[Digital vibration syndrome: neuro-physiologic study in 17 patients]

Studies were carried out on 17 male workers with clinical vibration disease who had been working with different vibrating tools (compressed-air hammers, chain-saws, rock drills, grinders) for 2 to 39 years. Their neurophysiological results were compared with those of 20 healthy men (control group). Median motor nerve conduction velocity (NCV) between elbow and wrist was significantly reduced and motor distal latency (DL) significantly longer in 43% cases. A distinct decrease of the conduction velocity of distal (finger-wrist) median sensory fibers (in 56% of cases) as well as reduced amplitude of the sensory evoked potential (62% of cases) were found. EMG showed alterations only in patients with NCV abnormalities. These electrophysiological findings point to distal axonal as well as to demyelination damage. The results, which are discussed in relation to previously published work in this field and according to a pathogenetic hypothesis of this syndrome, allowed us to draw practical conclusions for the neurophysiological examination of patients with vibration disease.