# Association Between Fracture Morphology and Preoperative Acute Kidney Injury in Patients with Intertrochanteric Fracture

## TL;DR

This study found that comminuted hip fractures are linked to a higher risk of kidney injury before surgery, which increases mortality.

## Contribution

The study identifies comminuted fracture morphology as an independent risk factor for preoperative acute kidney injury in hip fracture patients.

## Key findings

- Comminuted fractures had a 17.5% AKI rate versus 10.2% in simple fractures.
- Preoperative AKI was associated with a 4.56-fold increase in in-hospital mortality.
- Comminuted fracture morphology was an independent risk factor for AKI (OR 2.44).

## Abstract

Background: While postoperative acute kidney injury (AKI) in patients with hip fracture has been investigated, the relationship between fracture morphology and the incidence of preoperative AKI remains unclear. This study aimed to investigate the association between fracture morphology and the incidence of preoperative AKI, as well as its impact on in-hospital mortality and length of hospital stay. Methods: A retrospective analysis was conducted on 462 patients with intertrochanteric fractures treated at a single university hospital between January 2018 and December 2023. The fractures were categorized based on radiographic morphology into two groups: simple fractures and comminuted fractures. Preoperative AKI was diagnosed using KDIGO criteria based on serum creatinine levels measured at the time of emergency department admission. Demographic characteristics and comorbidities were collected. Clinical outcomes included time to surgery, length of hospital stay, and in-hospital mortality. Multivariable logistic regression was used to identify independent risk factors for preoperative AKI. Results: Among 462 patients, 66 (14.3%) developed preoperative AKI. The incidence of AKI was significantly higher in the comminuted fracture group than in the simple fracture group (17.5% vs. 10.2%, p = 0.037). Multivariable analysis identified comminuted fracture morphology as an independent risk factor for preoperative AKI (OR 2.44, 95% CI 1.19–5.00, p = 0.015). Preoperative AKI was also significantly associated with increased in-hospital mortality (OR 4.56, CI 1.40–14.81, p = 0.018). Conclusions: Comminuted intertrochanteric fracture is significantly associated with an increased risk of preoperative AKI. Preoperative AKI is linked to worse clinical outcomes, including higher in-hospital mortality. These findings emphasize the importance of close monitoring of renal function and proper management of AKI in comminuted fracture group.