Adson Test: For Adson Maneuver the examiner externally rotates and extends the effected arm with the elbow extended while monitoring the radial pulse. The patient is then instructed to rotate the head toward the affected side, extend the neck and take a deep breath and hold it. The absence of disappearance of a pulse indicates a positive test (Magee DJ, 2008). In 1947, Adson first described this test with the explanation that an alteration of the radial pulse or an alteration in blood pressure is considered a pathognomonic sign of scalenus anticus syndrome indicating that the vascular component of neurovascular bundle is compressed by scalenus anticus muscle. (Mackinnon SE, 2002)