Correspondence between neurological symptoms and outcome of quantitative sensory testing in the hand-arm vibration syndrome.

To evaluate neurological symptoms in the vibration syndrome, 55 patients with vascular and neurological symptoms in the hand who had been exposed to vibration were examined. Their exposure to vibration was estimated and neurological vascular symptoms were evaluated according to symptom scales. Temperature thresholds were measured on the right thenar eminence and on the distal volar aspect of the second and third fingers held together on both sides. Vibration thresholds were measured dorsally on the second and fifth metacarpal bones and on the second and fifth fingers proximal to the nail roots. Subjects with advanced neurological symptoms had higher temperature and vibration thresholds than subjects with less advanced symptoms. No such relation was found between vascular symptoms and the outcome of sensory testing. Thus neurological but not vascular symptoms are reflected by the outcome of quantitative sensory testing. In subjects with advanced neurological symptoms the tests gave a high proportion of abnormal results, indicating that these tests may be used for the diagnosis of vibration syndrome on an individual basis. Patients with advanced vascular and neurological symptoms had higher exposure dose scores than patients with less advanced symptoms, indicating a dose response relation between vibration "dose" and neurological and vascular symptoms.