title: Prediction of the location of the anterior branch of the axillary nerve, using correlations with physical factors: a cadaveric study.
abstract: BACKGROUND
  Although axillary nerve injury is a catastrophic surgical complication, there is little data for precise prediction of the location of that nerve's anterior branch. To address that, the authors searched for a useful correlation between the acromion-axillary nerve distance (AAND) and one or more physical factors.
  
  
  METHODS
  The heights, humeral lengths, AAND, and axillary nerve indexes (ANI: ratio between AAND and humeral length) of 25 male and 20 female cadavers were determined. Any gender differences in the mean measurements were determined. The correlations of each AAND with height, humeral length, and ANI were determined. The authors determined that using the ANI and the humeral length allowed the shortest prediction of the AAND.
  
  
  RESULTS
  The mean AAND, cadaver height, and humeral length were 6.5 ± 0.8, 164.9 ± 10.0, and 33.5 ± 2.7 cm, respectively. An independent t test revealed significant gender differences in the mean AAND (P = .003), height (P = .000), and humeral length (P = .000), but not in the mean ANI (P = .564). The Pearson coefficients for the associations of the AAND with height (r = .767), humeral length (r = .797) and ANI (r = .732) demonstrated strong correlations (P < .001), especially with humeral length. The use of the ANI with the humeral length yielded the shortest predictions of AAND, with a 97.8% probability of safety.
  
  
  CONCLUSIONS
  There is a strong correlation between AAND and humeral length. In clinical practice, humeral length and ANI are useful for predicting the location of the anterior branch of the axillary nerve, when the arm is positioned at the side in neutral rotation.
authors.affiliation: Department of Orthopaedic Surgery and Institute of Health Sciences, School of Medicine, Gyeongsang National University, Jinju, South Korea.
authors.forename: Chang-Meen
authors.initials: CM
authors.lastname: Sung
authors.forename: Gu Seob
authors.initials: GS
authors.lastname: Roh
authors.forename: Hyun-Joon
authors.initials: HJ
authors.lastname: Sohn
authors.forename: Hyung Bin
authors.initials: HB
authors.lastname: Park
mesh_terms: D000174:Acromion / Q000033:anatomy & histology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001132:Arm / Q000294:innervation; D001917:Brachial Plexus / Q000033:anatomy & histology*; D002102:Cadaver; D005260:Female; D006801:Humans; D006811:Humerus / Q000033:anatomy & histology*; D008297:Male; D008875:Middle Aged; D012782:Shoulder / Q000294:innervation; D055815:Young Adult
keywords: Anatomy; Anterior branch; Basic Science Study; Cadaver Dissection; acromion-axillary nerve distance; axillary nerve; gender; height; humeral length