Fig. 2

Comparison of an arthroscopic assessment at initial operation and at the time of second-look operation. a Patient of group 1 showed preexisting cartilage lesions on patellofemoral joint (patella; ICRS grade III cartilage lesions with about 15x15mm size, trochlea; ICRS grade III cartilage lesions with about 5x20mm size), b which were observed to be progressed at second-look operation (patella; ICRS grade III cartilage lesions with about 15x15mm size, trochlea; ICRS grade III cartilage lesions with about 20x25mm size). c Patient of group 2 without any preexisting cartilage lesions on patellofemoral joint d showed development of cartilage lesions at second-look operation (trochlea; ICRS grade III cartilage lesions with about 3x15mm size). ICRS International Cartilage Repair Society