Midterm results of stemless shoulder arthroplasty: a prospective study

Background: This study evaluated the functional and radiologic results of shoulder arthroplasty using a single type of stemless humeral head implant with a minimum follow-up of 5 years.

Methods: Stemless shoulder arthroplasties in 78 patients at a mean age of 58 years were prospectively evaluated at a mean clinical and radiologic follow-up of 72 months. Functional results were documented using the age- and sex-adjusted Constant score with standardized radiographic examination.

Results: The Constant score improved significantly from 38.1% to 75.3% (P < .0001). Active range of motion improved significantly for flexion (from 114° to 141°), abduction (from 74° to 130°), and external rotation (from 25° to 44°; P < .0001). Bone mineral density was reduced in 34.9% of the older population, without an influence on shoulder function (Constant score without lowering of bone density; 73%; Constant score with lowering of bone density 80%; P = .404). The overall complication rate was 12.8%, with an overall revision rate of 9%. None of the stemless implants were revised for loosening.

Conclusion: The functional and radiologic results of the stemless shoulder arthroplasty are comparable to the third and fourth generation of standard stem arthroplasty.