Risk factors for surgical site infection following orthopaedic surgery for fracture by trauma: a nested case-control study

Background: Surgical site infection (SSI) is associated with higher medical expenses and lower patient quality of life.

Aim: To identify specific modifiable risk factors for SSI after orthopaedic surgery for fractures caused by trauma.

Methods: This nested case-control study used a nationwide trauma registry, the Japan Trauma Data Bank (JTDB) database. Patient data from 280 hospitals between January 2004 and May 2019 were retrieved from the JTDB. Patients with SSI and identified patients without SSI as control subjects were included, using propensity score matching adjusted for unmodifiable factors. Risk factors associated with SSI after orthopaedic trauma surgery were assessed using multi-level mixed-effects logistic regression models.

Findings: In total, 15,910 patients were included in the analysis. Of these patients, 377 (2.4%) had SSI. After propensity score matching, 258 patients with SSI and 2580 matched patients without SSI were selected. In the multi-level mixed-effects logistic regression analysis, blood transfusion within 24 h (odds ratio (OR): 1.51; 95% confidence interval (CI): 1.06-2.13) was a significant risk factor for SSI following orthopaedic fracture surgery. The OR (95% CI) values for external fixation, transcatheter arterial embolization, and tourniquet for SSI following orthopaedic fracture surgery were 1.40 (0.96-2.03), 1.66 (0.81-3.38), and 2.99 (0.60-14.87), respectively.

Conclusion: These findings highlight the necessity of exercising caution when implementing blood transfusion within 24 h as a risk factor associated with SSI following orthopaedic trauma surgery.