In the management of traumatic peripheral nerve injuries, the severity or degree of injury dictates the decision making between surgical management versus conservative management and serial examination. This review explores some of the recent literature, specifically addressing recent basic science advances in end-to-side and reverse end-to-side recovery, Schwann cell migration, and neuropathic pain. The management of nerve gaps, including the use of nerve conduits and acellularized nerve allografts, is examined. Current commonly performed nerve transfers are detailed with focus on both motor and sensory nerve transfers, their indications, and a basic overview of selected surgical techniques.
Peripheral nerve reconstruction continues to evolve and expand with the ongoing improvement in our understanding of internal nerve topography, advances in microsurgical technique, and current basic science and clinical research pertaining to nerve injury and repair.
An understanding of the classification of nerve injury, as well as the numerous factors that influence recovery, is critical in the management of traumatic peripheral nerve injuries ( Table 1 ). Multiple factors influence nerve recovery, including patient age, time elapsed since injury, proximity of nerve injury, presence of a nerve gap, associated vascular or soft tissue injuries, and mechanism of injury. The severity or degree of injury dictates the decision making between surgical management (fourth-degree and fifth-degree injuries) versus conservative management and serial examination (first-degree, second-degree, and third-degree).
| Degree of Injury | Tinel Sign Present | Recovery | Rate of Recovery | Surgical Procedure | |
|---|---|---|---|---|---|
| I | Neurapraxia | No | Complete | Up to 12 wk | None |
| II | Axonotmesis | Yes | Complete | 2.5 cm (1 inch) per mo | None |
| III | Yes | Varies a | 2.5 cm (1 inch) per mo | None or neurolysis | |
| IV | Neuroma in continuity | Yes, but no advancement | None | None | Nerve repair, graft, or transfer |
| V | Neurotmesis | Yes, but no advancement | None | None | Nerve repair, graft, or transfer |
| VI | Mixed injury (I to V) | Some fascicles (II, III) | Some fascicles (II, III) | Depends on degree of injury (I–V) | Neurolysis, nerve repair, graft, or transfer |
a Recovery can vary from excellent to poor depending on the amount of scarring and the sensory versus motor axon misdirection to target receptors.
This review explores some of the recent literature as it relates to current techniques, debates, and advances in nerve reconstruction of the hand and upper extremity. Specifically addressed are the recent basic science advances in end-to-side and reverse end-to-side recovery, Schwann cell migration, and neuropathic pain. The management of nerve gaps, including the use of nerve conduits and acellularized nerve allografts, is examined. Current commonly performed nerve transfers are detailed with focus on both motor and sensory nerve transfers, their indications, and a basic overview of selected surgical techniques.
Management of nerve gaps
The optimal method of nerve reconstruction is prompt, tension-free, primary anatomic end-to-end neurorrhaphy. Animal studies have shown that across every coaptation site a percentage of nerve fibers are lost, resulting in fewer nerve axons reaching the target organ. It is also important to consider that excessive tension has been shown to significantly impair regeneration across a nerve repair by causing a reduction in microvascular flow and an increase in scarring. If a truly tension-free repair is not possible, another method must be used to bridge the gap ( Table 2 ).
Related posts:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
