Cemented vs. cementless stems for reverse shoulder arthroplasty for proximal humerus fractures: a registry analysis with patient-reported outcomes from a level 1 trauma centre.

Background: Reverse total shoulder arthroplasty (rTSA) is being increasingly used in the treatment of comminuted or unreconstructible proximal humerus fractures. It is currently unclear if cementless rTSA have equivocal revision rates, mortality, and functional outcomes compared to cemented or cementless rTSA. Methods: Two data sources were used for this study. All rTSA performed for proximal humerus fractures between 1 January 2010 and 1 January 2020 recorded on the Australian Orthopaedic Association National Joint Replacement Registry were used to determine revision rate and mortality between cemented and cementless rTSA. Patient-reported outcome measurements, including the American Shoulder and Elbow Surgeons score, Oxford Shoulder Score, and single assessment numerical value were obtained via telephone from Royal Perth Hospital (RPH) patients between 01 January 2010 and 10 February 2021. Results: The study included 83 patients who underwent rTSA for proximal humerus fractures at RPH. There were 4335 rTSA procedures identified at other hospitals nationally. Of these, 54% of rTSA used cementless humeral stems. There was no significant difference in revision rate or mortality between cemented and cementless humeral stems adjusted for age and gender. For the RPH cohort, patient-reported outcome measurements scores included American Shoulder and Elbow Surgeons score of 65.9 (CI: 60.6-71.2), Oxford Shoulder Score of 34.6 (CI: 31.9-37.2), and single assessment numerical value of 68.8 (CI: 61.8-75.8). Conclusion: Revision rates and mortality are similar between cemented and cementless humeral stems used for rTSA for proximal humerus fractures. For appropriate patients, cementless humeral stems may be an acceptable first-line treatment for proximal humerus fractures.