Treatment of deep cartilage defects of the knee with autologous chondrocyte transplantation: long-term results

The authors present the long-term results of surgical treatment of deep chondral defects of the knee (medial or lateral femoral condyle). They used the transplantation of autologous cultured chondrocytes in the form of a solid chondral graft. Indications for autologous chondrocyte transplantation most frequently included acute trauma to the knee. Patients with chondral lesions categorized as grades IIIa and IIIb by the Noyes-Stabler classification were indicated for this treatment. A small sample of healthy cartilage was harvested arthroscopically from the non-weight-bearing area of the knee and was sent to the Tissue Bank for chondrocyte cultivation. After 4 to 5 weeks the cultured chondrocytes were formed into a solid chondral graft, implanted at the damaged site of the medial or lateral femoral condyle and fixed with fibrin glue (Tissucol). Fifty-two patients, 34 males and 18 females (average age, 29 years range, 17 to 45 years) were treated using this method in the period from 2001 to 2009. Follow-up was 6 to 84 months, with an average of 46 months. Thirteen patients were examined by magnetic resonance imaging (MRI) 7 to 39 months (average, 19 months) after the implantation. Full incorporation the chondrograft was observed in 12 patients (92.3%). The clinical results were evaluated by the Lysholm scoring system (1, 2 and 5 years after the operation) and showed significant improvement. In 24 patients, the chondrograft quality was evaluated by immunohistochemical methods in samples taken by second-look arthroscopy from the borders of implantation sites. Hyaline chondral tissue was detected in 100% samples by microscopic examination, and collagen type II was present in 100% samples examined by imnunohistochemistry using haematoxylin-eosin staining. A significant improvement in knee function was recorded when the pre-operative and final follow-up stages were compared. The autologous chondrocyte transplantation showed a potential for the treatment of large cartilage defects. The excellent results achieved allowed the patients to return to normal activity levels.This method is also convenient when ligament reconstruction is necessary during one operation.