Shoulder Prosthesis Mechanics

Shoulder Prosthesis

Measurements of shoulder prosthesis positioning

One of the most difficult aspects of shoulder arthroplasty is retroversion. The ideal angle is about 30 of posterior rotation of humeral head with regard to the frontal plane so that the humeral head squarely faces the glenoid surface in the resting position.The axis, lateral epicondylemedial epicondyle is often taken as reference and serves as landmark in many arthroplasty instrumentation. [1,...

Evolution of the reverse total shoulder prosthesis.

Over the last decade, reverse total shoulder arthroplasty has gained significant popularity due to its ability to address difficult reconstructive shoulder problems that could not be adequately treated in the past. The concept of the reverse shoulder prosthesis was introduced in the 1970s, but the initial attempts were associated with high complication and implant failure rates. The pioneering ...

Training protocol for a powered shoulder prosthesis.

There is a scarcity of literature on rehabilitation training protocols for upper-limb prosthesis use. Seminal textbooks and articles describe protocols for training individuals to use conventional body-powered, myoelectric, or passive prosthetic devices and were written prior to the introduction of multifunction prosthetic hands and more advanced prosthetic technologies [1–3]. Furthermore, deta...

Analysis of a retrieved delta III total shoulder prosthesis.

A reversed Delta III total shoulder prosthesis was retrieved post-mortem, eight months after implantation. A significant notch was evident at the inferior pole of the scapular neck which extended beyond the inferior fixation screw. This bone loss was associated with a corresponding, erosive defect of the polyethylene cup. Histological examination revealed a chronic foreign-body reaction in the ...