Thoracic Outlet Syndrome: Signs, symptoms and physiotherapy treatment
Thoracic outlet syndrome (TOS) is a complex clinical presentation caused by the irritation, compression or traction of the nerves, arteries or veins that pass through the thoracic outlet, a small anatomical space between the clavicle (collarbone), first rib and cervical spine vertebra (Fig 1).
Figure 1: The anatomy of thoracic outlet syndrome (Retrieved 29/10/16 from: http://www.brighamandwomens.org/Departments_and_Services/lung-center/lung-diseases-and-conditions/thoracic-outlet-syndrome.aspx)
The subclavian artery and vein supply and drain blood respectively to the arm and hand. Compression of one or both of these blood vessels is known as Vascular Thoracic Outlet Syndrome. Vascular TOS normally results from a structure lesion. Anatomical abnormalities such as a cervical rib or previous fractures and bone injuries can alter the shape of the thoracic outlet, resulting in compression of these blood vessels.
Severe cases of vascular TOS will result in compromised blood flow to the arm and is considered a medical emergency, usually requiring surgery. There are many signs and symptoms of vascular TOS including, but not limited to, swelling, cyanosis or a bluish discoloration, vein enlargement, fatigability, paraesthesia, coldness and cramps in the arm and hand. Milder cases can display similar signs and symptoms and should always be examined by a medical professional so proper vascular investigations can be performed.
The nerves of the arm and hand originate from the brachial plexus (Fig 1). Compression, irritation or traction to any part of the brachial plexus as it passes through the thoracic outlet is known as Neurological Thoracic Outlet Syndrome. This will result in neurological symptoms in the neck, arm and hand including but not limited to, numbness, tingling, pins and needles, pain and loss of motor control and strength (Watson & Pizzari, 2010).
TOS is typically aggravated by increased activity in the affected arm and repetitive or sustained overhead arm movement. Poor upper body and scapula postures result in depression of the clavicle creating a downward traction on the neurovascular complex passing through the thoracic outlet. Occupational and sporting stressors that require repetitive use of the arms can result in intermittent irritation of these structures (Watson et al, 2010). These factors can be modified and patients may benefit from a course of physiotherapy treatment including:
· A graded rehabilitation program that improves scapula muscle control and posture (Watson et al, 2010)
· Manual therapy and stretching to tight soft tissue structures
· Postural taping
· Ergonomic advice
Identifying TOS is not straightforward because there isn’t one specific clinical test or investigation to diagnose the condition. Diagnosis requires a detailed subjective and physical examination exploring the contributing factors mentioned above. Imaging, neurological and vascular investigations may be indicated, and in some cases a referral to an appropriate medical specialist should occur. Neurological TOS can be responsive to physiotherapy treatment so if you think you are showing some of the signs and symptoms speak to a physiotherapist.
Daniel Di Mauro is a McKenzie credentialed physiotherapist in St Albans, Melbourne. Daniel has a special interest in pain management for complex low back pain, as well as soccer related injuries. Daniel was a treating physiotherapist in the recently published trial on physiotherapy for multidirectional instability of the shoulder by Sarah Warby & Lyn Watson.Daniel provides expert physiotherapy services to Caroline Springs, Keilor, Sunshine, and Taylors Lakes.
Watson, LA & Pizzari, T. (2010). Thoracic outlet syndrome part 1: Clinical manifestations, differentiation and treatment pathways. International Journal of Osteopathic Medicine, 13: 133-142
Watson, LA. Pizzari T & Balster, S. (2010). Thoracic Outlet Syndrome Part 2: Conservative management of thoracic outlet syndrome. Manual Therapy, 15: 305-314