Treatment of Focal Chondral Lesions in the Patellofemoral Joint with Collagen Membrane: Clinical and Functional Outcomes in a Two-Year Follow-Up

Objective To evaluate the clinical and functional outcomes of patients undergoing surgical treatment to repair focal chondral lesions in the patella and trochlea using the autologous matrix-induced chondrogenesis (AMIC) technique after a minimum follow-up of 2 years.Methods A total of 24 patients (25 knees) with a mean age of 39.6 +/- 4.7 years underwent the patellofemoral AMIC technique and evaluation over a mean follow-up of 3.64 +/- 0.65 years. We collected data on patient factors, lesion morphology, and patient-reported outcome measures, including the International Knee Documentation Committee (IKDC), Tegner, Kujala, Fulkerson, and Lysholm scores, as well as the Visual Analog Scale (VAS).Results Male subjects accounted for 76% of the sample. The mean defect size of the chondral lesions was of 1.99 +/- 0.36 cm (2) . All defects were of grade IV according to the Outerbridge classification. At the last follow-up, patients showed the following mean increases in the scores: Kujala - from 61.9 to 87.9; IKDC -from 51.3 to 83.6; Lysholm -from 64.0 to 88.4; Tegner -from 4.04 to 5.12; Fulkerson -from 60.2 to 89.3; and VAS - from 5.6 to 1.24. All results were statistically significant ( p < 0.05).Conclusion The AMIC technique is a safe, effective, and feasible method to treat symptomatic full-thickness chondral defects of the patellofemoral cartilage in properly-selected cases, and it resulted in clinical and functional improvement in all criteria under analysis.