Midterm results of stemless impaction shoulder arthroplasty for primary osteoarthritis: a prospective, multicenter study.

Background: Stemless shoulder arthroplasty using 4 open-fin press-fit anchors has been showing promising short-term clinical and radiographic results for patients' primary osteoarthritis. This prospective, multicenter study presents 5-year postoperative clinical and radiological outcomes of a stemless shoulder arthroplasty for primary osteoarthritis. Methods: Between November 2012 and December 2015, 100 patients were treated for primary osteoarthritis with the Sidus stem-free shoulder system at 7 European centers. Clinical assessment included the Constant-Murley Score, American Shoulder and Elbow Standardized Shoulder Assessment Form score, Subjective Shoulder Value, and range of motion. True anteroposterior, axial and lateral radiographs were reviewed for osteolysis, glenoid and humerus loosening, heterotopic ossification, radiolucent lines, component migration and humeral bone resorption. In addition to a Kaplan-Meier survival analysis, a comparative analysis between total shoulder arthroplasty and hemiarthroplasty was performed. Results: Seventy-one patients (36 females) with a mean age of 63.8 years (range: 47-79 years) were available for the 5-year clinical and radiographic follow-up (range: 52-79 months). There was a significant increase ( Conclusion: Patients treated with the Sidus stem-free shoulder system for primary osteoarthritis continue to achieve good clinical and radiographic results without any signs of aseptic humeral implant loosening at 5 years postsurgery.