Thoracic Outlet Syndrome

Question 1

Definition of thoracic outlet syndrome (TOS)

Answer 1

Constellation of symptoms related to compression of the neurovascular elements foudn in the thoracic outlet (brachial plexus, SC artery, SC vein)

Question 2

Three types of TOS

Answer 2

• Neurogenic TOS (MC, 90-95%)
• Arterial TOS
• Venous TOS (may progress ot Paget-Schroetter syndrome)

Question 3

Paget-Schroetter syndrome

Answer 3

Axillosubclavian vein thrombosis

• Effort induced thormbosis
• Occurs in patients performing repetitve mtion of the arm (pitchers, swimmers, etc)

Question 4

Etiology of TOS

Answer 4

• Anterior scalene muscle hypertrophy
  
  • Brachial plexus or SC artery compression
• Costoclavicular syndrome
  
  • Narrowing of the space between clavicle and 1st rib
• Cervical rib
• Trauma

Question 5

Demographics of Thoracic Outlet Syndrome

Answer 5

• Females (4:1)
• 20-40 years of age

Question 6

Most common presentation of Thoracic Outlet Syndrome

Answer 6

• Pain
• Numbness
• Tingling of arm/hand
• Arm swelling (occlusive thombus in venous TOS)
• Distal arm/hand ischemia (arterial TOS)

Question 7

4 clinical exam maneuvers use to elicit signs/symptoms of thoracic outlet syndrome

Answer 7

• Costoclavicular test:
  
  • patient holds shoulders down and backward (narrows costoclavicular space)
• Adson test:
  
  • patient takes deep breath while extending neck and turning head toward affected side (narros interscalene triangle)
• Roos test:
  
  • patient holds arms at 90 degrees of abduction and external rotation with shoulders drawn back, patient hands opened and closed for 3 minutes
• Wright test:
  
  • patient hyperabducts and externally rotates arms

Question 8

Diagnostic evaluation for TOS

Answer 8

• H&P
• X-ray (C-spine and chest)
  
  • Exclude cervical vertebral anomalies and cervical rib
• CT (IV contrast) or MRI
  
  • Neutral position with arms above head
• Arteriogram and/or venogram
  
  • Sx of arterial (digit ischemia) or venous TOS (arm swelling)
  • Not routinely performed as most patients have neurogenic TOS

Question 9

Treatment of choice for TOS

Answer 9

• Physical therapy (initial TOC)
  
  • Strengthen shoulder structures
  • Correct posture
• Surgical therapy
  
  • Non-responsive to conservative management and PT

Question 10

Surgical approach to TOS

Answer 10

• First rib resection with scalenectomy
  
  • Supraclavicular or trans-axillary approach
• Venous TOS
  
  • Usual TOC: thrombolysis followed by decompression (1st rib resection and scalenectomy)
  • May require supra- and infra-clavicular incisions
  • May require venous angioplasty or reconstruction after decompression
• Arterial TOS
  
  • May require arterial reconstruction in addition to 1st rib resection and scalenectomy