Non-invasive investigation of vascular compression in patients with thoracic outlet syndrome.

Three hundred and seventy-seven patients with brachial pain and 63 controls have been examined regarding presence of symptomatic compression of the brachial plexus and subclavian vessels (Thoracic Outlet Syndrome = TOS). Each patient was examined clinically and by Doppler flowmetry. Two hundred and thirty (61%) had moderate to pronounced compression of the brachial plexus and 11 (2.9%) isolated compression of the subclavian artery or vein. One hundred and twenty-nine patients had symptoms not related to TOS. The prevalence of TOS was almost twice as common in women as in men, 1.76:1. The TOS patients were younger than the non-TOS patients, P less than 0.05. There was a significant correlation between arterial compression measured by Doppler flowmetry and the presence of compression of the plexus, P less than 0.001. But the validity of this method was not satisfactory, giving both false positive and negative results. Furthermore, there was a very good correlation between arterial compression assessed clinically and by Doppler flowmetry, P less than 0.001. Thus, the diagnosis of TOS is still a clinical judgement, the Doppler technique adding very little and any significant vascular compression being easily detected by clinical assessment.