title: Ultrasound Verification Of Safe Needle Examination Of The Rhomboid Major Muscle.
abstract: BACKGROUND
  Palpation of a thoracic rib is a common method for reducing the risk of pneumothorax during electromyographic examination of the rhomboid major muscle, but its accuracy is unknown.
  
  
  METHODS
  Two physicians palpated healthy subjects to attempt to identify the center of a rib located beneath the rhomboid major muscle. The identified location was examined with ultrasonography to examine its accuracy and the subject's anatomical depths.
  
  
  RESULTS
  Forty-four subjects (88 ribs) were studied. Palpation demonstrated a 66.3% accuracy rate, with significantly more incorrect palpations seen with greater muscle thickness (P = 0.004) and body mass index (P = 0.037), but not adipose thickness, age, or skin thickness (P > 0.05).
  
  
  CONCLUSIONS
  Palpation of the ribs in an attempt to avoid inadvertent pneumothorax while examining the rhomboid major may be inaccurate, primarily in patients with large muscle bulk. We suggest a brief ultrasound evaluation before electromyography to gauge correct needle depth. Muscle Nerve 57: 61-64, 2018.
authors.affiliation: Division of Physical Medicine and Rehabilitation, University of Utah, 590 Wakara Way, Salt Lake City, Utah, 84108, USA.
authors.forename: Daniel
authors.identifier: http://orcid.org/0000-0002-4580-1173
authors.initials: D
authors.lastname: Cushman
authors.affiliation: Division of Physical Medicine and Rehabilitation, University of Utah, 590 Wakara Way, Salt Lake City, Utah, 84108, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Henrie
authors.affiliation: Department of Physical Therapy, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Linda
authors.initials: L
authors.lastname: Vernon Scholl
authors.affiliation: Department of Physical Therapy, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Monica
authors.initials: M
authors.lastname: Ludlow
authors.affiliation: Division of Physical Medicine and Rehabilitation, University of Utah, 590 Wakara Way, Salt Lake City, Utah, 84108, USA.
authors.forename: Masaru
authors.initials: M
authors.lastname: Teramoto
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D004576:Electromyography / Q000379:methods; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D009339:Needles; D010173:Palpation; D012016:Reference Values; D015203:Reproducibility of Results; D012272:Ribs / Q000000981:diagnostic imaging; D012867:Skin / Q000033:anatomy & histology; D064171:Superficial Back Muscles / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D014463:Ultrasonography
keywords: anatomy; electromyography; landmark; pneumothorax; rib; safety