title: Orthodromic sensory conduction along the ring finger in normal subjects and in patients with a carpal tunnel syndrome.
abstract: The purpose of the present study was to examine the value of measuring sensory conduction along the median and ulnar nerves of the fourth finger in the diagnosis of a carpal tunnel syndrome (CTS). In 23 controls, sensory conductions along median and ulnar nerves were identical. In 28 of 38 patients with CTS, stimulation of the ring finger revealed a reduced conduction velocity along sensory median nerve fibres in contrast to normal conduction along ulnar sensory nerve fibres. In 5 patients, a sensory action potential was absent over the median nerve and in another 5 sensory conduction was normal along both nerves. We conclude that testing of sensory conduction along the ring finger is useful in about 74% of patients with CTS, while in the remaining 26% other fingers must be examined to establish the diagnosis.
authors.affiliation: Laboratory of Clinical Neurophysiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: M
authors.initials: M
authors.lastname: Lauritzen
authors.forename: R
authors.initials: R
authors.lastname: Liguori
authors.forename: W
authors.initials: W
authors.lastname: Trojaborg
mesh_terms: D000328:Adult; D000368:Aged; D002349:Carpal Tunnel Syndrome / Q000503:physiopathology*; D004576:Electromyography; D005260:Female; D005385:Fingers / Q000294:innervation*; D005542:Forearm; D006225:Hand; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000503:physiopathology; D008875:Middle Aged; D009132:Muscles / Q000503:physiopathology; D009431:Neural Conduction; D011930:Reaction Time; D012016:Reference Values; D012677:Sensation / Q000502:physiology*; D014459:Ulnar Nerve / Q000503:physiopathology; D014953:Wrist