Nerve conduction velocity of small components in human sensory nerves. Studies in normal and diseased nerves

Slow conducted components of sensory nerve action potentials were investigated in median and in sural nerves of controls and in patients with peripheral nerve diseases. In the normal group the slow components showed no relation to age which is in contrast to the maximum velocity. In both the median nerve and sural nerve of about 20% of the patients with neuropathy exclusively a decrease of the conduction velocity of slow components was found, the other investigated parameters were normal. Possible causes are an alternation of the myelin sheath or changes in the properties of the nodal gap membrane.