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Health condition · Clinically reviewed

Peripheral nerve injuries, from mild conduction block to complete division.

Not every nerve injury needs surgery - but some do, and timing matters. A clear grading system and a stepped plan get you to the right answer quickly.

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Why trust this guide

  • 01

    Clinically reviewed

    Written by our editorial team and reviewed by a registered UK clinician before publication.

  • 02

    Sourced from guidance

    Checked against BSSH, NICE and peer-reviewed sources you can see at the end.

  • 03

    Current for 2026

    Reflects modern UK hand and peripheral nerve surgery practice, including timing of repair and rehabilitation.

Key facts

Peripheral nerve injuries at a glance.

The essentials, in plain English - what it is, how it's graded, and how it's managed under UK guidance today.

  • What it is

    Traumatic damage to a peripheral nerve from laceration, stretch or traction, compression, or crush - disrupting sensation, movement or both.

  • Seddon grades

    Neurapraxia (mildest, conduction block), axonotmesis (axon damage, sheath intact) and neurotmesis (complete division, needs surgery).

  • Regeneration rate

    Where axons can regrow, they do so at roughly 1mm a day - recovery is measured in months, not weeks.

  • Classic patterns

    Wrist drop points to radial nerve injury; a claw hand points to ulnar nerve injury at the wrist or elbow.

  • Repair window

    Complete division (neurotmesis) is best repaired within days to a few weeks of injury - outcomes worsen the longer repair is delayed.

  • Investigations

    Nerve conduction studies and EMG grade severity; MRI or ultrasound shows structural continuity of the nerve itself.

Why this guide matters

Grading the injury changes the whole plan.

Peripheral nerve injuries range from a bruise that settles on its own to a complete division that only recovers with surgery. The three points below shape everything else on this page.

  • Not all nerve injuries are equal

    The Seddon classification - neurapraxia, axonotmesis, neurotmesis - sets expectations for recovery and decides whether surgery is even on the table.

  • Timing drives outcome

    A complete division repaired within days to weeks does far better than one found and fixed months later - early referral genuinely matters.

  • Regeneration is slow but real

    Where the sheath survives, nerves regrow at roughly 1mm a day - patience and protection give that process the best chance.

How the diagnosis is made

From the injury to a clear plan.

The steps a UK hand surgeon or peripheral nerve specialist will normally follow, in order - so you know what to expect and why.

  1. 01

    Assessing

    History and mechanism

    How the injury happened - a clean laceration, a stretch or traction injury, a crush, or prolonged compression - shapes everything that follows.

  2. 02

    Assessing

    Sensory and motor examination

    Mapping numbness and weakness against known nerve territories to identify which nerve, and at what level, is affected.

  3. 03

    Assessing

    Seddon classification

    Clinical findings are used to estimate neurapraxia, axonotmesis or neurotmesis - this drives the urgency of what happens next.

  4. 04

    Confirming

    Nerve conduction studies and EMG

    Useful for grading severity and tracking recovery over time, though very early studies can underestimate how severe the injury really is.

  5. 05

    Confirming

    MRI or ultrasound imaging

    Structural imaging shows whether the nerve is in continuity, thickened, or completely divided - particularly useful before surgery.

  6. 06

    Preparing

    Specialist referral

    Plastic surgery, orthopaedic hand surgery or peripheral nerve surgery input for anything beyond a straightforward neurapraxia.

  7. 07

    Preparing

    Decision on surgical exploration

    Confirmed or suspected complete division is explored and repaired promptly - ideally within days to a few weeks of the original injury.

Typical timeline: assessment within days, a repair decision within weeks.

Symptoms

What a nerve injury actually looks like.

The pattern of numbness, weakness and pain depends entirely on which nerve is hurt and how badly. And the features that mean it's time to escalate.

  • Numbness and sensory loss

    Loss of feeling in the specific skin territory the injured nerve supplies - often the first symptom people notice.

  • Motor weakness or paralysis

    The muscles that nerve supplies lose power or stop working altogether, depending on how severe the injury is.

  • Wrist drop

    Inability to extend the wrist and fingers - the classic sign of a radial nerve injury, often after a humeral fracture.

  • Claw hand

    Hyperextended knuckles with clawed fingers - the classic sign of ulnar nerve injury at the elbow or wrist.

  • Neuropathic pain

    Burning, shooting or electric-shock-like pain in the nerve distribution, sometimes out of proportion to the visible injury.

  • Muscle wasting

    Visible thinning of denervated muscle over weeks to months when a nerve injury goes unrepaired or recovery stalls.

  • Reduced or absent reflexes

    Reflexes that rely on the injured nerve become sluggish or disappear, helping localise the level of damage.

  • Red flag - suspected complete division

    A penetrating wound with immediate, complete loss of sensation and movement suggests neurotmesis and needs urgent surgical assessment.

Treatment

How nerve injuries are treated in the UK.

Observation for the mildest injuries, monitored regeneration for many, and prompt surgical repair for complete division.

  • Observation for neurapraxia

    The mildest injury - a temporary conduction block that typically recovers spontaneously over days to weeks with no surgery needed.

  • Monitoring for axonotmesis

    The axon is damaged but the surrounding sheath survives, so many cases are managed conservatively while regeneration is tracked clinically and electrically.

  • Surgical exploration and repair

    Complete division (neurotmesis) needs formal surgical repair - ideally within days to a few weeks for the best chance of useful recovery.

