Thoracic Outlet Syndrome: Biomechanical and Exercise Considerations

Abstract

Thoracic outlet syndrome (TOS) describes a group of disorders that are due to a dynamic compression of blood vessels or nerves, between the clavicle and first rib or cervical vertebral nerve roots. Individuals with TOS typically experience upper limb pain, numbness, tingling, or weakness that is exacerbated by shoulder or neck movement. The causes of TOS vary, and can include abrupt movements, hypertrophy of the neck musculature, and anatomical variations in which the brachial plexus roots pass through this musculature, edema, pregnancy, repeated overhead motions, the blockage of an artery or vein, or abnormal posture. To understand the complexity of this condition, an analysis of shoulder anatomy and mechanics are needed to help describe limitations and the subsequent pathophysiology of TOS. Several treatment options are available, including surgery, medications, and exercise. A comprehensive study of shoulder anatomy and biomechanics, and knowledge of the benefits of exercise, may help clinicians and healthcare practitioners determine the most appropriate treatment plan for an individual with TOS.

Arm numbness at 45 degrees abduction: A case report of thoracic outlet syndrome post brachial neuritis

“…Our hypothesis is that with the patient's history of brachial neuritis, there was already atrophy in the shoulder girdle leading to biomechanical dysfunction, predisposing her to TOS. The association of brachial neuritis contributing to TOS, to our knowledge, has not been described before; however, muscle weakness leading to abnormal shoulder or head position has been described as contributing to TOS (7,8). It is unclear if the patient also had an underlying anatomical variation with asymmetry in her costoclavicular space or a congenital fibrous band that was not previously known.…”

Evaluation of the efficacy of ropivacaine injection in the anterior and middle scalene muscles guided by ultrasonography in the treatment of Thoracic Outlet Syndrome

“…Thoracic Outlet Syndrome (TOS) is a group of disorders characterized by the compression of the brachial plexus and subclavian vessels at any point of the thoracic outlet region [1][2][3] . It includes painful, sensorial, and motor manifestations on the neck, shoulder, upper limb, and shoulder girdle region.…”

Endoscopic Release of the Brachial Plexus

“…Thoracic outlet syndrome (TOS) is a debilitating condition, impairing the function of the upper limb, and can be considered an entrapment of neurovascular structures dedicated to the upper limb. 1 , 2 The entrapment can be situated at different levels between the neck and the arm, including the interscalene triangle, the upper border of the first rib (by the rib itself or a hypertrophic transverse cervical process with or without fibrous bands), the costoclavicular space, the retro-coracoid, the pectoralis minor, and the penetration point of the neurovascular bundle at the level of the brachialis fascia. 1 The exact location of the entrapment, as well as the cause of the compression and the structures involved, such as the brachial plexus and subclavicular vein and artery, can be difficult to access.…”

“… 3 In this scenario, bony compression resulting from narrowing of the space between the clavicle and the first rib or a cervical rib, which was previously considered the main cause of entrapment, will be responsible for just 20% to 30% of the cases. 1 , 2 …”