thoracic outlet syndrome

see also:

• subclavian steal syndrome
• pectoralis minor compression of axillary vein
  • https://www.sciencedirect.com/science/article/pii/S0741521407001498

• thoracic outlet syndrome is an uncommon pathology where either nerves, artery, or veins to the arm or head are compressed after they leave the thoracic outlet

• cervical rib
• pectoralis minor syndromes
• anterior scalene syndrome
• costoclavicular syndrome
  • diagnosed with the costoclavicular maneuver
• trauma

• 95% of cases of TOS
• compression of brachial plexus nerves (C5-T1)
• frequently occurs in those in their second to fourth decades of life
• 70% of those affected being female
• clinical features may include:
  • pain or aching in neck, shoulder, arm, or hand;
  • paresthesias in ulnar distribution
  • hand weakness, fatigue, or atrophy (e.g., thenar or intrinsic muscles)
  • headache is common due to secondary spasm of paraspinal and trapezius muscles
  • symptoms worsen with overhead activity (eg hanging clothes, brushing hair), poor posture or perhaps repetitive motions like walking
  • tenderness at the point of plexus compression:
    • the scalene triangle in the supraclavicular space, or,
    • at the pectoralis minor insertion site at the coracoid process
• see also:
  • https://www1.racgp.org.au/ajgp/2023/september/neurogenic-thoracic-outlet-syndrome

• 1% of cases

• 4% of cases
• painful, swollen and blue arm, particularly when occurring after strenuous physical activity