  • Nerve grafting

    Where a gap is too large to close directly, a graft bridges it - donor nerve or a conduit, chosen according to the gap and the nerve involved.

  • Splinting

    Protects denervated muscles from overstretching and prevents joint contractures while the nerve recovers, whether repaired or observed.

  • Physiotherapy and occupational therapy

    Runs throughout recovery - maintaining range of movement, re-educating muscles as they reinnervate, and building functional hand or limb use.

  • Neuropathic pain management

    Medication such as gabapentinoids or amitriptyline, alongside physical strategies, for the burning or shooting pain that can accompany nerve injury.

  • Psychological support

    Recovery can be slow and functionally limiting - psychological input helps with the emotional load of a prolonged rehabilitation journey.

What this guide is based on

The sources behind every claim on this page.

UK national guidance and specialist society standards, current at the time of last review.

Key references

Guidelines and standards we relied on.

A quiet reminder

This guide is for information, not medical advice.

Your GP or hand surgeon knows your injury and history and can tell you which parts apply to you. If in doubt, get seen.

  • British Society for Surgery of the Hand (BSSH). Guidance on peripheral nerve injury management.

  • NICE. Assessment and early management of major trauma (relevant nerve injury sections).

  • British Association of Plastic, Reconstructive and Aesthetic Surgeons (BAPRAS). Peripheral nerve repair standards.

  • Association of British Neurologists. Guidance on nerve conduction studies and EMG interpretation.

Red flags

When a nerve injury needs urgent attention.

Most nerve injuries can be assessed and managed on a routine timescale. These are the situations that can't wait.

  • Suspected complete nerve division

    A penetrating injury with immediate, complete sensory and motor loss needs urgent surgical assessment - delay worsens outcomes.

  • Progressive weakness or numbness

    Worsening deficit after the initial injury suggests ongoing compression or a missed diagnosis and needs prompt reassessment.

  • Signs of compartment syndrome

    Severe pain, tense swelling and pain on passive stretch alongside a nerve injury is a surgical emergency, not something to observe.

  • Associated vascular compromise

    A cold, pale or pulseless limb alongside a nerve injury points to combined vascular damage needing immediate specialist care.

  • No recovery within the expected window

    Regeneration proceeds at roughly 1mm a day - if recovery stalls well beyond that estimate, re-referral for imaging or re-exploration is warranted.

  • Worsening localised pain or a lump

    A painful, tender swelling at the injury site can indicate a neuroma and deserves specialist review.

  • Features of complex regional pain syndrome

    Disproportionate pain with skin, temperature or sweating changes in the limb needs early pain-team involvement.

  • Delayed presentation

    Presenting weeks or months after the original injury narrows the surgical window and needs an urgent specialist opinion rather than routine referral.

  • Significant psychological distress

    Low mood, anxiety or despair over a slow or incomplete recovery deserves the same attention as the physical injury.

Living with it

A slow recovery, with a clear ladder.

Four things that make the biggest difference through recovery - patience with regeneration, protecting the limb, sticking with therapy and asking for support.

A quiet reminder

Slow progress is still progress.

Nerve recovery is measured in millimetres a day - steady rehabilitation over months does more than impatience ever will.

  1. 01 Patience

    Regeneration is slow

    Nerves regrow at roughly 1mm a day - recovery from a proximal injury can genuinely take the best part of a year.

  2. 02 Protect

    Splint and protect

    A denervated limb loses protective sensation - splinting guards against overstretch, burns and pressure injury while nerves recover.

  3. 03 Rehab

    Keep up therapy

    Physiotherapy and occupational therapy through the whole recovery keep joints supple and retrain muscles as the nerve reconnects.

  4. 04 Support

    Ask for psychological support

    A long, uncertain recovery takes a toll - support is available and asking for it early makes the whole process more manageable.

Frequently asked

Everything we get asked about nerve injuries.

Quick answers on grading, wrist drop and claw hand, healing time and when surgery is needed.

  • What is a peripheral nerve injury?

    Traumatic damage to a nerve outside the brain and spinal cord, from a laceration, stretch or traction injury, compression, or crush. Severity is graded using the Seddon classification - neurapraxia, axonotmesis or neurotmesis.

  • What is the difference between neurapraxia, axonotmesis and neurotmesis?

    Neurapraxia is the mildest - a temporary conduction block that usually recovers on its own. Axonotmesis is axon damage with the surrounding sheath intact, giving potential for regeneration. Neurotmesis is complete division of the nerve, which needs surgical repair.

  • Why do wrist drop and claw hand happen?

    Wrist drop follows radial nerve injury, which normally powers wrist and finger extension. Claw hand follows ulnar nerve injury, which normally balances the small muscles of the hand - without it, the fingers hyperextend at the knuckles and claw at the tips.

  • How quickly do nerves heal?

    Where regeneration is possible, axons regrow at roughly 1mm a day. That means recovery from an injury near the shoulder can take many months, while an injury close to the muscle it supplies recovers much faster.

  • When is surgery needed?

    Confirmed or strongly suspected complete division (neurotmesis) needs surgical exploration and repair, ideally within days to a few weeks of the injury. Nerve grafting is used when the gap between the two ends is too large to close directly.

  • What tests confirm the diagnosis?

    Clinical examination identifies the nerve and injury pattern. Nerve conduction studies and EMG grade severity and track recovery, though very early tests can underestimate the damage. MRI or ultrasound assesses the physical continuity of the nerve.

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