Approach to management of nerve gaps in peripheral nerve injuries

Published:January 20, 2022DOI:


      • Nerve gaps are broadly categorized into 3 groups depending upon the length of the gap between proximal and distal ends – less than one cm, upto five cm and longer than five cm.
      • A tension-free good nerve coaptation is usually achieved in gaps less than 1 cm and leads to good functional outcome provided the patient is not an elderly and presents within 6 months from time since injury.
      • Repair under tension causes neural ischemia resulting in poor functional outcome, pain and neuroma formation. So, autologous nerve grafting is the procedure of choice for nerve gaps up to 5 cm. Other options are cellular and acellular allografts and nerve conduits.
      • For longer nerve gap (more than 5 cm), autologous vascularized nerve grafts (VNGs) are used and in cases of unavailable proximal stump, nerve transfers and end-to-side neurorrhaphy are the useful options.
      • Electrodiagnostic studies are useful only when done 3–4 weeks after the injury conducted for motor and sensory nerves for both the limbs as to compare the values with that of normal side.
      • Researchers working in the areas of nerve injuries and regeneration are mainly targeting the different phases of the neural regeneration which comprises of two categories: strategies resulting in enhancement of axonal regeneration and process that shorten the denervation time.
      • The major factors to guide the clinical decision are the types of injury, patients’ age and duration of injury, the available options and the surgeon preferences and expertise.


      Peripheral nerve injuries (PNI) are a major clinical problem. In general, PNI results from motor vehicle accidents, lacerations with sharp objects, penetrating trauma (gunshot wounds) and stretching or crushing trauma and fractures. They can result in significant morbidity, including motor and/or sensory loss, which can affect significantly the life of the patient. Currently, the standard surgical technique for complete nerve transection is end-to-end neurorrhaphy. Unfortunately, there is segmental loss of the nerve trunk in some cases where nerve mobilization may permit end-to-end neurorrhaphy if the gap is less than 1 cm. When the nerve gap exceeds 1 cm, autologous nerve grafting is the gold standard of treatment. But in light of limited availability and concerned donor site morbidity, other techniques have been used: vascularized nerve grafts, cellular and acellular allografts, nerve conduits, nerve transfers and end-to-side neurorrhaphy. This review intends to present an overview of the literature on the applications of these techniques in repair of peripheral nerve injuries. This article also focuses on preoperative assessment, surgical timing, available options and future perspectives.


      PNI (Peripheral nerve injuries), NCS (Nerve conduction studies), EMG (Electromyography)


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