Complications after reverse shoulder arthroplasty for proximal humerus nonunion

Area of Science:

• Orthopedic Surgery
• Musculoskeletal Research

Background:

• Proximal humerus nonunion presents a significant surgical challenge.
• Open reduction internal fixation (ORIF) and reverse total shoulder arthroplasty (RTSA) are primary surgical options.
• Previous studies indicate high complication and revision rates for RTSA in nonunion cases.

Purpose of the Study:

• To evaluate complication and reoperation rates of RTSA for proximal humerus nonunion at a single institution.
• To identify patient-specific or surgical variables associated with increased risk of complications and reoperations.

Main Methods:

• Retrospective review of 50 patients undergoing RTSA for proximal humerus nonunion (2005-2021).
• Nonunion defined as lack of radiographic union >90 days post-fracture.
• Exclusion of patients with <1 year follow-up; data collected on demographics, surgical factors, complications, and reoperations.

Main Results:

• Overall complication rate was 34% (17/50), with 20% (10/50) requiring reoperation.
• High rates of dislocation (12%) and humeral loosening (10%) were observed.
• Younger age at RTSA and diabetes mellitus were significant predictors of reoperation (P=.013, P=.037).
• Two-year survivorship free from reoperation was 73%.

Conclusions:

• RTSA can improve pain and function in selected proximal humerus nonunion patients.
• Complication and reoperation rates for RTSA in nonunion are notably high compared to other indications.
• Optimizing implant stability and fixation is crucial for RTSA in proximal humerus nonunion cases.