Factors Affecting Bone Fusion in Mandibular Reconstruction With Vascularized Free Fibula Flap

Reconstruction of mandibular defects with free fibula flaps was described 3 decades ago. However, scant literature exists regarding their bony fusion. A retrospective cohort study was performed to determine what factors influence the amount of osseous fusion at various osteotomy sites (condyle, angle, body, parasymphysis, and midsagittal). A total of 30 patients (12 females and 18 males) with an average mean age of 49.7 years (SD: 22.1, range: 11-82) were included. There were 80 osteotomy locations, with 3 margins each, for 240 total fusion ratings and an average fusion of 3.70 (SD: 1.08) on a 1 to 5 scale. The amount of fusion at osteotomy sites was significantly association with sex (female 3.96 versus male 3.51, P = 0.001), age (r = -0.23, P < 0.001), postoperative (radiation therapy: 3.21 versus no-radiation therapy 3.76, P = 0.018), number of fibula segments (P < 0.001), etiology (P < 0.001), and mandibular defect classification (P < 0.001). No significant difference was identified between the amount of fusion and osteotomy type (fibula-fibula-fibula-mandible), location (P = 0.140), or margin (P = 0.612). These factors could be important predictors for nonunion and risk of postoperative fracture.