Thoracic outlet syndrome

From greek.doctor
  • Symptoms occurring due to compression of structures like
    • Brachial plexus (95% of cases)
    • Subclavian vein (4% of cases)
    • Subclavian artery (1% of cases)
  • Caused by narrowing of the anatomical opening called “thoracic inlet”, “thoracic outlet” or “superior thoracic aperture”, which is a hole surrounded by
    • Clavicula
    • The first rib
    • Scalenus anterior
    • Scalenus medius
  • If the thoracic outlet becomes narrower some or all of the neurovascular structures may be compressed
  • Etiology
    • Trauma
      • Collarbone fracture
    • Hypertrophy of scalenus muscles
    • Pancoast tumor
    • Congenital cervical (extra) rib
  • Clinical features
    • Neurogenic thoracic outlet syndrome
      • Due to compression of brachial plexus
      • Pain, anaesthesia, paraesthesia in neck and arm
      • Often in areas innervated by ulnar nerve
    • Venous thoracic outlet syndrome
      • Due to compression of subclavian vein
      • Swelling
      • Venous distension
      • Venous thrombosis
    • Arterial thoracic outlet syndrome
      • Due to compression of subclavian artery
      • 4 Ps
        • Pulselessness (in the hand)
        • Pain
        • Pallor
        • Paraesthesia
  • Treatment
    • Physical therapy
      • In mild cases, can be enough
    • Thoracic outlet decompression surgery
      • Transaxillary resection of extra rib or first rib
      • Angioplasty, if vessels are affected
  • Cervical rib
    • Some people have a congenital extra rib before the first rib called the cervical rib
      • The first rib starts at Th1
      • The cervical rib starts at C7
    • This cervical rib compresses the thoracic outlet, causing TOS
    • The treatment is surgical resection of the cervical rib