Abstract Introduction The autologous shaver-based minced cartilage implantation is increasingly used for the treatment of focal cartilage lesions of the knee. However, in the absence of randomised controlled studies on this specific technique, its efficacy in comparison to established cartilage repair methods is a matter of debate. Materials and methods Eleven patients (12 cases) were prospectively included in this study. One female patient was excluded due to conversion to total knee arthroplasty. All 11 analysed cases (8 females, 3 males; mean age: 42.7 ± 11.8 years, body mass index (BMI): 29.6 ± 6.1 kg/m 2 , lesion size: 3.2 ± 1.6 cm 2 ) received autologous shaver-based minced cartilage implantation (AutoCart™, Arthrex Inc.) due to full thickness cartilage lesion of the knee. The patients were evaluated preoperatively and at 6, 12- and 24-months follow-up, using the International Knee Documentation Committee (IKDC) Questionnaire, the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Visual Analog Scale (VAS) pain. The minimal clinically important difference (MCID) was calculated using the half-standard deviation method. Magnetic resonance imaging (MRI) was performed after 24 months and evaluated using the Magnetic resonance Observation of Cartilage Repair Tissue grading scale (MOCART) and the calculation of a T2-Index comparing T2 relaxation times of transplanted cartilage with intact cartilage of the same joint. Results Statistically significant improvement at 24 months follow up was observed for pain relief, as documented by the VAS and KOOS total, as well as the KOOS subsccores pain and activities of daily living. Out of 11 cases the MCID was reached in 9 cases considering VAS, 5 cases considering IKDC, 7 cases considering KOOS total and sport, 6 cases considering quality of life and 5 cases considering symptoms and activities of daily living. The postoperative mean MOCART score was 51.4 ± 22.0 and the mean T2-Index was 0.72 ± 0.18. In 3 of 11 postoperative MRIs no transplanted cartilage was observed. Conclusion Treatment of focal cartilage lesions at the knee with the autologous shaver-based minced cartilage implantation provided pain relief and improved function at 2 years follow up. Radiologic results indicated that on average the transplanted cartilage was different from hyaline cartilage, however, according to the T2-Index, in two cases the transplanted cartilage exhibited qualitative MR morphological properties similar to hyaline cartilage.
Pohl et al. (Fri,) studied this question.