Multistage microsurgical reconstruction after catastrophic shark attack: Vascularized ulnar nerve grafting for a large segmental sciatic nerve defect.

We present a 48-year-old woman who sustained life threatening polytrauma from a shark attack in New Caledonia, including posterior trunk and thigh crush-avulsion, bilateral upper-limb amputations and a 16 cm segmental sciatic nerve defect. Staged reconstruction included a free latissimus dorsi (LD) flap to the posterior thigh, a vascularized ulnar nerve graft (VUNG) for sciatic repair, a neurotized anterolateral thigh (ALT) flap for sensate hand coverage, toe-to-thumb transfer and targeted muscle reinnervation (TMR). This approach achieved functional independence and quality of life restoration. This is the first reported use of a VUNG for large segmental sciatic nerve reconstruction.