Treatment of osteochondritis dissecans of the knee with a biomimetic scaffold. A prospective multicenter study.

PURPOSE:the aim of the present study was to evaluate the clinical outcome of the treatment of osteochondritis dissecans (OCD) of the knee with a type-I collagen-hydroxyapatite nanostructural biomimetic osteochondral scaffold. METHODS:twenty-three patients affected by symptomatic knee OCD of the femoral condyles, grade 3 or 4 of the International Cartilage Repair Society (ICRS) scale, underwent biomimetic scaffold implantation. The site of the defect was the medial femoral condyle in 14 patients, whereas in 9 patients the lateral femoral condyle was involved. The average size of the defects was 3.5±1.43 cm(2). All patients were clinically evaluated using the ICRS subjective score, the IKDC objective score, the EQ-VAS and the Tegner Activity Score. Minimum follow-up was two years. MRI was performed at 12 and 24 months after surgery and then every 12 months thereafter. RESULTS:the ICRS subjective score improved from the baseline value of 50.93±20.6 to 76.44±18.03 at the 12 months (p<0.0005) and 82.23± 17.36 at the two-year follow-up (p<0.0005). The IKDC objective score confirmed the results. The EQ-VAS showed a significant improvement from 3.15±1.09 to 8.15±1.04 (p<0.0005) at two years of follow-up. The Tegner Activity Score improvement was statistically significant (p<0.0005). CONCLUSIONS:biomimetic scaffold implantation was a good procedure for treating grade 3 and 4 OCD, in which other classic techniques are burdened by different limitations. This open one-step surgery gave promising stable results at short-term follow-up. LEVEL OF EVIDENCE:Level IV, therapeutic case series.