Abstract
Introduction
Proximal humerus fractures are some of the most common fractures in adults. First line treatment is typically conservative, however sequelae including nonunion and malunion are possible and can cause considerable instability, pain, and loss of function. The purpose of this systematic review was to evaluate the usage of shoulder arthroplasty as a salvage tool for proximal humerus nonunion and malunion, providing insight on its effect on various outcome measures.
Methods
In adherence to PRISMA (Preferred Reporting Items for Systematic Review) guidelines, Medline, Embase, Cochrane, and Web of Science were searched through March 2026 to include in this systematic review. Studies that evaluated the usage of shoulder arthroplasty as a salvage tool in nonunion and malunion were included. Patient demographics, procedure type, range-of-motion (ROM), complications, and surgical outcome measures including ASES, Constant Murley, VAS, and patient satisfaction were recorded and analyzed.
Results
Of the 1,960 studies identified in our search, 8 studies comprising 5,568 patients met the inclusion criteria. The mean patient age was 68.78 years and mean follow-up was 56.28 months. Of the studies included, five evaluated solely reverse shoulder arthroplasty, one with both reverse and anatomic arthroplasty, and two solely anatomic arthroplasty. Clinical outcomes improved when both preoperative and postoperative data were available. Mean Constant Murley scores increased from 19.7 to 59.45 in combined nonunion/malunion cohorts, 15 to 68 in nonunion cohorts, and 22 to 63.9 cohorts. Flexion and external rotation (ER) were the most heavily reported ROM values, included in 7 of the 8 studies. Mean gain of flexion in combined nonunion/malunion cohorts was 56.2°, 29° for nonunion, and 41° for malunion. Mean gain of ER in combined nonunion/malunion cohorts was 25.9°, 9.5° in nonunion, and 20° in malunion. The most frequent complications reported in the combined study population were dislocation (3.35%), infection (2.85%), and fracture (2.80%).
Conclusion
The findings of this systematic review suggest that shoulder arthroplasty can be an effective salvage tool in patients with nonunion and malunion of PHFs. Increases in CM scores and patient satisfaction, as well as improved ROM, give evidence for the improved quality-of-life that salvage arthroplasty can provide. This review also relayed complication rates for surgeons, showing the risks associated with the intervention. However, limited homogeneity and preoperative data across studies limit our comparisons. Future studies without these hindrances will provide more insight on how to best treat proximal humerus nonunion and malunion.