Glenoid Rim Anatomy

Methods: Three-dimensional computed tomography scans of 30 normal cadaveric specimens were obtained. A virtual model of a generic labral anchor was inserted into the rim of the glenoid at the clockface positions represented by 12:00, 1:30, 3:00, 4:30, 6:00, 7:30, 9:00, and 10:30. At each position, the safe insertion range was the maximal range measured, and the optimal insertion angle was identified as the angle between the bisector of the safe insertion range and the glenoid face. Results: Progressing in the clockwise direction, beginning at the 12:00 position, the safe insertion ranges (mean ± SD ) were 55.9 ± 10.6 , 63.6 ±17.6 , 47.7 ±9.1 , 46.1 ±8 , 73.9 ±9.7 , 40.9 ±6.5 , 40.4 ±7.4 , and 39.9 ±7.1 , respectively. The optimal insertion angles were 47.9 ± 7.6 , 53.1 ± 10.9 , 35.0 ± 4.4 , 42.4 ± 4.9 , 60.9 ± 8.4 , 36.6 ± 5.9 , 31.2 ± 4.9 , 34.8 ± 4.6 , respectively.