Brachial Plexus Lesions

Anatomy

  • Ventral rami of C5 to T1, forming roots, trunks, divisions, cords and terminal branches
  • Supraclavicular lesions (roots, trunks) more common in trauma than infraclavicular

Aetiology

  • Mostly high energy trauma, especially motorcycle accidents
  • Head and shoulder separation injures C5 and C6, forced arm abduction injures C8 and T1

Classification

  • Preganglionic lesions (root avulsion) lie proximal to the dorsal root ganglion and cannot be repaired
  • Postganglionic lesions can be repaired or grafted
  • Upper roots, anchored to transverse processes, more often rupture postganglionically
  • C8 and T1 more often avulse

Clinical Features

Preganglionic signs

  • Horner syndrome from T1 sympathetic involvement
  • Winging from long thoracic palsy, rhomboid weakness from dorsal scapular palsy
  • Raised hemidiaphragm from phrenic palsy
  • Severe burning pain in an anaesthetic limb
  • Absent supraclavicular Tinel sign, a positive sign suggesting postganglionic rupture

Associated injuries

  • Subclavian or axillary artery injury
  • Fractures of clavicle, scapula, first rib and cervical spine

Investigations

Brachial Plexus Lesions, the brachial plexus
The brachial plexus. Image by Brachial_plexus.jpg: Original uploader was Mattopaedia at en.wikipedia derivative work: Rafael Di Marco Barros, Wikimedia Commons, Public domain.
  • Chest radiograph for rib fractures and diaphragm position
  • CT myelography or MRI for root avulsion and pseudomeningocele
  • NCS and EMG at 3 to 4 weeks, with preserved SNAPs and paraspinal denervation indicating avulsion

Management

  • Sharp open injuries explored and repaired early
  • Closed injuries observed, explored at 3 to 6 months without recovery
  • Surgery within about 6 months gives the best results
  • Priorities are elbow flexion, then shoulder stability, then hand sensation and function
  • Neurolysis and sural nerve grafting
  • Oberlin ulnar fascicle to biceps and double fascicular transfers
  • Spinal accessory to suprascapular, triceps branch to axillary, intercostal and contralateral C7 transfers
  • Free gracilis transfer for late or pan-plexus injuries
  • Steindler flexorplasty, latissimus transfer and shoulder arthrodesis as secondary procedures

Prognosis

  • Upper plexus injuries have the best outcome
  • Pan-plexus avulsions leave a poorly functioning hand

Obstetric palsy

  • Linked to shoulder dystocia, macrosomia and instrumented delivery
  • Erb palsy (C5, C6) most common, with waiter’s tip posture
  • Absent biceps recovery by 3 to 6 months indicates microsurgical reconstruction
  • Internal rotation contracture and glenohumeral dysplasia are common sequelae

Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.