Failure of salvage therapies in radiation-induced necrosis of a free fibula flap: a case report

Introduction and importance: Osteoradionecrosis (ORN) of a free fibula flap following mandibular reconstruction is a rare but severe complication in head and neck cancer survivors. Despite advances in microvascular reconstruction and radiotherapy protocols, late-onset ORN remains a therapeutic challenge with limited evidence guiding management. Case presentation: A 53-year-old male smoker presented 2 years post-resection of pT4aN1M0 (Stage IVA) oral floor squamous cell carcinoma, having undergone mandibular reconstruction with a free fibula flap and adjuvant radiotherapy (66 Gy). Routine CT surveillance at 1 year revealed asymptomatic radiation-induced changes in the flap. By 2 years, he developed pain, trismus, swelling, titanium bar extrusion, and large sequestra. Biopsy confirmed ORN. Initial conservative therapy - including antibiotics, NSAIDs, and pentoxifylline with α-tocopherol - failed. Subsequent sequestrectomy provided only transient relief, with recurrent sequestra and persistent symptoms. Ultimately, the fibula flap was completely removed, and the patient declined a second free flap; reconstruction was completed with a pectoralis major myocutaneous flap, resulting in an uneventful recovery. Clinical discussion: This case underscores the aggressive nature of ORN in vascularized bone flaps and the limitations of conventional salvage therapies. Conclusions: When conservative and surgical salvage fail, prompt flap excision and alternative reconstruction may be necessary. This case provides longitudinal, image-supported documentation of sequential treatment failure and patient-driven deviation from standard free flap salvage.