title: Sonographic differences in carpal tunnel syndrome with normal and abnormal nerve conduction studies.
abstract: We evaluated the differences in sonographic parameters in carpal tunnel syndrome (CTS) patients with normal and mildly abnormal nerve conduction studies (NCS). This was a prospective cross-sectional study. We assessed 169 wrists (101 patients) with a clinical diagnosis of carpal tunnel syndrome (CTS), as well as 20 healthy controls (40 wrists). 49 wrists were classified as mild NCS-positive and 38 as NCS-negative based on our laboratory NCS normal values. The cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet and mid-forearm were measured and the wrist-to-forearm ratio (WFR) was calculated. 26% of the NCS-negative group had abnormal CSA. The CSA and WFR also differed significantly between the two groups. There was significant correlation between the sonographic and electrophysiologic variables. Ultrasound was diagnostic for CTS in a third of the NCS-negative wrists. Ultrasound may be useful in clinical CTS patients with normal or borderline NCS.
authors.affiliation: Australian National University Medical School, Canberra, ACT, Australia; Institute of Neurological Sciences, Prince of Wales Hospital, Sydney, NSW, Australia; Prince of Wales Clinical School, University of New South Wales, Sydney, NSW 2052, Australia. Electronic address: adeniyiborire@yahoo.com.
authors.forename: Adeniyi A
authors.initials: AA
authors.lastname: Borire
authors.affiliation: Australian National University Medical School, Canberra, ACT, Australia; Department of Neurology, The Canberra Hospital, Canberra, ACT, Australia.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Hughes
authors.affiliation: Australian National University Medical School, Canberra, ACT, Australia; Department of Neurology, The Canberra Hospital, Canberra, ACT, Australia.
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Lueck
authors.affiliation: Institute of Neurological Sciences, Prince of Wales Hospital, Sydney, NSW, Australia; Prince of Wales Clinical School, University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: James G
authors.initials: JG
authors.lastname: Colebatch
authors.affiliation: Institute of Neurological Sciences, Prince of Wales Hospital, Sydney, NSW, Australia; Prince of Wales Clinical School, University of New South Wales, Sydney, NSW 2052, Australia.
authors.forename: Arun V
authors.initials: AV
authors.lastname: Krishnan
mesh_terms: D000328:Adult; D000368:Aged; D019412:Anatomy, Cross-Sectional; D002349:Carpal Tunnel Syndrome / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D003430:Cross-Sectional Studies; D005260:Female; D005542:Forearm / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000000981:diagnostic imaging; D008875:Middle Aged; D009431:Neural Conduction; D009460:Neurologic Examination; D011446:Prospective Studies; D014463:Ultrasonography; D014953:Wrist / Q000000981:diagnostic imaging; D055815:Young Adult
keywords: Carpal tunnel syndrome; Cross-sectional area; Median nerve; Nerve conduction studies; Ultrasound