Introduction: Our goals were to observe and evaluate the outcome of pain reduction and long length acellular cadaver allograft use in the repair of sciatic nerve injuries of patients injured in recent military conflicts. Traumatic injury to the sciatic nerve is associated with widespread soft tissue and bone injuries, significant neurologic impairment, severe neuritic pain, and a prolonged recovery.

Methods: Retrospective review of 5137 combat related extremity injuries, 2007-2013, with 13 having sciatic nerve injury without amputation of the affected side.

Results: Thirteen patients were identified with combat-related sciatic nerve injuries, all were male, mean age was 28. The mechanisms of injury were 9 gunshot wounds (69%), 2 rocket propelled grenade blasts (15%) and 2 improvised explosive device blasts (15%). Three patients (23%) were found to have a neuroma in continuity, and required only neurolysis. Eight, patients (53%) with nerve transections and neuroma formation had long length (5-7 cm) cadaver allograft grafts placed, one patient had a sural nerve autograft (5 cm), and 1 patient underwent end to end direct nerve repair. Five (38%) patients underwent surgery 21 to 30 days after the time of injury (early), and eight (61%) patients had surgery greater than 150 days after injury (standard). There was no difference in the amount of nerve resection between the early and late groups, and both had equivalent pain and narcotic use reductions at 6 weeks and 6 months. There were no graft infections or rejections.

Conclusions: Traditional teaching is to delay nerve repair for at least six months to provide opportunity for the damage to the injured nerve to fully declare itself. Our experience suggests that combat related sciatic nerve injuries can be operated on 21-30 days post-injury, with benefit toward reduction of neuritic pain, and long-length cadaveric allografts may be placed without infection/rejection.

Patient Care: There is limited data that describes the treatment of these significant and devastating nerve injuries. The significance of severe neuritic pain after sciatic nerve injury should not be underestimated. We hope our small study sheds light on a relatively poorly understood area of patient care, and inspires future study on the timing (early vs. deliberately delayed) of nerve repair and on the potential of emerging cadaveric nerve allograft products.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Briefly describe the epidemiology of wartime peripheral nerve injuries 2) Discuss the significance of neuritic pain in those suffering sciatic nerve injury 3) Describe the general characteristics of cadaveric peripheral nerve allograft 4) Discuss the arguments, for and against, regarding the consideration of surgery to manage neuritic pain after trauma to a major peripheral nerve

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