A multi-center study of repairing articular cartilage defects of the knee using cultured autologous chondrocytes

BACKGROUND: The regeneration ability of articular cartilage is limited. However, the emerging of tissue regeneration based on the use of autologous cells appears to offer great promise in repairing articular cartilage defects. OBJECTIVE: To evaluate the short-term effectiveness and safety of autologous chondrocyte implantation (ACI). DESIGN, TIME AND SETTING: A prospective study was performed at the eighty university hospitals and general hospitals in Korea from March 2001 to April 2006. PARTICIPANTS: Two hundred and sixty-one patients with articular cartilage injury of the knee were selected, including 169 males, 92 females, with the mean age of 36.47 years (ranged: 15-70 years old), and the mean size of chondral defect was 4.91 cm² (ranged: 2.0-20.0 cm ²). Totally 215 cases were femoral condyle injury, 30 cases with trochlear, 25 cases with patellar, and 2 cases with tibia defects. METHODS: A total of 200-300 mg of cartilage tissue was obtained from a non-weight-bearing portion of the knee, followed by in vitro culture and implanted into defect of articular cartilage. All cases received a 6-month follow-up, and improvement of knee society score after ACI was evaluated by Knee Society Score-A (KSS-A) and Knee Society Score-B (KSS-B) system. MAIN OUTCOME MEASURES: KSS-A and KSS-B score of defected areas after ACI. RESULTS: All patients received followed-up without any loss. The KSS-A was 63.55±18.47 and 88.74±11.47 prior to and at 6 months after implantation, the difference had significance (P < 0.05). The KSS-B was 59.56±24.92 and 85.13±14.67 respectively prior to and at 6 months after implantation, which had obviously difference (P < 0.05). The joint pain, activity, stability, flexion contracture, locomotor activity and stair climbing were obviously improved. The effective rate was 97.3% and excellent and good rate was 89.3%. CONCLUSION: ACI can achieve a good result in treating knee articular cartilage defects, which can encourage the recover of knee function.