Vibration perception thresholds in entrapment and toxic neuropathies.

Due to the ever-increasing problems associated with carpal tunnel syndrome in the workplace where exposure to neurotoxic substances may also occur, measure of nerve function addressing both of these neuropathies is needed. Limitations in the standard neurological examination and nerve conduction studies have resulted in efforts to develop portable instruments for quantitative sensory testing. Fingertip vibration perception is altered in carpal tunnel syndrome and toxic neuropathies. Vibration perception is described for the median-innervated II digit and the ulnar-innervated V digit using an Optacon tactile stimulator. Discussion focuses on the interaction between toxic and entrapment neuropathies as reflected by vibration thresholds.