Upper Limb Birth Palsies

Incidence

  • Most common birth palsies
  • 1/1000 live births » 1 in 10 of these = permanent impairment
  • Increased risks
    • high birth weight
    • Prolonged labour
    • Breech
    • Shoulder dystocia

Aetiology

  • Lateral flexion of head on trunk
  • Forceps may contuse plexus directly
  • May occur after CS

Pathology

  • Most – at level of neural foramen or groove of transverse process
  • Effect varies with force (lower plexus takes less force to disrupt)
  • Stages
    • Mild
      • perineural oedema, haemorrhage
      • rapid & complete recovery
    • Moderate
      • some nerve fibres disrupted, intra & extraneural bleeding
      • recovery slow + incomplete
    • Severe
      • avulsion of trunks or roots
      • worst prognosis but some recover
      • Incomplete recovery »
        • muscle contractures & secondary skeletal changes
        • Most commonly medial rotation & adduction of shoulder
          • (contractures of subscapularis, pec major, teres major, short head biceps)
      • Severe cases
        • posterior subluxation or dislocation shoulder
        • Flattening of humeral head
        • Retroversion of humeral neck
        • Glenoid fossa shallow
        • Scapula high

Classification

  • Upper root injury (C5, C6) Erb-Duchenne
    • Commonest
    • Involved muscles
      • deltoid, lateral rotators, biceps, brachialis, brachioradialis, supinator
    • Waiter’s tip
      • Shoulder: adducted & internally rotated
      • Forearm: pronation contracture
      • Wrist: fixed flexion
    • Minimal sensory loss
    • May develop later elbow flexion contracture
  • Complete injury
    • Second most commen
    • Flaccid paralysis entire upper limb
    • ± vasomotor changes » marbled appearance of hand
  • Lower root injury (C8, T1) Klumpke
    • Least common
    • Involved muscles
      • wrist flexors, long finger flexors, intrinsics
    • Hand function poor, fingers flexed, shoulder & elbow function is good

Diagnosis

  • Absence of active movement in the newborn
  • Moro reflex absent in affected limb (Grasp reflex lost in complete or lower injuries)
  • T1 may be affected » Horner’s (bad prognostic sign)
  • Phrenic nerve may be affected » raised hemidiaphragm

Differential

  • Pseudoparalysis
    • Delivery fractures
      • clavicle common (5% associated with obstetric palsy)
      • Midshaft humerus
    • Dislocation
      • shoulder or elbow is rare
    • Osteomyelitis / septic shoulder
      • Includes E-coli & group B strep
  • Arthrogryposis

Management

  • Most recover in 1st 3 months
    • Use passive ROM 3 – 4 times per day to avoid contractures
  • Surgical exploration of plexus
    • only after 3 months trial observation
    • ± consider electromyography
    • Supraclavicular approach
    • Nerve reconstruction – graft or repair (sural n)
    • Neurotization – (re-routing other nerves)
    • Upper plexus = better results than lower

Late deformity

  • Aim to compensate for the fixed adduction & internal rotation

Soft Tissue

  • Open reduction shoulder
    • Hold temporarily with K-wire
    • Shoulder spica
  • SEVER release
    • Release or lengthen pec major & subscapularis
      • Improves range of ER & abduction
  • L’Episcopo procedure
    • Transfer teres major to more lateral position
    • With lateral dorsi » improves ER & abduction power
  • lengthen brachialis & biceps
    • if elbow fixed flexion is compensating for residual shoulder deformity
  • pronator teres lengthening
    • Fixed pronation forearm
      • osteoclasis of radius may also be needed

Bone

  • External rotation humerus
    • After 6 years old
    • But by then = ~40 % chance of posterior dislocation (therefore reduce earlier)