Multiple defects, workers' comp may impact outcomes after ACI

WASHINGTON — New research presented here at the 27th Annual Meeting of the Arthroscopy Association of North America indicates that autologous chondrocyte implantation provides durable functional improvement and symptomatic relief.

The investigators also identified factors that may influence outcomes after 2 years.

Brian J. Cole, MD, and colleagues prospectively studied 137 patients that he treated with autologous chondrocyte implantation (ACI) using Carticel autologous cultured chondrocytes (Genzyme) with a minimum 2-year follow-up. They discovered statistically significant differences between the preoperative and final postoperative scores on the Lysholm, Tegner, IKDC, KOOS and SF-12 scales and found that 75% of the patients were completely or mostly satisfied with the procedure.

He also found no significant difference in outcomes based on defect location or the type of prior procedure performed on the patients. However, patients who had multiple defects had significantly different KOOS quality-of-life and IKDC scores compared to the entire cohort.

In addition, patients with work-related injuries had lower scores on nearly every outcome measure compared to those with non-work-related injuries.

"This is a relatively large cohort of patients in a single center with greater than 4-year follow-up," Cole said during his presentation. "The results have proved to be durable and [demonstrate] symptomatic improvement. Multiple defects rather than defect location seem to negatively affect our outcome, as did the fact that these patients had a workers' compensation claim."

The study included patients with a mean age of 30 years and had an average follow-up of 4.3 years. Most of the patients had medial femoral condyle lesions, and the total defect area averaged 5.2cm².

"Our reoperation rate in general was approximately 30%, but 16% is what we believe to be related to the ACI," Cole said.

Those who underwent another surgery due to their ACI had the reoperation at an average of 27 months. There was a 5.7% failure rate, and the average time to revision among all patients was 43 months.

For more information:
Cole BJ, McNickle AG, L'Heureux DR, et al. Autologous chondrocyte implantation: Functional and symptomatic outcomes beyond two years. Paper #SS18. Presented at the 27th Annual Meeting of the Arthroscopy Association of North America. April 24-27, 2008. Washington.