title: A novel variant of the cleidocervicalis muscle with clinical implications for nerve compression/entrapment.
abstract: OBJECTIVE
  The cleidocervicalis muscle occurs in approximately 1-3 % of the population that may be confused with pathological neck masses. We describe a novel variant of the muscle and its clinical implications.
  
  
  METHODS
  This is a case report of a cleidocervicalis muscle variant identified during routine cadaveric dissection.
  
  
  RESULTS
  The muscle identified originated on the C5 vertebra and inserted on the clavicle medial to the trapezius muscle. Innervation was provided by a C6 spinal nerve branch. Notably, a branch of the supraclavicular nerve was closely associated with the muscle, raising the possibility of compression of this nerve.
  
  
  CONCLUSIONS
  Presence of a cleidocervicalis muscle should be considered in cases of shoulder pain consistent with supraclavicular nerve entrapment or compression.
authors.affiliation: Department of Neurobiology and Anatomy, West Virginia University Health Sciences Center, 1 Medical Center Drive, Morgantown, WV, 26506-9128, USA, hbillings@hsc.wvu.edu.
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Billings
authors.forename: William Charles
authors.initials: WC
authors.lastname: Sherrill
mesh_terms: D000368:Aged; D002102:Cadaver; D002572:Cervical Plexus / Q000033:anatomy & histology*; D002968:Clavicle / Q000294:innervation; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000294:innervation*; D037981:Neck Dissection; D009408:Nerve Compression Syndromes / Q000209:etiology*