Repair of Large Chondral Defects of the Knee with Autologous Chondrocyte Implantation in Patients 45 Years or Older

Abstract

Background Autologous chondrocyte implantation (ACI) has become an accepted option for the treatment of chondral defects in carefully selected patients. Current recommendations limit this procedure to younger patients, as insufficient data are available to conclusively evaluate outcomes in patients older than 45 years. Hypothesis Cartilage repair with ACI in patients older than 45 years results in substantially different outcomes than those previously reported for younger age groups. Study Design Case series; Level of evidence, 4. Methods This prospective cohort study reviewed patients 45 years of age at the time of treatment with ACI. The clinical evaluation included a patient satisfaction questionnaire and four validated rating scales: Short Form-36, Modified Cincinnati Rating Scale, WOMAC (Western Ontario and McMaster Universities) Osteoarthritis Index, and the Knee Society Score. Results A total of 56 patients 45 years of age were treated with ACI. The average patient age at index surgery was 48.6 years (range, 45–60 years). The minimum follow-up was 2 years (range, 2–11 years; mean, 4.7 years). The cohort included 36 men and 20 women. The mean transplant size was 4.7 cm2 per defect (range, 1–15.0 cm2) and 9.8 cm2 per knee (range, 2.5–31.6 cm2). Twenty-eight patients (50%) underwent concomitant osteotomies to address malalignment. There were 8 failures (14%); 6 of 15 (40%) in patients receiving workers’ compensation (WC) and 2 of 41 (4.9%) in non-WC patients. Additional arthroscopic surgical procedures were required in 24 patients (43%) for periosteal-related problems and adhesions; 88% of these patients experienced lasting improvement. At their latest available follow-up, 72% of patients rated themselves as good or excellent, 78% felt improved, and 81 % would again choose ACI as a treatment option. Conclusion Our results showed a failure rate of ACI in older patients that is comparable with rates reported in younger patient groups. The procedure is associated with a substantial rate of reoperations, mostly for the arthroscopic treatment of graft hypertrophy, similar to that in younger patients.