Thoracic Outlet Syndrome G54.0 353.0

ICD-9 Classification / Treatment
Etiology / Epidemiology / Natural History Associated Injuries / Differential Diagnosis
Anatomy Complications
Clinical Evaluation Follow-up Care
Xray / Diagnositc Tests Review References



G54.0:    Brachial plexus disorders


  • 353.0 (Brachial plexus lesions; cerical rib syndrome, costoclavicular syndrome, scalenus anticus sydrome, thoracic outlet syndrome)

TOS Etiology / Epidemiology / Natural History

  • Etiology: compression of the neurovascular structures (subclavian vessels, brachial plexus, cervical ganglia, and vertebral artery) in the cervicoaxillary region. May be congenital or acquired.
  • Bony causes: long transverse process of the 7th cercial vertebra, cervical rib, anomalous 1st rib, clavicle fracture, 1st rib fracture.
  • Soft tissue causes: congenital bands, poor posture, mass lesions, cervical strain, hypertrophy and/or injury of the anterior and middle scalene muscles or the pectoralis minor muscle.
  • must rule out all other possible diagnoses
  • aggravating factors=trapezius weakness, obesity, excessively large breasts.
  • women:men=3.5:1

TOS Anatomy

TOS Clinical Evaluation

  • Numbness, tingling, early fatigue, weakness, pain in neck or shoulder. Numbness and tingling may involve entire upper limb or forearm and hand. 
  • ulnar side of limb and two ulnar digits are predominantly involved
  • nocturnal pain and paresthesias common
  • difficulty with overhead activity.  Occasional c/o numbness carrying things, typing or driving.
  • +/- pain in arm, shoulder, neck, chest, limb swelling,
  • Trapezious atrophy, eval neck ROM,
  • Complete Neurovascular exam indicated.
  • Adson’s: arm at side, neck hyperextended, head turned toward affected side reproduces symptoms
  • modified Adson’s
  • Wright’s:arm abducted and ER, pt takes deep breath and holds it. 
  • provocative position and compression test(manual compression to the brachial plexus in various positions)=most reliable (Novak CB, J Hand Surg 18A;292:1993)

TOS Xray / Diagnositc Tests

  • NCV, EMG, xray, CT, sensory test all will be normal
  • angiography/ultrasound are frequently abnormal in a normal poplulation
  • NCV/EMG indicated to r/u more distal lesion
  • Anterior scalene and/or pectoralis minor muscle blocks using local anesthetics have been used in diagnosis(Jordan SE, Ann Vasc Surg 1998;12(3):260).

TOS Classification / Treatment

  • Initial=correction of posture, supraclavicular muscular stretching and strengthening exercises of the lower scapular stabilizers and activity modification (Novak CB, J Hand Surg 20A;542:1995); often takes 2+months to show improvement.
  • Avoid enciting activities, lose weight, better supporting bra/reduction mammoplasty.
  • Operative = thoracic outlet decompression via transaxillary or supraclavicular approach, typically removal of the first rib, resection of the anterior/middle scalene muscles, +/- brachial plexus neurolysis; in cases associated with localized tenderness over the subpectoral space, consider pectoralis minor tenotomy. (Thompson RW, Ann Vasc Surg 1997;11:315).
  • Supraclavicular decompression allows more complete anterior/ middle scalenectomy and ability to perform brachial plexus neurolysis with direct visual protection of the brachial plexus nerve roots.

TOS Associated Injuries / Differential Diagnosis

  • Cervical radiculopathy
  • Supraclavicular fossa pathology
  • Thoracic outlet syndrome
  • Subclavian Artery Stenosis / Aneurysm
  • Lung tumor; Pancoast tumor
  • Brachial neuritis
  • CTS
  • Ulnar tunnel syndrome
  • Cubital tunnel syndrome
  • CRPS
  • Paget-Schroetter
  • Axillary Artery Aneurysm

TOS Complications

  • Recurrence
  • Infection
  • Brachial plexus injury
  • Vascular injury
  • Pain
  • CRPS

TOS Follow-up Care

  • Up to 40% recurrence after transaxillary first rib resection (Altobelli GG, J Vasc Surg 2005;42:122).
  • Up to 10% recurrence after supraclavicular decompression

TOS Review References

  • Leffert, RD, JAAOS 1994;2:317
  • Sanders RJ. Thoracic outlet syndrome: a common sequelae of neck injuries. Philadelphia: J.B. Lippincott Company; 1991.