Impact of venous outflow tract on survival of osteocutaneous free fibula flaps for mandibular reconstruction: A 14-year review.

BACKGROUND: The principle reconstructive modality for segmental mandibulectomy defects is the osteocutaneous free fibula flap. Preoperative CT angiography has been recommended to assess the quality of arterial inflow to the flap and donor limb. However, the impact of the venous system on flap viability has not been explored. METHODS: A retrospective review of all patients undergoing free fibula flap mandible reconstruction was performed at a single tertiary cancer center from 2002 to 2015. Overall complications, including operative reexploration and total flap losses, were evaluated. RESULTS: One hundred seven patients underwent free fibula flap reconstruction of the mandible. Nine patients underwent multiple free flaps and were excluded from this study. Of the remaining 98 patients, 8 patients required operative exploration for microvascular compromise. All patients were found to have venous thrombosis. There were 3 total flaps losses with a salvage rate of 62.5% and overall flap survival of 96.9%. The size of the vena comitantes in the compromised flaps were significantly larger than those of the remaining patients (4.4 mm vs 3.1 mm; P < .0001). Although the total operative times were similar between the 2 groups (585.2 minutes vs 563.3 minutes), the ischemia time was significantly shorter in those cases that required operative takeback (76.5 minutes vs 104.0 minutes; P < .04). CONCLUSION: Venous thrombosis of free fibula flaps is more common than arterial thrombosis. Venous stasis in larger vena comitantes may be a contributing factor to microvascular compromise. Anticoagulation and/or handsewn anastomosis may be beneficial if the veins are larger than 4.0 mm in size.