Three-dimensional finite element analysis of the resurfaced glenoid

To address the problem of glenoid component loosening in current shoulder replacements, three-dimensional finite element models have been developed. Three models were constructed with 8-noded brick and surface contact elements combining for over 12,000 degrees of freedom per model. Two separate load cases per model were performed typifying with a maximum compressive force at the glenoid face of 1000 N and a tensile deltoid force of 300 N.

The implantation of a glenoid component which requires removal of the cortical bone from the glenoid face eliminates tensile loading of the bone found in the natural joint. The high stiffness of the metallic implant induces stress shielding of the underlying bone and prohibits deformation (flexing) of the glenoid face. Better matching of the material properties of the implant to bone are necessary to achieve long term implant stability and fixation. (Abstract shortened by UMI.)