Peripheral Nerve Injury:Post-surgical rehabilitationDr Andrew Yam MBBS, MRCS, MMed (Surg), FAMS (Hand Surgery)Hand and Peripheral Nerve Surgeon

Hand Surgery Associates www.handsurgerysingapore.com

Post-nerve repair Protect the repair!

◦ SPLINT for 2-3 weeks in position of minimal tension◦ Block movements that stretch nerve, allow those that

slacken nerve

Prevent adhesions◦ NERVE GLIDING exercises during and after period of

splinting

Monitor for recovery

Formal rehabilitation programme

Stages of RecoveryStage IDegeneration(First 2-3 weeks)

Wallerian degenerationLoss of nerve functionCortical rearrangement starts

Stages of RecoveryStage IDegeneration(First 2-3 weeks)

Wallerian degenerationLoss of nerve functionCortical rearrangement starts

Stage IIRegeneration(2-18 months depending on distance to target organ)

Axonal regeneration after successful repairChronic denervation changes, end-organ atrophyDecreased motor and sensory cortical representation

Stages of Recovery

Stage IDegeneration(First 2-3 weeks)

Wallerian degenerationLoss of nerve functionCortical rearrangement starts

Stage IIRegeneration(2-18 months depending on distance to target organ)

Axonal regeneration after successful repairChronic denervation changes, end-organ atrophyDecreased motor and sensory cortical representation

Stage IIIReinnervation and maturation(Up to 5 years)

Function returns but impaired due to denervation atrophy, immature and decreased axons and cortical representation

Increasing function with maturation and cortical reorganisation

Rehabilitation after Peripheral Nerve Injury

Surgical TherapySTAGE I(Degenerative stage)

DiagnosisAssess severityNerve repair/recon

Sensory and motor assessmentPrevent complications of denervationSensory re-education Pain control

Complications of denervation Stiffness

Injury and infection

Neuropathic pain syndromes

Abnormal joint postures due to imbalanced forces across joints joint contractures

Myostatic contracture

Tendon adhesions

Oedema- Dependent limb- Loss of muscle pump- Loss of sympathetic tone

Stiffness

PATIENTS TEND TO NEGLECT OR AVOID MOVING AND TOUCHING THE DENERVATED LIMB

Median and ulnar nerve – MCPJ extension and PIPJ flexion contracturesRadial nerve – flexion contracturesBrachial plexus – shoulder, elbow, wrist, finger contractures

Joint stiffness is a contraindication for tendon transfers

Reinnervated muscles will not overcome stiffness

ALL JOINTS MUST BE KEPT SUPPLE IN ANTICIPATION OF FUNCTIONAL RECOVERY BY REINNERVATION OR

MUSCLE TRANSFER

Management of joints post nerve injuryPassive mobilization through full range as early as possible

Patient education and compliance – prevent neglect

Splinting with caution in insensate hands

No heat therapy in insensate hands

Surgical release as necessary

Secondary injury and infection

Insensate limbs prone to serious injury - no withdrawal reflex

Paralyzed limbs cannot be moved out of danger

Neuropathic ulcers

Burns

Neglected cuts

Severe infection with delayed treatment

Preventing secondary injury and infection

Awareness of danger of insensate limb

Avoid exposure to hot, cold or sharp objects

Frequent inspection for injury

Keep flail limbs in sling

Avoid prolonged pressure including splints

Neuropathic Pain Most major nerve

injuries

Up to 80% of brachial plexus avulsion injuries

NEUROPATHIC PAIN MAY BE THE MOST CRIPPLING ASPECT OF

NERVE INJURY

CRPS Type IIAvulsion/deafferentation painNeurostenalgiaAbnormal perception of stimuli – allodynia, dysaesthesia

