Thoracic Outlet Syndrome (TOS) is an umbrella term that refers to the compression of nerves and blood vessels as they travel from the neck to supply the arm. More specifically, the Brachial Plexus (a group of nerves carrying sensory and motor information), and the subclavian artery and vein become entrapped. The compression of these neurovascular structures occurs with the narrowing of small spaces in the Thoracic Outlet. The Thoracic Outlet extends from the borders of the collar bone (clavicle), first rib, and neck muscles (anterior and middle scalene). There are 3 common sites within the Thoracic Outlet that can become entrapped: between the scalene muscles, under the collar bone, and beneath the tendon of the pectoralis minor muscle.

Risk Factors

Motor vehicle accidents (ie. whiplash), Tramatic Injuries

Repetitive strain, Carrying a heavy backpack

Congenital / extra cervical ribs

Signs and Symptoms 

Neck, shoulder, and arm pain

Weakness in the arm and hands

Reduced sensation in the hands

Tingling sensation into the arm