB). At the second follow-up, 16 patients (80%) achieved MCID and 8 (40%) achieved SCB in IKDC score, with a mean change of 28.3 ± 12.6. The TAS showed statistically significant improvement at the first follow-up (P = 0.011), but not at the second follow-up (P = 0.052). Conclusion: OAT for focal cartilage defects of the knee is an excellent option as it provides clinically significant and incremental improvement in functional results in the mid-term. The results are not inferior even when a concomitant ligament or meniscus surgery is performed. Higher age or BMI does not have a negative impact on the outcomes.