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 degrees to 141 degrees), abduction (from 74 degrees to 130 degrees), and external rotation (from 25 degrees to 44 degrees; 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. (C) 2015 Journal of Shoulder and Elbow Surgery Board of Trustees.