Autologous chondrocyte transplantation for the treatment of cartilage defects in the knee - Clinical results

Cartilage defects in the knee joint are common and have a bad tendency for healing due to the limited regeneration of hyaline cartilage. Surgeons have an ample choice of various operative treatment measures. Especially for th e treatment of larger lesions first results of autologous chondrocyte trans plantation (ACT) were published in 1993 [3]. Autologous chondrocytes are is olated from an arthoscopically harvested cartilage biopsy, cultured in vitr o and implanted in the defect under a periostal flap in a second procedure. In an international multi center study 1 051 patients treated with ACT bet ween 6/95 and 12/98 were documented with follow-up examinations after 12 mo nths (588 patients), 24 months (220 patients) and 36 months (40 patients). The majority of the defects (61.2 %) were localized on the medial femoral c ondyle, measuring 4.6 cm(2) and mostly described as grade III/IV lesions. T he clinical evaluation was performed using a modified Cincinnati knee ratin g system independently for clinician and patient. Evaluations showed an inc rease from 3.35 to 6.25 after 24 months and from 3.10 to 6.77 in a scale fr om 1 (bad) to 10 (excellent). ACT favours defects of the femur with an impr ovement rate of 85 %. Adverse events possibly related to ACT were described in 4.8 % of the patients. Diagnostic second-look arthroscopies are include d in the reoperation rate of 5.1 %. The presented data indicate autologous chondrocyte transplantation as an effective and safe option for the treatme nt of large full thickness cartilage defects in the knee joint.