title: Quantifying glenoid bone loss arthroscopically in shoulder instability.
abstract: OBJECTIVE
  Our goal was to establish a consistent methodology for quantifying glenoid bone loss by arthroscopic means.
  
  
  METHODS
  This study was an anatomic investigation of glenoid structure and its consistent anatomic landmarks as determined by arthroscopic means in live subjects and by direct measurement in fresh-frozen cadaver specimens.
  
  
  METHODS
  We arthroscopically evaluated and measured the location of the bare spot of the glenoid in 56 subjects that had no evidence of instability (average age, 40 years). We also measured the exact location of the glenoid bare spot in 10 cadaver shoulders (average age, 76 years).
  
  
  RESULTS
  The bare spot of the glenoid was a consistent reference point from which to determine glenoid bone loss because it was located almost exactly at the center of the circle that was defined by the articular margin of the inferior glenoid below the level of the midglenoid notch. The tightly clustered standard deviations of the bare spot measurements in both the live subjects and the cadaver specimens confirmed its consistent location.
  
  
  CONCLUSIONS
  The glenoid bare spot can be used as a central reference point to quantify the percentage bone loss of the inferior glenoid. Such objective measurement of glenoid bone loss can be clinically useful to the surgeon in deciding whether bone grafting is necessary to restore stability to the shoulder with a bone-deficient glenoid.
authors: Baylor College of Medicine, The San Antonio Orthopaedic Group, San Antonio, Texas, USA.
authors: Stephen S
authors: SS
authors: Burkhart
authors: Joe F
authors: JF
authors: Debeer
authors: Armin M
authors: AM
authors: Tehrany
authors: Peter M
authors: PM
authors: Parten
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001182:Arthroscopy / Q000379:methods*; D002102:Cadaver; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000150:complications* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000145:classification* / Q000175:diagnosis / Q000209:etiology; D012785:Shoulder Joint / Q000473:pathology*