title: Anatomy and surgical landmarks for the ansa pectoralis: application to pectoralis major nerve selective neurotomy.
abstract: BACKGROUND
  Ansa pectoralis neurotomy is a surgical approach in the treatment of the pectoralis major muscle spasticity causing an attitude in adduction and internal rotation of the shoulder.
  
  
  OBJECTIVE
  To establish the anatomical landmarks allowing an easier localisation of the ansa pectoralis during neurotomy.
  
  
  METHODS
  Fifteen adult human cadavers (10 embalmed and 5 fresh) were dissected in order to determine anatomical landmarks allowing an easier localization of the ansa pectoralis during neurotomy.
  
  
  RESULTS
  In all the cadavers, the lateral pectoral nerve arose from the lateral cord of the brachial plexus, 0.2 cm above to 1.5 cm below the inferior border of the clavicle with a mean distance of 0.76 cm for left and right side, whereas the medial pectoral nerve arose from the medial cord of the brachial plexus, 0.7-2.3 cm below the inferior border of the clavicle with a mean distance of 0.61 cm for the left side and 0.68 cm for the right side. We systematically found both the origin of pectoral nerves and the ansa pectoralis at the level of the middle third of the distance between the sternoclavicular and the acromioclavicular joints. Moreover, ansa pectoralis was constantly localized lateral to the thoracoacromial artery. In four cases, the division of the lateral pectoral nerve was not found. In one case, medial pectoral nerve did not exist.
  
  
  CONCLUSIONS
  Ansa pectoralis can be found by a curved incision made at the mid-third of the distance between the sternoclavicular and the acromioclavicular joints, the medial point being located just below the lower edge of the clavicle and the lateral point 2 cm below the inferior edge of the clavicle.
authors: Laboratoire d'Anatomie et d'Organogenèse, Université de Picardie Jules Verne, Amiens, France. maud2602@hotmail.fr
authors: Maud
authors: M
authors: Creze
authors: Johann
authors: J
authors: Peltier
authors: Eric
authors: E
authors: Havet
authors: Arnaud
authors: A
authors: Potier
authors: Michel
authors: M
authors: Lefranc
authors: Pascal
authors: P
authors: Foulon
authors: Daniel
authors: D
authors: Le Gars
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures; D010369:Pectoralis Muscles / Q000033:anatomy & histology* / Q000294:innervation* / Q000601:surgery; D013900:Thoracic Nerves / Q000033:anatomy & histology* / Q000601:surgery