title: Correlation between subclinical median neuropathy and the cross-sectional area of the median nerve at the wrist.
abstract: Although subclinical median neuropathy is not uncommon, its correlation with sonographic changes to the median nerve at the wrist has not been studied. We included 62 subjects (with 107 wrists) who reported experiencing no hand numbness. All subjects underwent nerve conduction studies (NCS) and sonography for median nerve at the pisiform level. The cross-sectional area (CSA), perimeter, long axis and short axis of median nerve were obtained off-line by manual tracing with a mouse and computed by one algorithm written in MatLab. Eighteen wrists met the inclusion criteria of subclinical median neuropathy. The CSA, perimeter and long axis of the median nerve were significantly different between normal and abnormal NCS wrists. Mixed model analysis showed that subclinical neuropathy was associated with enlarged CSA, but the other demographic variables (gender, age and body mass index and occupational categories) were not. Our findings support the use of both patient symptoms and NCS to define normal subjects during further studies. In addition, enlarged CSA within asymptomatic individuals should raise concern for subclinical median neuropathy.
authors.affiliation: Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan, Republic of China.
authors.forename: Po-Hsien
authors.initials: PH
authors.lastname: Su
authors.forename: Wen-Shiang
authors.initials: WS
authors.lastname: Chen
authors.forename: Tyng-Guey
authors.initials: TG
authors.lastname: Wang
authors.forename: Huey-Wen
authors.initials: HW
authors.lastname: Liang
mesh_terms: D000293:Adolescent; D000328:Adult; D019412:Anatomy, Cross-Sectional / Q000379:methods*; D002349:Carpal Tunnel Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008475:Median Nerve / Q000000981:diagnostic imaging*; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D014463:Ultrasonography / Q000379:methods*; D014953:Wrist / Q000000981:diagnostic imaging* / Q000294:innervation*; D055815:Young Adult