title: Localization of the brachial plexus: Sonography versus anatomic landmarks.
abstract: OBJECTIVE
  Interscalene brachial plexus blocks are performed for perioperative management of surgeries involving the shoulder. Historically, these procedures employed anatomic landmarks (AL) to determine the location of the brachial plexus as it passes between the anterior and middle scalene muscles in the neck. In this study, we compared the actual location of the brachial plexus as found with sonography (US) to the anticipated location using AL.
  
  
  METHODS
  The location of the brachial plexus was evaluated using US and AL in 96 subjects. The distance between the two locations was measured. A multivariate analysis of variance was used to determine the significance of the difference and a 2 × 2 analysis of variance was used to compare differences in gender, height, and body mass index.
  
  
  RESULTS
  The brachial plexus was located on average 1.8 cm inferior (p = 0.0001) and 0.2 cm lateral (p = 0.09) to the location determined with AL. A significant difference was also associated with gender (p = 0.03), but not with height or body mass index.
  
  
  CONCLUSIONS
  US is a reliable method that accurately pinpoints the roots of the brachial plexus. The brachial plexus is often located inferior to the location anticipated using AL. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:411-415, 2016.
authors.affiliation: Department of Nurse Anesthesia, School of Allied Health Professions, Virginia Commonwealth University, PO Box 980226, 1200 East Broad Street, Richmond, VA, 23298-0226.
authors.forename: Christian R
authors.initials: CR
authors.lastname: Falyar
authors.affiliation: Dominion Anesthesia, PLLC, 1701 N George Mason Dr, Arlington, VA 22205.
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Shaffer
authors.affiliation: Virginia Commonwealth University, VCU Medical Center, Department of Biostatistics, PO Box 980932, Richmond, VA 23298-0032.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Perera
mesh_terms: D000293:Adolescent; D000328:Adult; D059925:Anatomic Landmarks; D001917:Brachial Plexus / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography / Q000379:methods*; D055815:Young Adult
keywords: brachial plexus; musculoskeletal sonography; neck; nerve block; peripheral nerves; ultrasound