# Diagnostic and Invasive Colonoscopies Do Not Increase the Risk of Prosthetic Joint Infection After Reverse Shoulder Arthroplasty

## TL;DR

This study found that having a colonoscopy within a year after reverse shoulder surgery does not raise the risk of joint infection, but invasive colonoscopies may slightly increase the chance of needing further surgery.

## Contribution

The study provides new evidence that colonoscopies do not increase prosthetic joint infection risk after reverse shoulder arthroplasty.

## Key findings

- Diagnostic and invasive colonoscopies did not significantly increase the risk of prosthetic joint infection at three years post-surgery.
- Invasive colonoscopies were associated with a higher rate of all-cause revision surgery in multivariate analysis.

## Abstract

Introduction

Reverse shoulder arthroplasty (RSA) is increasingly used to manage various degenerative and traumatic shoulder conditions. Prosthetic joint infection (PJI) remains a rare but serious complication, occurring in approximately 1-4% of cases. Given that colonoscopy can cause transient bacteremia - a potential risk factor for PJI - the current study aimed to determine whether undergoing diagnostic or invasive colonoscopy within one year after RSA is associated with an increased risk of PJI or all-cause revision surgery.

Methods

A retrospective cohort study was conducted using the PearlDiver All Payer Claims Database (MARINER). Patients who underwent RSA with at least three years of follow-up were identified and stratified into three groups: a control group (no colonoscopy), a diagnostic colonoscopy group, and an invasive colonoscopy group. The colonoscopy occurred within one year after undergoing the index procedure. Demographics, including age and sex, along with comorbidity data (using the Elixhauser Comorbidity Index), were collected. The primary outcomes assessed were the incidence of PJI and the rate of all-cause revision at 3 years postoperatively.

Results

A total of 1,244 patients in the diagnostic colonoscopy group, 2,973 in the invasive colonoscopy group, and 74,309 in the control group were identified. At three years postoperatively, the incidence of PJI was not significantly different between the diagnostic (3.94% vs. 3.29%, p = 0.20) or invasive (3.8% vs. 3.29%, p = 0.13) groups compared to controls. However, while the rate of all-cause revision in the diagnostic group (7.32% vs. 7.53%, p = 0.78) did not differ significantly from controls, the invasive colonoscopy group approached statistical significance (8.48% vs. 7.53%, p = 0.05) in univariate analysis and was statistically significant in multivariate analysis (OR = 1.63, p ≤ 0.01).

Conclusion

This study found that undergoing a diagnostic or invasive colonoscopy within one year after RSA does not increase the risk of PJI at three years postoperatively. However, patients who underwent invasive colonoscopy exhibited a higher rate of all-cause revision, which was statistically significant in multivariate analysis. These findings suggest that routine colonoscopy screening should not be deferred in RSA patients due to infection concerns, but the increased risk of revision following invasive colonoscopy highlights the need for further research to determine potential underlying factors.