tos
Table of Contents
thoracic outlet syndrome
see also:
- pectoralis minor compression of axillary vein
Introduction
- 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
Aetiology
- cervical rib
- pectoralis minor syndromes
- anterior scalene syndrome
- costoclavicular syndrome
- diagnosed with the costoclavicular maneuver
- trauma
Clinical features
neurogenic TOS
- 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:
arterial TOS
- 1% of cases
venous TOS
- 4% of cases
- painful, swollen and blue arm, particularly when occurring after strenuous physical activity
tos.txt · Last modified: 2026/01/06 10:18 by gary1