Glenohumeral Joint Osteoarthritis is Not Associated with Clavicle Fractures in a Large Arthroplasty Cohort

Introduction: A recent study based on a large osteological collection reported an association between clavicle fractures and osteoarthritis of the glenohumeral joint. No clinical study has yet addressed this potential association. Other radiographic parameters such as the critical shoulder angle have been associated with the risk of glenohumeral joint osteoarthritis. The primary outcome of this study was to determine if there is an association between glenohumeral joint arthritis and clavicle fractures. The secondary outcome was to determine the as-sociation between critical shoulder angle and glenohumeral joint arthritis in our patient cohort.Methods: We retrospectively analysed 572 consecutive shoulder arthroplasty surgeries. Osteoarthritis was the indication for 343 shoulder arthroplasties. 229 shoulder arthroplasties were performed due to another diagnosis such as trauma or fracture, cuff arthropathy, or revision surgery. Three fellowship trained consultant shoulder surgeons assessed the pre-and post-operative radiographs of all patients.Results: A clavicle fracture was suspected in 5/343 (1.5 %) shoulder arthroplasties performed due to osteoar-thritis and 5/229 (2.1 %) shoulder arthroplasties performed for another diagnosis. Interobserver variability was assessed using a Fisher Exact test and showed no significant relationship between osteoarthritis and a fracture of the clavicle (p = 0.531). Critical shoulder angle results correlated with the previously published literature regarding critical shoulder angle and osteoarthritis and rotator cuff arthropathy. Conclusion: Clavicle fractures were not associated with glenohumeral osteoarthritis in our patient cohort of shoulder arthroplasty patients. Critical shoulder angle results were consistent with published literature. Further research in the form of prospective long term studies are needed to establish if any association exists between clavicle fractures and osteoarthritis of the glenohumeral joint.Level of evidence: Level III. Retrospective analysis.