Diagnosis | Thoracic outlet syndrome

Diagnosis

A first indication of the diagnosis is given by the described symptoms of the patient.Based on these symptoms, a first suspected diagnosis can usually be made. In addition, an x-ray of the rib cage and possibly also of the cervical spine is made. On this x-ray, an osseous structure responsible for the symptoms, such as a cervical rib, can be found or excluded.

Since the nerves of the arm can also be affected in thoracic outlet syndrome, the measurement of nerve conduction velocity can confirm or exclude damage. The nerve conduction velocity is mainly measured in the region of the ulnar nerve (ulnar nerve) and the median nerve (central nerve). In addition, there are some manual tests that can provide important information for the diagnosis of Thoracic outlet syndrome.

In addition, other imaging techniques can be used to identify constrictions and possible causes. Within the framework of diagnosing thoracic outlet syndrome, there are some test examinations that can cause the symptoms or a worsening of the symptoms. Among others, the so-called Adson test is used here.

The patient turns his head in the direction of the affected arm up to his movement or pain limit. At the same time, the radial pulse is felt on the wrist. In the case of a pathological narrowing, this pulse becomes significantly weaker during the test.

Another test is the so-called Roos test, in which the patient raises his arms at an angle, i.e. he puts his hands up and tries to close both fists. This test can provoke or even increase pain. MRI also plays an important role in the diagnosis of thoracic outlet syndrome.

Here too, as in the context of X-ray diagnostics, possible bone changes can be shown. In addition, MRI can reveal soft tissue changes that may cause constrictions. Vessels and vascular changes such as dilatation or constriction can also be shown.

This procedure is then referred to as MR angiography. A contrast medium containing gadolinum is used here. Normal” angiography can also be used to visualize vascular changes in the context of thoracic outlet syndrome.

In this case, a catheter is inserted through a vascular access in the groin in the direction of the subclavian artery in order to visualize the desired area. In contrast to MR angiography, iodine-containing contrast medium is used in “normal” angiography. Another difference is the extent of radiation exposure.

The standard angiography is performed using X-rays. Angiography using MRI, on the other hand, uses a magnetic field to produce the images. During the examination by angiography, the affected arm is moved into a “provocative position” in order to induce possible narrowing of the vessels.