Comparison of Clinical Outcomes Between Primary and Salvage Reverse Shoulder Arthroplasty for Proximal Humeral Fractures: A Retrospective Study.

OBJECTIVE

This study provides a comparative analysis of clinical outcomes between primary and salvage reverse shoulder arthroplasty (RSA), offering valuable insights into the management of proximal humerus fracture (PHF). To evaluate the outcomes of patients treated with RSA as a primary procedure for acute PHF and to compare these with patients undergoing salvage RSA as a revision procedure for fracture sequelae of PHF.

METHODS

A retrospective cohort study was conducted on 42 patients undergoing RSA for PHF between December 2014 and April 2022. The primary RSA group (n = 28, mean age 73.8 ± 4.5 years, 66-81 years) included patients with acute fractures, while the salvage RSA group (n = 14, mean age 62.1 ± 12.3 years, 47-83 years) comprised revision cases for fracture sequelae. Active range of motion (ROM), Visual Analog Scale (VAS), Constant score, and American Shoulder and Elbow Surgeons (ASES) scores were assessed for all patients. Outcomes between the two groups were compared, along with radiographic outcomes and complications recorded at each follow-up. Categorical variables were analyzed using chi-square or Fisher's exact tests, while continuous variables were compared using independent t-tests or Mann-Whitney U tests based on data distribution.

RESULTS

At a mean follow-up of 56 months (24-106 months), no significant differences in gender (p = 0.469) or follow-up duration (p = 0.087) were observed. The salvage group exhibited comparable postoperative ROM (anterior flexion (AF): 101.4° ± 52.3° vs. 115.9° ± 29.1°; external rotation (ER): 26.4° ± 16.4° vs. 28.8° ± 14.1°; internal rotation (IR): 7 ± 2 vs. 7 ± 2; all p > 0.05) and clinical scores (VAS: 1.6 ± 1.9 vs. 1.2 ± 1.5; Constant: 74.1 ± 23.3 vs. 79.4 ± 15.9; ASES: 81.9 ± 15.4 vs. 84.0 ± 13.8; all p > 0.05) to the primary group. However, the salvage group demonstrated significant preoperative-to-postoperative improvements in AF (50.9°, p < 0.001), ER (5.4, p = 0.017), and functional scores (VAS: -4.6; Constant: + 36.9; ASES: + 45.8; all p < 0.05). Complications occurred in 14.3% of salvage cases (2 revisions for periprosthetic fracture and aseptic loosening) versus 3.6% in the primary group. No other major complications such as deep infection, instability, acromial stress fracture, or dislocation were recorded.

CONCLUSION

RSA achieves comparable functional and radiographic outcomes for both acute PHF and fracture sequelae over 4 years of follow-up. Salvage RSA provides substantial clinical improvement but carries a higher complication risk, emphasizing the need for meticulous surgical technique and patient selection.