Abstract
Stemless shoulder arthroplasty implants for the proximal humerus provide cementless metaphyseal prosthetic fixation. A near-perfect anatomic restoration of the proximal humeral articular surface is possible with this canal-sparing design—avoiding the risks associated with humeral stems and preserving bone for later revision.
When compared with proximal humeral resurfacing, stemless arthroplasty avoids the potential technical errors that may lead to oversized implants, abnormal shift of the glenohumeral joint center of rotation, and excessive strain on the native rotator cuff.
While canal-sparing stemless implants represent a new concept in shoulder arthroplasty without mid- and long-term results, the failures associated with resurfacing humeral arthroplasty have been documented in the literature. Unlike a stemless component, use of a resurfacing technique (and hence preservation of the humeral head) makes glenoid prosthetic implantation challenging and often impossible.