Nerve repair, grafting, and nerve transfers

Until the late 18th century, it was felt that peripheral nerves did not regenerate after injury [1]. Since that time, tremendous advances have been made in our understanding of peripheral nerve injury and repair. The processes of nerve regeneration and target reinnervation are complex and involve multiple factors. Nerve regeneration does not begin if the cell body has not survived the initial injury or if it is unable to initiate regeneration. The distal nerve stump must then provide the appropriate environment to support regeneration. Finally, the regenerated axons must reach and reinnervate the appropriate target end-organs in a timely fashion. A thorough knowledge of peripheral nerve anatomy, physiology, and pathophysiology is critical to obtaining optimal results. Many additional factors influence the success of nerve repair or reconstruction. The timing of the repair, the level of the injury, the extent of the zone of injury, the technical skill of the surgeon, and the method of repair or reconstruction contribute to the functional outcome after nerve injury. This article reviews the principles and techniques of nerve repair and discusses the options to direct repair, including nerve grafts, conduits, end-to-side repair, and nerve-to-nerve transfers.