The shape of the inferior part of the glenoid: a cadaveric study.

Previously, the shape of the inferior glenoid has been described as a circle with a bare spot being the center of that circle. This cadaveric study was done to test that statement. Forty cadaveric scapulae were used in this study. Two researchers used a digital image analysis program to assess the shape of the inferior glenoid and measured the distances from the bare spot to the anterior, inferior, and posterior cartilage and the bone rim. In 39 of 40 scapulae, the inferior glenoid had the shape of a true circle. Statistical analysis showed that the center of the bare spot is not the mathematical center of the inferior glenoid, but the differences in distances to the anterior, inferior, and posterior rims were very small (1.16-2.41 mm). Both observations can be used for further development of methods for measuring glenoid bone loss in patients with anterior glenohumeral instability.