Reverse Total Shoulder Arthroplasty for Acute Proximal Humerus Fractures: Is Delay Associated With an Increased Rate of Reoperation?

OBJECTIVES: To compare reoperation rates of acute versus delayed reverse total shoulder arthroplasty (RTSA) following a period of nonoperative treatment for proximal humerus fractures (PHFs). We also aimed to identify an optimal time interval from PHF to RTSA before the risk of reoperation significantly increased. METHODS: Design: Database review. Setting: Ontario, Canada. Patient Selection Criteria: Adults aged 50 years and older who sustained a PHF (OTA/AO 11A-C) between 2004 and 2019 were included. Exclusion criteria included polytrauma, open fractures, non-Ontario residents, invalid health insurance, and any operative treatment before RTSA. Outcome Measures and Comparisons: The primary outcome measure was reoperation within 2 years following RTSA. A risk-adjusted, restricted cubic spline was used to model the probability of reoperation according to the time elapsed between PHF and RTSA to identify a time point at which the risk of reoperation significantly increased. A multivariate logistics regression was used to identify predictors. RESULTS: In total, 891 patients (685 acute, 206 delayed) underwent RTSA for PHF. The acute cohort had a significantly lower reoperation rate (3.9%) compared with the delayed cohort (8.3%) (P = 0.02). The odds of reoperation increased with a delay to RTSA greater than 28 days and continued to rise until 100 days after fracture. Patients who underwent RTSA 28 days after PHF were found to have a significantly higher odds of reoperation by 2 years (P = 0.03). CONCLUSIONS: Among patients undergoing RTSA for acute PHFs, a delay to surgery greater than 28 days is associated with a greater odds of reoperation and may be useful when counseling patients.