Nerve conduction tests in patients with fibromyalgia: comparison with normal controls.

The purpose of this study was to evaluate nerve conduction in fibromyalgia (FM) patients and normal subjects. Testing of F waves and motor, sensory, and mixed nerve conduction was performed in 33 consecutive female FM patients complaining of paresthesias in the extremities and in 17 age- and sex-matched healthy volunteers. The nerve conduction results in FM patients were no different from those of normal subjects except for prolonged peroneal distal motor latency ( P=0.048) and decreased peroneal motor conduction velocity ( P=0.030). Five of the 33 patients (15%) showed abnormalities in peroneal nerve conduction, five (15%) had carpal tunnel syndrome (CTS), and overall nine (27%) had electrophysiologic findings of focal entrapment, which indicated that focal neuropathies were common in this patient group. There was no evidence of generalized polyneuropathy in the FM patients.