Summary

There has been a significant increase in the utilization of preoperative CT as compared to MRI for RSA

Abstract

Background

In order to avoid implant related complications related to glenosphere malposition, there has been an increased interest in the use of advanced threedimensional (3D) computed tomography (CT) and magnetic resonance imaging (MRI) for preoperative planning and patient-specific instrumentation for reverse shoulder arthroplasty (RSA). While recent literature has demonstrated improved component position when this technology is applied, the clinical benefits remain largely hypothetical and unproven. Thus, the goals of the current study were to utilize a national database to describe current trends in the use of preoperative 3D imaging and investigate the relationship between such imaging and postoperative complications compared to matched controls without any preoperative imaging.

Methods

Patients undergoing RSA for non-fracture indications were identified within the Mariner dataset within the PearlDiver database from 2010-2018Q2. Patients who underwent preoperative advanced imaging (MRI and/or CT) within a year prior to surgery were then identified as study cohorts. A matched cohort undergoing RSA without preoperative advanced imaging was created for comparison purposes. The incidence of imaging over time and rates of loosening/osteolysis, periprosthetic fracture, prosthetic dislocation, and revision shoulder arthroplasty of all groups were compared using a regression analysis.

Results

The percentage of patients who underwent preoperative CT (141% increase, p < 0.0001), and either MRI or CT (107% increase, p = 0.002) increased significantly during the study period, while there was no significant increase in MRI utilization ( p = 0.122). Patients who underwent preoperative CT experienced significantly lower rates of revision shoulder arthroplasty (2.4% vs 3.3%, OR = 0.72, p = 0.004) and periprosthetic dislocation (2.8% vs 3.3%, OR 0.80, p = 0.039) within two years of RSA compared to patients who did not undergo preoperative CT, while preoperative MRI was associated with significantly lower rates of periprosthetic fracture (0.2% vs 0.4%, OR 0.44, p = 0.005), revision shoulder arthroplasty (2.1% vs 2.6%, OR = 0.75, p = 0.006), and periprosthetic dislocation (2.5% vs 3.2%, OR 0.78, p = 0.003) within two years of RSA compared to patients without an MRI.

Conclusion

There has been a significant increase in the utilization of preoperative CT as compared to MRI for RSA during the time period studied. The utilization of preoperative advanced imaging may be associated with a significant reduction in multiple implant related complications following RSA for non-fracture indications.