title: Normal values of median nerve cross-sectional area obtained by ultrasound along its course in the arm with electrophysiological correlations, in 100 Asian subjects.
abstract: BACKGROUND
  The objective of this study is to obtain normative cross-sectional area (CSA) values for median nerve by ultrasound at predetermined sites and correlate them with electrophysiological variables in healthy Asian subjects.
  
  
  METHODS
  The median nerve was examined ultrasonographically in 100 healthy volunteers, mean age 39 years (range, 18–75 years). CSA of the median nerve was measured at wrist, mid-forearm, mid-arm, and axilla. All subjects underwent simultaneous standardized nerve conduction studies.
  
  
  RESULTS
  The mean median nerve CSAs ± SD at the distal wrist crease was 7.2 ± 1 mm2; mid-forearm 4.8 ± 0.9 mm2; mid-arm 6.1 ± 1 mm2; axilla 5.9 ± 0.9 mm2. The CSA at the wrist was the largest compared with other levels (P < 0.001), and it increased with advancing age (P < 0.002).
  
  
  CONCLUSIONS
  These normative data show that median nerve CSA is not uniform along its length. There are differences between gender, and values increase with advancing age.
authors.forename: Lokesh
authors.initials: L
authors.lastname: Bathala
authors.forename: Pavan
authors.initials: P
authors.lastname: Kumar
authors.forename: Krishna
authors.initials: K
authors.lastname: Kumar
authors.forename: Ahammad  Basha
authors.initials: A
authors.lastname: Shaik
authors.forename: Leo H
authors.initials: LH
authors.lastname: Visser
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001132:Arm / Q000294:innervation; D001365:Axilla / Q000294:innervation; D055724:Electrophysiological Phenomena / Q000502:physiology*; D005260:Female; D005542:Forearm / Q000294:innervation; D064368:Healthy Volunteers; D006801:Humans; D007194:India; D008297:Male; D008475:Median Nerve / Q000000981:diagnostic imaging* / Q000502:physiology*; D008875:Middle Aged; D009431:Neural Conduction / Q000502:physiology*; D012016:Reference Values; D014463:Ultrasonography; D014953:Wrist / Q000294:innervation; D055815:Young Adult