Sean Thomson

December 01, 2017

Brisbane Physiotherapist Sean Thomson commonly treats shoulder pain and explains there can be many causes and just as many effective treatments. When nerves are compressed however, the signs and symptoms are unique to a condition referred to as Thoracic Outlet Syndrome (TOS). The thoracic outlet, is the space between the clavicle, first rib and manubrium (upper sternum).  This space is dynamic and therefore changes in size with the movement of the shoulder. Thoracic outlet syndrome represents a diverse group of disorders that have one feature in common, the compression of any one or more of the neurovascular structures traversing through the thoracic outlet space (brachial plexus, subclavian vein/artery).

There are three types of thoracic outlet syndrome which are caused by three different physiological scenarios each resulting in similar pain and restriction for the patient but need very different treatments to overcome.

Neurological Thoracic Outlet Syndrome (most common)

Symptoms generally include muscle wasting in the fleshy base of their thumb, numbness or tingling in their arm or fingers and pain or aches in their neckshoulder or hand and can be accompanied by a weakening grip.  

Caused by the compression of the brachial plexus (a network of nerves that extend from the spine through the neck and into the arm), it tends to occur in people who perform repetitive overhead arm movements in their job or participate in certain sports, such as swimming or baseball. Neurogenic Thoracic Syndrome can also occur an accident as well. Some people are born with an extra rib or misshapen rib and can also develop symptoms as this puts extra pressure on the nerves in the area. 

Neurological TOS and Non-specific TOS are most appropriately treated conservatively over an 8-12 week period. Conservative management should consist of a multimodal approach including:

  • physical therapy (gentle stretching/strengthening, mobilisations, cervical traction, active exercise, postural correction, ice and taping);
  • pharmacological treatment (NSAIDs, muscle relaxants, neuropathic meds, anticoagulation, corticosteroid injections, botulinum toxin);
  • appliances (orthoses/neck collar);
  • dietician input (to aid obese patients); and
  • workplace ergonomic modifications.

Treatment at this stage should avoid aggressive strengthening/stretching and shoulder hyperextension.

Venous Thoracic Outlet Syndrome

Symptoms generally include swelling or bluish skin in the arms and swollen veins where the shoulder meets the chest. This version of TOS is caused by the compression of a vein called the subclavian, which carries blood from the upper extremities - including the shoulders, arms, and hands - to the heart. This can be life-threatening as the compression can lead to blood clots, which can travel to the heart and lungs.

People with this condition are frequently born with a narrowing of the space where the subclavian vein extends from the shoulder to the heart. Overuse of the arm and shoulder, such as during sports or work, causes the veins in the thoracic outlet to become compressed, which can lead to blood clots.

Arterial Thoracic Outlet Syndrome

Symptoms include numbness, pain, coldness and tingling in the arm and hand. The fingers and hand may appear white. Cramping of the forearm and hand during activity while typing or exercising is not uncommon also. Arterial TOS is caused by the subclavian artery which can potentially cause a blood clot. If a blood clot breaks apart and a piece of it flows into the arm it can block circulation in the elbow or hand.

Surgical intervention should be considered for Venous and Arterial TOS and also Neurological TOS - with the presence of intrinsic muscle atrophy (with no distal nerve compression) or failure to respond to conservative treatment.