A correlative electrophysiologic study of nerve fiber involvement in carpal tunnel syndrome using current perception thresholds.
OBJECTIVE
To relate clinical severity of idiopathic carpal tunnel syndrome (CTS) to current perception threshold (CPT).


METHODS
Subjects were 51 patients with CTS (involving 51 hands), and 50 healthy control subjects (50 hands). Involved hands were grouped into three clinical grades (mild, moderate, severe). Using a neurometer (Neurotron, Baltimore, MD), we investigated the relationship between clinical grade and CPT abnormalities.


RESULTS
In the mild CTS group, most hands showed CPT abnormalities only at 2000 Hz stimulation. The moderate group included a higher percentage of hands showing abnormalities at both 2000 and 250 Hz stimulation increased. The severe group included the highest percentage of hands with abnormal values at all frequencies tested.


CONCLUSIONS
CPT showed abnormalities appear progressively from 'higher to lower' frequency stimulations relative to the increasing severity of CTS.


CONCLUSIONS
Sensory nerve fiber dysfunction apparently begins in larger fibers, extending stepwise to smaller fibers as the clinical grade of CTS progresses.
Nishimura
Akiyo
A
Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan. akiyo@zeus.eonet.ne.jp
Ogura
Taku
T
Hase
Hitoshi
H
Makinodan
Atsushi
A
Hojo
Tatsuya
T
Katsumi
Yasukazu
Y
Yagi
Katsumi
K
Mikami
Yasuo
Y
Kubo
Toshikazu
T
D000328:Adult; D000368:Aged; D002349:Carpal Tunnel Syndrome / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D004558:Electric Stimulation / Q000379:methods; D004594:Electrophysiology / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000502:physiology*; D009431:Neural Conduction / Q000502:physiology; D012684:Sensory Thresholds / Q000502:physiology*