Acute reverse total shoulder arthroplasty versus internal fixation for 3- and 4- part proximal humerus fractures: A propensity matched analysis of 5466 elderly patients.

INTRODUCTION

The purpose of this study was to utilize a large national database to evaluate short- and long-term outcomes of acute management of proximal humerus fractures (PHF) with reverse total shoulder arthroplasty (RSA) compared to open reduction internal fixation (ORIF).

METHODS

The TriNetX platform was utilized to perform a retrospective review of patients who sustained PHFs treated within three weeks of injury. Patients were identified using Current Procedural Terminology codes and the International Classification of Disease diagnosis codes. The cohorts were 1:1 propensity matched. Patients who received RSA were propensity matched to patients who underwent ORIF. Short-term and long-term outcomes were compared across the cohorts across various post operative periods. Kaplan Meier survival analysis was used to analyze implant survival rate and Cox hazard ratio was used to identify risk factors of re-operation.

RESULTS

Following propensity matching, each cohort included 2733 patients with an average age of 71±9.5. Patients treated with ORIF were more likely to have a re-operation or hospital admission than patients who underwent RSA at both 1 and 2 year follow up (5.5 % vs 2.1 %; p < 0.001; 6.9 % vs 2.6 %, p < 0.001 and 13.7 % vs 11.3 %, p = 0.01; 19.6 % vs 16.4 %, p = 0.003). At two year follow up, 173 patients treated with ORIF had a re-operation of which 60 (35 %) were converted to arthroplasty. On Kaplan Meier survival analysis for re-operation, both implants had satisfactory survival rates at both one and two year time point with survival rates over 90 %. However, there was a difference between survival rates at both one and two years between the ORIF and RSA groups (94 % vs 98 %, p < 0.0001; 91 % vs 97 %, p < 0.0001). For ORIF, patients with four part PHF and osteoporosis had a 39 % and 19 % increased risk of re-operation (p < 0.001; p = 0.03).

CONCLUSION

While both ORIF and RSA have been shown to be acceptable techniques for managing PHFs in the elderly, ORIF had a significantly higher re-operation and hospital readmission rate at mid- and long-term follow up. Additionally, a large portion of patients undergoing re-operation following ORIF were converted to shoulder arthroplasty although acute RSA has superior outcomes compared to delayed RSA. Therefore, for operative elderly candidates we advocate for the use of RSA in three- and four-part PHFs.