Treatment of Large Osteochondral Defects with Spongiosaplasty and Collagen Type I Hydrogel-Based Autologous Chondrocyte Implantation

Clinical data suggest that the reconstruction of large osteochondral defects requires application of osseous cylinders to augment the bony defect. This prospective case series investigates the clinical outcome after impaction grafting as an alternative to osseous cylinder transplantation to reconstruct the subchondral bone plate. We report on three patients with large osteochondral defects of the femoral condyle (averaging 10.9 cm2) resulting from osteochondritis dissecans or osteonecrosis. Defects were treated with spongiosaplasty followed by matrix-based autologous chondrocyte implantation (MACI) using a collagen-I-hydrogel. The patients were examined at 3, 6, 12, 24, 36, 48, and 60 months after surgery. The follow-up included radiographs, MRI, patient/doctor assessment as well as the IKDC-2000 evaluation package (IKDC score). At final follow-up, all three patients were satisfied with the long-term outcome since free of pain. Their functional and activity levels were back to normal, which was also reflected in the obtained IKDC-scores. Radiographic and MRI imaging showed complete reconsolidation of the subchondral osseus defects and excellent integration of the implanted collagen based matrix with the surrounding hyaline cartilage. Therefore, autologous spongiosaplasty as an alternative to the transplantation of osseous cylinders is a sufficient technique to reconstruct the subchondral bone plate in patients with large osteochondral defects.