Donor-site morbidity and functional status following medial femoral condyle flap harvest

Background: The medial femoral condyle free vascularized bone flap is a valuable alternative to other types of vascularized bone grafts. The donor-site morbidity and functional outcomes after flap harvest have not been fully appreciated. The authors report the postoperative outcomes and analyze the impact of increasing the size of the flap on knee donor-site morbidity. Methods: A retrospective chart review of patients who underwent medial femoral condyle flap surgery between 2001 and 2012 at their institution was performed. The size of the flap was stratified, based on the largest dimension, into three groups. Demographics, outcomes, and complications related to the flap donor site were recorded and analyzed. Subsequently, functional status was assessed by administering a validated condition-specific measure. A univariate logistic regression analysis was performed, and results were analyzed. Results: A total of 75 patients were identified. Average age was 29.5 ± 15.2 years. Average follow-up time was 13 months. The overall complication rate was 18.6 percent. Paresthesia in the saphenous nerve distribution was the most common complication. Increasing the size of the flap resulted in a significant elevation in complication risk (p < 0.05). A total of 47 patients completed the Lower Extremity Functional Scale questionnaire. The average Lower Extremity Functional Scale score was 72.12 ± 14.18. Fifty-one percent (n = 24) scored 80 points, indicating a normal level of function on average. Conclusions: The medial femoral condyle flap has overall acceptable donor-site morbidity, with a good level of function postoperatively. Larger flaps are associated with a greater number of complications.