3D Full-Field Mechanical Measurement of a Shoulder Bone Under Implant Loading

The mechanics of shoulder bones under implant loading is important to the success of shoulder replacement surgery. This work presents the results of a noninvasive three-dimensional (3D) full-field mechanical measurement of implanted shoulder bones under various physiologically realistic loading conditions. A glenoid implant was cemented in a human cadaveric specimen by a shoulder surgeon and loaded in a mechanical tester coupled with micro X-ray computed tomography (micro-CT). The micro-CT images of the specimen was taken under no-load, eccentric loading, and concentric loading conditions, respectively. Using image processing technique and digital volume correlation, the 3D displacement field inside the shoulder bone were calculated. The results were displayed using 3D visualization tools. The clinical implications of the results are discussed for the improvement of total shoulder replacement.