The thoracic outlet is the space between the collarbone and the first rib. Nerves and blood vessels of the upper extremity pass through this space.
Thoracic outlet syndrome is characterized by symptoms that are attributed to the compression (squeezing) of nerves or vascular structures that pass through the space. Nerve compression can cause pain in the neck and shoulder, numbness and tingling in the fingers, and/or a weak grip. Compression of blood vessels can cause decreased blood flow to the arm, swelling, fatigue, and a sensation of coolness.
This condition can be caused by trauma, repetitive injuries, anatomical defects, and pregnancy.
History and physical exam by a qualified musculoskeletal expert and diagnostic testing is the first step. An elevated arm stress test is a common way to identify thoracic outlet syndrome. Diagnostic imaging tests including x-rays, computed tomography (CT) scans, magnetic resonance imaging (MRI) scans, and ultrasound can help see and evaluate the bones, muscles, tendons, and blood vessels. A doctor may also order special blood circulation tests and nerve conduction tests to help make the diagnosis.
A doctor may recommend physical therapy to help strengthen muscles surrounding the shoulder. Other options include non-steroidal anti-inflammatory medications which can help to reduce pain or swelling. Surgery could be an option if nonsurgical treatments do not relieve symptoms.