A large knee osteochondral lesion treated using a combination of osteochondral autograft transfer and second-generation autologous chondrocyte implantation: A case report.

Background: Full-thickness knee cartilage defects greater than 4 cm2 are best treated with autologous chondrocyte implantation (ACI). Since the articular cartilage surrounding the site of implantation does not always have the normal thickness desirable for successful engraftment, there may be benefit in combining ACI with osteochondral autograft transfer, which provides immediate restoration of condylar contour and mechanical function.

Case presentation: A 19 year-old male who sustained a traumatic anterolateral femoral condyle osteochondral fracture underwent arthroscopic knee surgery three months after injury to harvest healthy cartilage to be sent to the Japan Tissue Engineering Co., Ltd. (J-TEC) for cartilage culture. The patient was re-admitted after four weeks to undergo a procedure using the Osteochondral Autograft Transfer System (OATS®) and the J-TEC autologous cultured cartilage (JACC®) system. Three 4.75-mm osteochondral cylindrical cores were harvested from non-weight-bearing areas of the knee and were transplanted to the lateral periphery of the lateral femoral condyle defect. The cultured cartilage was implanted to the remaining defect with a periosteal cover harvested from the anterolateral ridge of the lateral femoral condyle. Continuous passive range of motion exercises and gait retraining were immediately initiated, with strict no weight-bearing precaution on the operated limb. Partial weight-bearing was allowed four weeks after surgery, which was progressed to full weight-bearing after another two weeks.

Conclusion: ACI must be viewed as a complementary procedure to osteochondral transplantation and this hybrid technique appears to be a promising surgical approach and treatment option for large cartilage lesions, especially in the younger population.