Peripheral nerves injuries – Upper Limb

 

Peripheral nerves disorders

Look

(inspection)

Feel

(palpation)

Move

Measure / special tests

  • Lump (Tumor – Neuroma)
  • Wound / scar
  • Deformity
  • Motor effects (Active movement – Wasting – Reflexes)
  • Trophic changes (Ulceration)
  • Vasomotor effects (Skin color)
  • Temperature
  • Tenderness
  • Lump
  • Wound / scar
  • Nerve
  • Sensory effects
  • Trophic changes (Ulcer)
  • Vasomotor effects (Temperature – Peripheral pulsations)
  • Sudomotor effects (Sweating)
  • Active (1st)
  • Passive
  • Against resistance
  • Full range vs. limited rang
  • Painful vs. painless
Tinel’s test

Examination of peripheral circulation

 

Questions to be answered after examination

  • Is there a nerve injury?
  • Which nerve?
  • What is the Level of injury? (Site of the scar or the wound – Sensory effects – Motor effects – Deformity – Wasting)
  • What is the form of injury? (Neurapraxia – axonotmesis – neurotmesis)
  • Is it complete or partial?
  • What is duration of injury?
  • Is there any associated injuries?
  • What is the cause?

Description of nerve injury

  • Site of injury
  • Special form of injuries
  • Sensory effects
  • Motor effects
  • Deformity
Branches of the main nerves in upper limb
Site

Median nerve

Ulnar nerve

Radial nerve

Axilla
  • Long and medial head of triceps
  • Posterior Cutaneous nerve of arm
Arm In spiral groove

  • Medial and lateral head of triceps
  • Anconeus
  • Lower lateral Cutaneous of arm
  • Posterior cutaneous of forearm

In lateral side of the arm

  • Brachioradialis
  • Extensor carpi radialis longus
  • Lateral 1/2 of brachialis
Forearm In cubital fossa

  • Pronator teres
  • Flexor carpi radialis
  • Palmaris longus
  • Flexor digitorum superficialis

Anterior interosseos

  • Flexor polices longus
  • Pronator quadrates
  • Lateral 1\2 of flexor digitorum profundus

Palmar Cutaneous

Near the elbow

  • Flexor carpi ulnaris
  • Medial 1/2 of flexor digitorum profundus

Near the wrist

  • Dorsal Cutaneous
  • Palmar Cutaneous
Posterior interosseous nerve

All extensors of forearm

Except

  • Brachioradialis
  • Extensor carpi radialis longus
  • Extensor carpi radialis brevis

In cubital fossa

  • Supinator
  • Extensor carpi radialis brevis
  • Superficial branch of radial nerve
Hand
  • 3 thenar muscles
  • Lateral 2 lambricls
  • Palmaris brives
  • 3 hypothener muscles
  • All interossii
  • Adductor polices
  • Medial 2 lambricls

Differential diagnosis of nerve injuries in upper limb (anatomy is the the key)

Median nerve

Ulnar nerve

Radial nerve

Site of injury
  • Wrist
  • Elbow
  • Elbow
  • Wrist
  • Axilla
  • Spiral groove
  • Elbow
Special forms of injury
  • Carpal tunnel syndrome
  • Cut wrist
  • Fracture lower end of humerus
  • Delayed ulner neuritis
  • often follows cubitus valgus deformity due to old injury of lower end of humerus
  • Fracture shaft of the humerus
  • Intramuscular injection in triceps
  • Postoperative tourniquet
  • Saturday night palsy
  • Crutch injury
Sensory effects
  • Palmar aspect of the radial side of the hand as well as of the thumb, index, middle and half of the ring finger
  • Inner one and  half fingers in front and behind
  • Ulner side of the hand and the wrist

If lesion at wrist

  • Loss only on anterior aspect
Injury high in the arm

  • radial 2/3 of the dorsum of the hand is expected but practically
  • First interosseous space dorsally
Motor effects Pronators

  • Loss of pronation of forearm

Flexor carpi radialis

  • Defective flexion of wrist on radial side
  • Impaired radial abduction

Flexors

  • Loss of power in hand grasp
  • Terminal phalenx of thump can not be flexed

Pointing index

  • The index can not be flexed at the interphalangeal joints or at the metacarpophalangeal joint
  • Due to paralysis of its long two flexors and the lateral 2 lambricles

Outer group of short muscles of the thumb

  • Wasted and flattened of the thenar eminence
  • Thump in extended by side of the fingers
Flexor carpi ulnaris

  • Weakness of flexion and flattening of the inner border of forearm

Inner half of the flexor profundus

  • Weakness of grasp of the hand
  • Weakness of Flexion of terminal phalanx of ring and little finger

Medial 2 lumbricles

  • Partial claw-hand

Medial 2 lumbricles + flexor profundus (high ulnar nerve lesion)

Ulnar paradox

Interosseous muscles

  • Card-board test (the patient can not grip a sheet of paper between the extended fingers)

Adductor policis

  • Forment’s test
Triceps

  • Weakness of extension of elbow in abducted shoulder

Supinator

  • Hand is pronated
  • Supination can still performed by biceps

Brachioradials

  • Weakness  of flexion of elbow in med-pron position

Extensors

weakness of extension of wrist and metacarpophalyngeal joint

Grasp is weak

  • Flexor can not be tightened by extending the wrist joint
Deformity Simian or ape-like hand Partial claw-hand

Flexion of interphalangeal joints and hyperextension of metacarpophalangeal joints of the medial 2 fingers

Fingers drop

Wrist drop if extensor carpi radialis longus is involved (injury above insertion of brachialis)

Diagnosis of nerve injury by the thump
Abduction Median nerve
Adduction Ulnar nerve
Extension Radial nerve
Quick test for diagnosis of nerve injury by movement
Extend the wrist Radial nerve
Abduct the fingers Ulnar nerve
Abduct the thumb Median nerve
Diagnosis of nerve injury by testing the sensation in the hand
Lateral aspect of base of thumb Radial nerve
Little finger Ulnar nerve
Index finger Median nerve
Causes of claw hand
  • Partial claw hand
    • Ulnar nerve lesion
  • Complete claw hand
    • Volkman’s ischemic contracture
    • Combined ulnar and medial nerve injuries
    • Medial cord injury
    • Lower brachial plexus injury
    • Ulnar bursitis
    • Advanced rheumatic arthritis
Differences between Volkmann’s contracture and ulnar claw hand

Volkmann’s contracture claw hand

Ulnar claw hand

Flexion of the wrist leads to extension of the fingers Flexion of the wrist does not lead to extension of the fingers
Lost forearm pulsation Intact pulsation
Atrophy of flexor muscles No atrophy of forearm muscles