Fate of Combat Nerve Injury

Objective: Assess a cohort of combat-related type III open tibia fractures with peripheral nerve injury to determine the injury mechanism and likelihood for recovery or improvement in nerve function. Design: Retrospective study. Setting: Three military medical centers. Patients and Participants: Out of a study cohort of 213 type III open tibia fractures, 32 fractures (in 32 patients) with a total of 43 peripheral nerve injuries (peroneal or tibial) distal to the popliteal fossa met inclusion criteria and were available for follow-up at an average of 20 months (range, 2-48 months). Main Outcome Measurements: Clinical assessment of motor and sensory nerve improvement. Results: There was a 22% incidence of peripheral nerve injury in the study cohort. At an average follow-up of 20 months (range, 2-48 months), 89% of injured motor nerves were functional, whereas the injured sensory nerves had function in 93%. Fifty percent and 27% of motor and sensory injuries demonstrated improvement, respectively (P = 0.043). With the numbers available, there was no difference in motor or sensory improvement based on mechanism of injury, fracture severity or location, soft tissue injury, or specific nerve injured. In the subset of patients with an initially impaired sensory examination, full improvement was related to fracture location (P = 0.0164). Conclusions: Type III open tibia fractures sustained in combat are associated with a 22% incidence of peripheral nerve injury, and the majority are due to multiple projectile penetrating injury. Despite the severe nature of these injuries, the vast majority of patients had a functional nerve status by an average of 2-year follow-up. Based on these findings, discussions regarding limb salvage and amputation should not be overly influenced by the patient's peripheral nerve status.