TOS

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TOS

Abbreviation for thoracic outlet syndrome.

TOS

Abbreviation for thoracic outlet syndrome.

thoracic outlet compression syndrome

, thoracic outlet syndrome,

TOS

A symptom complex caused by the compression of nerves and/or vessels in the neck, such as by the first rib pressing against the clavicle or entrapment of brachial nerves and vessels between the pectoralis minor muscle and the ribs. It is marked by brachial neuritis with or without vascular or vasomotor disturbance in the upper extremities. The practitioner must differentiate TOS from cervical disk lesions, osteoarthritis affecting cervical vertebrae, bursitis, brachial plexus injury, angina, lung cancer, and carpal tunnel syndrome.