title: Intraneural blood flow analysis during an intraoperative Phalen's test in carpal tunnel syndrome.
abstract: Phalen's test has been one of the most significant of clinical signs when making a clinical diagnosis of idiopathic carpal tunnel syndrome (CTS). However, it is unknown whether intraneural blood flow changes during Phalen's test in patients with CTS. In this study, an intraoperative Phalen's test was conducted in patients with CTS to observe the changes in intraneural blood flow using a laser Doppler flow meter. During Phalen's test, intraneural blood flow showed a sharp decrease, which lasted for 1 min. Intraneural blood flow decreased by 56.7%-100% (average, 78.0%) in the median nerve relative to the blood flow before the test. At 1 min after completing the test, intraneural blood flow returned to the baseline value. After carpal tunnel release, there was no marked decrease in intraneural blood flow. This study demonstrated that the blood flow in the median nerve is reduced when Phalen's test is performed in vivo.
authors.affiliation: Faculty of Medical Sciences, University of Fukui, 23-3, Shimoaizuki, Matsuoka, Eiheiji, Fukui, Japan 910-1193.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Yayama
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Kousuke
authors.initials: K
authors.lastname: Awara
authors.forename: Kenichi
authors.initials: K
authors.lastname: Takeno
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Miyazaki
authors.forename: Masafumi
authors.initials: M
authors.lastname: Kubota
authors.forename: Kohei
authors.initials: K
authors.lastname: Negoro
authors.forename: Hisatoshi
authors.initials: H
authors.lastname: Baba
mesh_terms: D000328:Adult; D000368:Aged; D002349:Carpal Tunnel Syndrome / Q000503:physiopathology*; D004568:Electrodiagnosis; D005260:Female; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000098:blood supply* / Q000503:physiopathology; D008875:Middle Aged; D009431:Neural Conduction