Clinical outcomes of cemented vs. uncemented reverse total shoulder arthroplasty for proximal humerus fractures: a systematic review

Background Reverse total shoulder arthroplasty is an established treatment method for comminuted proximal humerus fractures. Both cemented and uncemented techniques exist, with uncemented reverse total shoulder offering many theoretical advantages, including improved biologic fixation, absence of cement related complications, and ease of revision if necessary. There are few studies comparing the outcomes of the two techniques. Methods The study was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A search for studies assessing clinical outcomes of reverse total shoulder arthroplasty for proximal humerus fractures was performed of PubMed, Embase, Web of Science, and Cochrane Library. Main outcomes included Constant Score (CS), American Shoulder and Elbow Surgeons (ASES) score, and complication rate. Inclusion criteria were as follows: indication for arthroplasty was fracture; minimum one year follow up; article in English. Exclusion criteria were as follows: review articles; biomechanical or cadaver studies. Quality analysis was performed using the Cochrane Risk of Bias tool (RoB 2) and the Risk of Bias in Non-randomized Studies-of Interventions (ROBINS-I) tool. Results A total of 682 studies were identified through the initial search, with 36 studies meeting all inclusion criteria. There were 24 studies investigating cemented technique, 10 studies examining uncemented technique, and two studies involving both techniques. There was no difference in mean follow up between patients receiving a cemented vs. uncemented rTSA (32.3 months vs. 30.6 months, p = 0.06). Patients who received a cemented rTSA had a significantly higher Constant-Murley score than those who received an uncemented rTSA (59.4 vs 55.9, p < .001). There was no difference between the two groups when comparing ASES Scores (77.5 vs 78.6, p = 0.54) and overall complication rates (11.1% vs 11.8%, p = 0.23). Conclusion Both cemented and uncemented rTSA are both valid options for treating acute proximal humerus fractures. Cemented rTSA may portend slightly improved clinical outcomes with similar overall complication rates compared to uncemented rTSA for proximal humerus fractures.