title: Proximity of Axillary Nerve During Cortical Button Repair of Pectoralis Major Tendon Rupture.
abstract: BACKGROUND
  Rupture of the pectoralis major (PM) tendon is a rare but severe injury. Several techniques have been described for PM fixation, including a transosseus technique, placing cortical buttons at the superior, middle and inferior PM tendon insertion points. The present cadaveric study investigates the proximity of the posterior branch of the axillary nerve to the drill positions for transosseus PM tendon repair.
  
  
  METHODS
  Twelve cadaveric shoulders were used. The axillary nerve was marked during a preparatory dissection. Drills were passed through the humerus at the superior, middle and inferior insertions of the PM tendon and the drill bits were left in situ. The distance between these and each axillary nerve was measured using computed tomography.
  
  
  RESULTS
  The superior drill position was in closest proximity to the axillary nerve (three-dimensional distance range 0-18.01 mm, mean 10.74 mm, 95% confidence interval 7.24 mm to 14.24 mm). The middle PM insertion point was also very close to the nerve.
  
  
  CONCLUSIONS
  Caution should be used when performing bicortical drilling of the humerus, especially when drilling at the superior border of the PM insertion. We describe 'safe' and 'danger' zones for the positioning of cortical buttons through the humerus reflecting the risk posed to the axillary nerve.
authors: Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK.
authors: Sarah T
authors: ST
authors: Lancaster
authors: Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK.
authors: Geoff C
authors: GC
authors: Smith
authors: Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK.
authors: Oluwafunto E
authors: OE
authors: Ogunleye
authors: Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK.
authors: Damian A
authors: DA
authors: Clark
authors: Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK.
authors: Iain N
authors: IN
authors: Packham
keywords: Axillary nerve; axillary nerve injury; cadaveric study; pectoralis major; transosseus repair