[Distribution of motor nerve conduction velocities in the ulnar nerve--a control study, its clinical application and limitations].
The goal of measuring the conduction velocity of a peripheral nerve is to describe the distribution of conduction velocities (DCV) of each nerve fiber in a nerve bundle examined. The author devised a fully automatized method to describe the DCV of a nerve bundle with a signal processor. The principle of the method is nerve impulse collision method which was devised by Hopf in 1963. DCV of the ulnar nerve innervating the first dorsal interosseous muscle from the elbow to the wrist was examined in sixty five normal subjects without any evidence of peripheral nerve problems, in ninety seven patients with diabetes mellitus (DM) and in five normal subjects whose forearm was cooled. Maximum conduction velocity at the same region was measured by using conventional method and compared to the DCV. In control group, there was very mild influence of aging on the peak velocity of DCV but there was no statistically significant deference of mean DCV pattern between any decade of age. In this group a bimodal distribution of velocities was demonstrated. It is assumed that the distribution represents populations of motor fibers innervating the fast and the slow twitch muscle fibers in this muscle. Those results in patients with DM and those normal subjects with their forearm was cooled were controversial. In patients with DM the peak velocity of DCV and its density has positive correlation, in contrast those cold injury group has negative correlation. It might be represents that the pathological condition of large fiber loss in the former group and small fiber damage in the latter group.(ABSTRACT TRUNCATED AT 250 WORDS)
Tachibana
S
S
Department of Neurosurgery, School of Medicine, Kitasato University, Sagamihara, Japan.
D000328:Adult; D003929:Diabetic Neuropathies / Q000503:physiopathology; D004594:Electrophysiology / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology*; D009431:Neural Conduction; D012016:Reference Values; D012881:Skin Temperature; D014459:Ulnar Nerve / Q000502:physiology*