The patellofemoral joint can be a particularly challenging environment for treating chondral defects, due to the high loads acting on its surface. Among the different available surgical options for treatment of chondral defects, the single-stage AMIC procedure was performed, which uses a collagen I/III membrane to enhance bone-marrow stimulation. In order to ascertain the effectiveness of AMIC in treating chondral lesions, an ongoing registry has been established in order to record patient data and outcomes. Here, we evaluated the effectiveness of AMIC for patellar chondral lesions.
All data were retrieved from a multisite, prospective registry that recorded demographic data and outcomes for patients who had undergone surgical repair of patellar, chondral defects. In total, 63 patients from 5 surgeons were included in the analysis. All defects had been classified as Outerbridge III or IV and were treated with the 1-stage AMIC procedure.
The mean lesion size was 3.2 ± 1.6 cm2. The most common surgical approach was mini-open while the most common fixation was via fibrin glue. Follow-up visits were conducted as part of the standard of care at each site. The figure below shows a significant improvement in the Lysholm
follow-up up to 10 years. Likewise, a significant decrease in pain VAS was noted at all post-operative timepoints (p<0.01). With regard to physical activity, the sports-recreation score showed a significant improvement, and at the latest follow-up was still significantly higher than the pre-operative score (P<0.05).
The data from this study demonstrate that the 1-stage AMIC procedure is an effective treatment for retropatellar cartilage defects, and provides positive results, as demonstrated by decreased pain and improved function of the patients. Importantly, these improvements were maintained up to 10 years after surgery.