# The Impact of Location on De Novo Spondylodiscitis: Regions Matter but Are Secondary to Comorbidities

## TL;DR

This study finds that spinal location affects in-hospital mortality but not readmission rates for spondylodiscitis, with comorbidities like renal failure being more critical.

## Contribution

The study reveals that spinal localization has limited impact on readmission rates, while comorbidities strongly influence outcomes in spondylodiscitis.

## Key findings

- Cervical spondylodiscitis had the lowest readmission rate compared to lumbar cases.
- In-hospital mortality varied significantly by spinal location and was strongly predicted by renal failure and age.
- Lumbar spondylodiscitis was the most common type observed in the study.

## Abstract

Background/Objectives: Primary spondylodiscitis (SD) cases surging in incidence globally remain a diagnostic and therapeutic challenge for physicians. The effect of lesion location on outcomes remains unclear. This study aims to assess the 90-day all-cause readmission rate in patients suffering from spondylodiscitis in different regions of the spine, with a secondary objective of comparing in-hospital mortality rates. Methods: Utilizing the 2020 Nationwide Readmissions Database (NRD), USA, adult patients (>18 years) were selected by diagnosis with ICD-10 codes for primary spondylodiscitis. Patients were categorized by localization into eight groups, excluding multifocal patients. Comparative analysis and logistic regressions were performed. Results: Among 5547 patients, lumbar SD was most prevalent, followed by thoracic and lumbo-sacral regions. Cervical SD had the lowest readmission rate (31.3%) and lower odds versus lumbar SD (adjusted OR = 0.73; p = 0.007). Other regions showed no significant differences. In-hospital mortality varied by location. The sacral region, renal failure, and advanced age were the strongest mortality predictors. Conclusions: While the incidence of spondylodiscitis varies by location on the spine, we found no significant differences in readmission rates across regions. However, there were substantial differences in in-hospital mortality rates. Comorbidities, particularly renal failure and advanced age, appear to outweigh spinal localization as risk factors for mortality and readmission.