title: Teres minor muscle and related anatomy.
abstract: BACKGROUND
  The purpose of this study was to describe the complex anatomy surrounding the teres minor muscle.
  
  
  METHODS
  Thirty-one cadaveric human shoulders were dissected. Qualitative fascial and neurovascular anatomy were described. Location of motor nerves to teres minor were measured in reference to local anatomy.
  
  
  RESULTS
  Fascial anatomy of the posterior shoulder had 2 distinct and equally common variants, 1 of which demonstrated a stout, inflexible fascial compartment enveloping the teres minor muscle. The other had a continuous fascia enveloping both the infraspinatus and teres minor muscles. In both variants, the primary nerve to teres minor traveled around a fascial sling, becoming sub-fascial at an average of 44 mm (range, 25-68) medial to the teres minor's insertion. The nerve took its most angulated course as it entered the fascial sling. Smaller accessory innervation of teres minor began, on average, 30 mm (range, 15-48) medial to the muscle's lateral insertion. None of the accessory motor nerves coursed deep to the fascial sling nor to the distinct teres minor fascial compartment.
  
  
  CONCLUSIONS
  A stout fascial sling may be the potential site of greatest compression and tethering of the primary motor nerve to teres minor. Additional lateral accessory motor nerves to teres minor remained extra-fascial and took a less angulated path. Half of the shoulders demonstrated a separate teres minor fascial compartment. An improved understanding of the fascial anatomy and innervation pattern of the teres minor muscle may help clinicians who treat patients with symptomatic isolated teres minor muscle atrophy.
authors.affiliation: Southwest Shoulder, Elbow and Hand Center, Tucson, AZ, USA.
authors.forename: Dara
authors.initials: D
authors.lastname: Chafik
authors.forename: Leesa M
authors.initials: LM
authors.lastname: Galatz
authors.forename: Jay D
authors.initials: JD
authors.lastname: Keener
authors.forename: H Mike
authors.initials: HM
authors.lastname: Kim
authors.forename: Ken
authors.initials: K
authors.lastname: Yamaguchi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017006:Rotator Cuff / Q000033:anatomy & histology*