Pain management Pharmacological Physical Behavioural Psychological Surgical

AGGRESSIVE EARLY MULTI-MODALITY TREATMENT OF NEUROPATHIC PAIN IMPORTANT TO DECREASE RISK OF DEVELOPING CHRONIC PAIN

SYNDROME

Desensitisation Gate-control theory

Melzack

Non-painful stimulus◦ To border of hyperaesthetic

area◦ To territory of other nerves

in same dermatome◦ To adjacent dermatome

Gradual increase in intensity of stimulus

Sensory Re-education CORTICAL PLASTICITY Decreased afferent transmission to cortex decreased cortical

representation of denervated area

Early (immediate) re-education to maintain cortical representation

Substitute touch sense with visual or auditory

Rehabilitation after Peripheral Nerve Injury

Surgical TherapySTAGE I(Degenerative stage) Diagnosis

Assess severityNerve repair/recon

Prevent complications of denervationSensory re-education Pain management

STAGE II(Regeneration)

Manage contractures, adhesions and other complications of denervationMonitor recovery (advancing Tinel’s sign)

Adaptive techniquesAssistive devicesPain managementStrengthen and isolate donor muscles

PERIPHERAL NERVE INJURIES RARELY INCAPACITATE COMPLETELY!

Augmenting existing function Assistive devices and coping

strategies

Avoid inactivity and reinforcement of “helplessness”

Assistive devices

Training uninjured limb to compensate

Train to do things differently to compensate

Change of mindset - motivational talks, acceptance of limitation, hope for recovery, employment

Methods to augment existing function

ENCOURAGE USE OF THE INJURED LIMB AS MUCH AS POSSIBLE

Radial nerve – finger and wrist extension

Median nerve – thumb abduction/opposition

Ulnar nerve – claw hand correction

Assistive devices

Assistive devices

Radial nerve

Median nerve

Ulnar nerve

Upper type BPI Flail arm Gauntlet with attachments

Strengthening and Isolating Donor Muscles

All potential donor muscles for transfer identified

Physical exercises to increase strength

Visualisation of new function while activating donor muscle

Physical activity decreases neuropathic pain and increases sense of well-being

EARLY TRAINING OF DONOR MUSCLES FACILITATESRE-EDUCATION AFTER TRANSFER

Rehabilitation after Peripheral Nerve Injury

Surgical TherapySTAGE I(Degenerative stage) Diagnosis

Assess severityNerve repair/recon

Prevent complications of denervationSensory re-education Desensitisation

STAGE II(Regeneration)

Manage contractures, adhesions and other complications of denervationMonitor recovery (advancing Tinel’s sign)

Adaptive techniquesAssistive devicesDesensitisationStrengthen and isolate donor muscles

Stage III(Post-reinnervation or reconstruction)

Tendon transfersFunctioning free muscle

Protected mobilisationRe-training of transferrednerve or muscleStrengthening, dexterity

Graduated strengthening exercises - gravity eliminated exercises - resistance exercises - functional use and work hardening

Neuromuscular electrical stimulation

Biofeedback

Muscle strengthening and training

Graduated Strengthening Exercises

Gravity eliminated exercises for shoulder and elbowMuscle power M2-M3

Resistance training Work hardening with BTEMuscle power M3 and above

Neuromuscular Electrical Stimulation (NMES)

Surface electrodes stimulate reinnervated muscle end plates augmenting active contraction

High intensity, short duration

Beware of muscle fatigue and injury

Biofeedback Surface electrode EMGs

Visual/auditory feedback ◦ Increase contraction of

agonist muscles◦ Decrease contraction of

antagonists

Useful for managing co-contractions and training tendon/muscle transfers

Summary Intensive structured rehabilitation program is essential to

achieve good functional results after nerve injury and reconstruction

Rehabilitation starts immediately post-injury to minimize cortical reorganization and encourage ongoing use of the denervated upper limb

Program tailored to different stages of recovery Patient motivation is essential until reinnervation and

maturation (up to 2 YEARS for higher lesions, BPI) Pain management is vital – the patient will not use a painful

limb Emphasis on early return to function while

accepting limitations and learning to adapt

Thank You!