Donor Site Morbidity and Functional Status Following Medial Femoral Condyle Flap Harvest.

BACKGROUND: The medial femoral condyle (MFC) 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. Herein, we report the postoperative outcomes and analyze the impact of increasing the size of the flap on the knee donor site morbidity.

METHODS: A retrospective chart review of patients who underwent MFC flap between 2001 and 2012 at our institution was done. The size of the flap was stratified, based on the largest dimension, into 3 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: the Lower Extremity Functional Scale (LEFS) questionnaire. A univariate logistic regression analysis was done, and results were analyzed.

RESULTS: A total of 75 patients were identified. Average age was 29.5 ± 15.2 years (range: 14-72). Average follow-up time was 13 months postoperatively. Overall Complication rate was 18.6%. Donor site paresthesia in the saphenous nerve distribution was the most common complication. Increasing size of the flap did result in a significant elevation in complication risk (p<.05). A total of 47 patients completed the LEFS questionnaire. Average LEFS score was 72.12 ± 14.18 (range 28-80). 51% (n=24) scored 80 points, indicating a normal level of function on average.

CONCLUSIONS: The MFC flap has overall acceptable donor site morbidity with good level of function post-operatively. Larger flaps are associated with greater number of complications.