Total, trabecular, and cortical bone mineral density in different regions of the glenoid

The purpose of this study was to analyze total, trabecular, and cortical bone mineral density (BMD) of different regions of the glenoid. Soft tissue was dissected from 20 cadaveric shoulders, and the glenoids were isolated. Axial peripheral quantitative computed tomography (pQCT) scans perpendicular to the articular surface were performed at the middle level of each (superior, middle, and inferior) horizontal third of the glenoid, and the total, trabecular, and cortical BMDs of the anterior and posterior half of each region were determined by use of pQCT software. The total BMDs of the posterior and superior glenoid were significantly higher than those of the anterior and inferior glenoid (P < .01). Trabecular BMD of the posterior glenoid was significantly higher than that of the anterior glenoid, and cortical BMD of the superior glenoid was significantly higher than that of the inferior glenoid (P < .01). These significant differences in distribution of the BMD explain previous findings of the mechanical properties of the glenoid. Future glenoid component design should provide maximal surface area for posterior and superior bone ingrowth to the component. Posteriorly and superiorly, the glenoid bone stock also provides stronger support for any kind of fixation on the bony surface.