Gender differences in glenoid anatomy: an anatomic study.

Gender differences in glenoid anatomy have not been well studied in the current literature. Previous literature demonstrates a mismatch between glenoid anatomy and glenoid implants for shoulder replacements. This may have clinical implications in that glenoid loosening after shoulder arthroplasty has been cited as a frequent cause of poor performance of shoulder implants, and perhaps the most common indication for revision. The purpose of this study was to determine any gender differences in the size and overall shape of the glenoid. Eleven measurements were taken of 363 human scapular bone specimens (equal proportions of females to males and blacks to whites). Glenoid height and width, glenoid notch location, and depth were measured for each specimen using calipers. In addition, the authors developed a classification system to describe anterior glenoid notch morphology. There was a significant difference between female and male specimens for each dimension measured (P < 0.05). Height to width ratios were also significantly different comparing men to women (P < 0.05). These differences resulted in a rounder male glenoid and more oval female glenoid. Our results showed that 80.4% of females had an anterior glenoid notch compared to only 57.6% of males. There was a significant difference between female and male specimens in the location of the anterior glenoid notch: 36.7% from the top of the glenoid in female specimens, and 28.9% in males (P < 0.0001). The clear difference between male and female glenoid anatomy may be important in various shoulder surgeries.