Characterized Chondrocyte Implantation Results in Better Structural Repair when Treating Symptomatic Cartilage Defects of the Knee in a Randomized Controlled Trial versus Microfracture

As the natural healing capacity of damaged articular cartilage is poor, joint surface injuries are a prime target for regenerative medicine. Characterized chondrocyte implantation uses an autologous cartilage cell therapy product that has been optimized for its biological potency to form stable cartilage tissue in vivo. PURPOSE: To determine whether, in symptomatic cartilage defects of the femoral condyle, structural regeneration with characterized chondrocyte implantation is superior to repair with microfracture. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1.

Characterized chondrocyte implantation was compared with microfracture in patients with single grade III to IV symptomatic cartilage defects of the femoral condyles in a multicenter trial. Patients aged 18 to 50 years were randomized to characterized chondrocyte implantation (n = 57) or microfracture (n = 61). Structural repair was blindly assessed in biopsy specimens taken at 1 year using (1) computerized histomorphometry and (2) evaluation of overall histological components of structural repair. Clinical outcome was measured using the self administered Knee injury and Osteoarthritis Outcome Score. Adverse events were recorded throughout the study.