title: Utility of the cutaneous silent period in the evaluation of carpal tunnel syndrome.
abstract: OBJECTIVE
  This study investigates the utility of the cutaneous silent period (CuSP) in evaluating patients with carpal tunnel syndrome (CTS).
  
  
  METHODS
  The authors measured the CuSP from the abductor pollicis brevis muscle in 135 hands of patients with idiopathic CTS and 30 hands of age- and gender-matched controls. The patient group was further divided into subgroups according to the Canterbury scale. The differences in parameters between the patient subgroups and control group were analysed. A predetermined analysis looked at the possible correlation between the CuSP and symptom severity as measured by the Boston-Questionnaire.
  
  
  RESULTS
  The mean CuSP latencies in the patient group (72.4+/-16.1 ms) was significantly longer than the control group (64.6+/-13.4 ms; P=0.014), although there was no difference in the duration of the CuSP between groups. The duration and latency of the CuSP correlated to a higher severity on the Canterbury scale (r=0.273, P<0.001 and r=-0.164, P=0.036, respectively). However, the CuSP parameters did not correlate with the Boston-Questionnaire scores.
  
  
  CONCLUSIONS
  Although patients with CTS had significantly prolonged CuSP latency, the CuSP did not correlate with the clinical symptoms scale.
  
  
  CONCLUSIONS
  The CuSP is a useful ancillary test to evaluate Adelta fibre function; however, it is not a reliable tool to quantify clinical severity.
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Yong Seo
authors.initials: YS
authors.lastname: Koo
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Ha-Rim
authors.initials: HR
authors.lastname: Park
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Byung-Euk
authors.initials: BE
authors.lastname: Joo
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jeong-Yoon
authors.initials: JY
authors.lastname: Choi
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Ki-Young
authors.initials: KY
authors.lastname: Jung
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Kun-Woo
authors.initials: KW
authors.lastname: Park
authors.affiliation: Department of Neurology, Stanford University Medical Center, Stanford, CA, USA.
authors.forename: S Charles
authors.initials: SC
authors.lastname: Cho
authors.affiliation: Department of Neurology, Korea University College of Medicine, Seoul, Republic of Korea. Electronic address: nukbj@korea.ac.kr.
authors.forename: Byung-Jo
authors.initials: BJ
authors.lastname: Kim
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000328:Adult; D000368:Aged; D002349:Carpal Tunnel Syndrome / Q000175:diagnosis* / Q000503:physiopathology*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology*; D012720:Severity of Illness Index; D012867:Skin / Q000294:innervation / Q000503:physiopathology*; D013223:Statistics as Topic; D011795:Surveys and Questionnaires