Vascular Considerations in Foot and Ankle Free Tissue Transfer: Analysis of 231 Free Flaps

SLR - May 2016 - Lisa Grant-McDonald, DPM

Reference: Cho EH, Garcia RM, Pien I, Kuchibhatla M, Levinson H, Erdmann D, Levin LS, Hollenbeck ST. Vascular Considerations in Foot and Ankle Free Tissue Transfer: Analysis of 231 Free Flaps. Microsurgery 2015 Mar 23.

Reviewed By: Lisa Grant-McDonald, DPM
Residency Program: Western Pennsylvania Hospital Foot & Ankle Institute, Pittsburgh, PA

Podiatric Relevance: Foot and ankle soft tissue free flaps present challenging obstacles due to the unique functional demands of this anatomic location. Soft tissue reconstruction of the lower extremity is heavily reliant on the local blood supply. Pedal flaps have nearly 4-20 percent failure rate, which is much higher than head and neck reconstruction, which has been related to peripheral vascular disease. The below study is significant to the foot and ankle provider in that it gives appropriate expectation for soft tissue reconstructions of the foot and ankle.

Methods: A retrospective chart review was performed of patients who underwent free flaps at a single institution, performed by four different surgeons. Patient demographics, wound etiology, initial defect size, pre-operative vascular evaluation, flap survival, post-operative complications and platelet count were all recorded. Flap failure was categorized as intraoperative, or post-operative and as partial (<50 percent) or complete. Multivariate analysis was used to determine independent predictors of surgical outcomes.

Results: A total of 231 foot and ankle free flaps were performed on 225 people. Fifteen percent of patients enrolled were diabetic, 37 percent of which demonstrated pre-operative ischemia. Overall flap failure rate was 12 percent, 2 percent of flaps failed intraoperative and 10 percent post-operatively. Foot ischemia and failure was higher in patients who had pre-operative angiography or an abnormal vascular physical exam. Complications were not statistically different between multivessel occlusion and single vessel occlusion (p=1.00). Additionally, complications were not different between anastomosis of occluded vessel and non-diseased vessels. Patients who underwent vascular intervention did have significantly greater risk of failure.  

Conclusions: Free tissue transfers performed on patients with diabetes, chronic ulceration and elevated platelets are at an increased risk of procedure failure. Within these restrictions however, very few free tissues result in postoperative ischemia.