Mechanism of Vascular Tests in Thoracic Outlet Syndrome

Vascular tests for thoracic outlet syndrome are considered to be one of the important diagnostic aid in order to determine the localization and the severity of neurovascular lesion at the thoracic outlet region. However, the mechanism and significance of vascular tests are still unclear.This is to report our clinical and autopsial study to try to clarify the exact meanings of each vascular test.Materials are 72 cases in 48 patients with thoracic outlet syndrome (46 cases in 39 patients recieved first rib resection) and 21 cases of exploration in autopsy.Positive Adson's test, although the incidence is quite low, may suggest severe lesion at the scalen triangle. Eden's test indicate lesions at the costo-clavicular space. In this positive the clavicle moves most to the posteromedial direction among the various positions. Abduction-external rotation test and Wright's test show neurovascular compression mainly at the costo-clavicular region and partly at the scalen triangle. These positions make the neurovascular bundle tracted foward the lateral. Compression at the subcoracoideal region is not the main cause in Wright's test.