investigations
Last reviewed 07/2023
Investigations for thoracic outlet syndrome may include:
- blood pressure:
- lower on the affected side
- variable with arm abduction
- X-ray:
- a bony cervical rib may be seen directly
- a fibrous band is indicated by an enlarged anterior tubercle of the seventh cervical vertebra
- apical lung tumour in Pancoast's syndrome
- nerve conduction / electromyography:
- distinguishes thoracic outlet syndrome from other peripheral nerve lesions
- arteriography:
- long standing compression of the subclavian artery may result in a post-stenotic dilatation
- abduction and external rotation of the shoulder may cause complete obstruction of subclavian blood flow in cases associated with a cervical rib