The differential diagnosis of thoracic outlet syndrome

Thoracic outlet syndrome (TOS) is a heterogeneous group of disorders which occures with the compression of one or more neurovascular elements at the cervicobrachial region. It is also a cause of neck and shoulder pain due to complex mechanisms. Diagnosing TOS can be difficult due to a great variety of symptoms may be seen in this disorder. These symptoms can simulate different diseases such as neck, shoulder and elbow pathologies and peripheric neuropathies or TOS may associate with other peripheric neurpathies. Thus once a peripheric neuropathy diagnosed, the possibility of an additional TOS should be investigated. Despite all these challenges, a clinical practice guideline for differential diagnosis of TOS is not determined yet. A careful history and thorough clinical examination are the most important components of the diagnosis. This article aims to discuss the clinical features and physical examination methods of the other related upper extremity and cervical pathologies in order to make an accurate differential diagnosis for TOS.