Free fibula mandible reconstruction for osteoradionecrosis is more challenging than for primary cancer.

[INTRODUCTION] Osteoradionecrosis (ORN) of the mandible is an unfortunate potential sequela of radiotherapy for head and neck cancer. In advanced cases of ORN, mandibulectomy, and free fibula flap reconstruction are required. We hypothesized that patients undergoing fibula free flap reconstruction and mandibulectomy for ORN pose unique challenges and experience more complications than patients undergoing fibula free flaps after oncologic mandibulectomy.

[METHODS] After IRB approval, we created a database of all free fibula flaps for mandible reconstruction from April 2005 through February 2019. Medical records were retrospectively reviewed for patient and surgical characteristics and postoperative outcomes.

[RESULTS] Four-hundred seventy-nine patients met the inclusion criteria (168 ORN vs. 311 non-ORN patients). Propensity-matching was performed based on age, BMI, smoking status, preoperative chemotherapy, and virtual surgery planning use, which yielded 159 patients in each group. ORN patients received more double-skin-island fibula flaps than non-OR patients (20.8% vs. 5.7%, p < 0.001). Recipient artery other than the facial artery was utilized more commonly in ORN patients (42.1% vs. 17.0%, p < 0.001). In the unmatched cohort, ORN patients had higher rates of delayed wound healing (26.2% vs. 16.8%, p = 0.01) and surgical site infections (21.4% vs. 13.2%, p = 0.02). Rates of flap loss, return to the operating room, hematoma, operative time, and length of stay were similar between the groups. On logistic regression analysis, osteoradionecrosis was an independent risk factor for delayed wound healing.

[CONCLUSION] Based on these data, mandibular reconstruction with fibula flaps for osteoradionecrosis appears more complicated than mandible reconstruction following de novo cancer resection. Surgeons should anticipate employing two skin islands for intraoral and extraoral resurfacing, utilizing unconventional recipient vessels, and managing the delayed wound healing that ensues more commonly than non-ORN patients.