The term "thoracic outlet syndrome" describes a set of manifestations corresponding to the entrapment of the neurovascular bundle that comprises the brachial plexus, axillary vein and artery in a region named thoracic outlet. We still don't have a gold standard diagnostic tool, although different clinical, radiographic and electrodiagnostic tests have been described. The authors describe the case of a 16-year-old female adolescent who came to the ambulatory of the Rheumatology Department complaining of right shoulder pain and ipsilateral forearm and hand disesthesias for 3 months, which were aggravated with arm abduction movements. The right arm hyperabduction maneuver was associated with the symptoms and significant weakening of ipsilateral radial pulse and arterial pressure, but not in the contralateral arm, so a right thoracic outlet syndrome (TOS) was diagnosed. Thoracic axial computerized tomography didn't show any infraclavicular or axillary tumors. The axillary Doppler showed a triphasic wave in the subclavian artery, which lead to the performance of a right subclavian and axillary arteries angiography. It was normal in neutral position but, with arm hyperabduction, a reduction in the amount of contrast in the axillary artery was evident, meaning a local entrapment. The authors propose that, when the clinical evaluation suggests TOS and an arterial compression is suspected, an angiography should be ordered in order to localize and characterize it. The cause of this compression was considered to be a shoulder muscle hipotonia, which was successfully compensated by a set of stretching and reinforcement exercises.
thoracic outlet syndrome; angiography; diagnosis
