To evaluate the development of postoperative patellofemoral osteoarthritis, we performed a retrospective clinical and radiographic study of 100 patients who had undergone anterior cruciate ligament reconstruction with a bone-patellar tendon-bone autograft an average of 7 years before the follow-up. Radiographic evaluation showed no patellofemoral osteoarthritis in 53 patients (group I), mild osteoarthritis in 34 patients (group II), moderate osteoarthritis in 12 patients, and severe osteoarthritis in 1 patient (group III, moderate and severe changes). The average shortening of the patellar tendon was 2.4 mm in group I, 3.9 mm in group II, and 6.8 mm in group III. The placement of the femoral or tibial tunnel of the graft, as measured from lateral radiographs, did not correlate significantly with the degree of patellofemoral osteoarthritis. Patients who developed patellofemoral osteoarthritis experienced worse final outcomes, were more often dissatisfied with the condition of the operated knee, experienced more frequent pain and swelling in the knee joint, and had poorer range of motion and poorer quadriceps muscle strength than did patients without patellofemoral osteoarthritis. Only three patients had an unstable knee, and degenerative changes in the tibiofemoral joint were uncommon.