The role of autologous chondrocyte implantation in the patellofemoral joint.

UNLABELLED: In a prospective study to determine the clinical effectiveness of autologous chondrocyte implantation, 45 patients reached a minimum followup of 2 years (range, 2-7 years; average, 46.4 months) after treatment involving the patellofemoral articulation. There were 28 men (61%) and 17 women (39%) and the average age of the patients was 37.5 years (range, 15-55 years). The treatment groups included (I) isolated patella, n = 8; (II) isolated trochlea, n = 9; (III) patella plus trochlea, n = 4; (IV) weightbearing condyle plus patella n = 2; (V) weightbearing condyle plus trochlea, n = 2; and (VI) weightbearing condyle plus patella plus trochlea n = 20. The average surface area per patella (n = 34) was 4.86 cm2 and per trochlea (n = 34) it was 5.22 cm2. The average resurfacing per knee (n = 45) was 10.45 cm2. We showed a postoperative improvement in quality of life as measured by the Short Form-36; Western Ontario and McMaster University Score, Knee Society Score, modified Cincinnati Score, and a patient satisfaction survey. There were eight failures (18%) as a result of a patella or trochlea failure. Seventy-one percent of patients rated their outcomes as good or excellent, 22% rated outcome as fair, and 7% rated outcome as poor. LEVEL OF EVIDENCE: Therapeutic Study, Level II-1 (prospective cohort study). See the Guidelines for Authors for a complete description of levels of evidence.