Predictors for infection severity for open tibial fractures: major trauma centre perspective

Open diaphyseal tibial fractures are the most common long-bone fractures and require a rapid approach to prevent devastating complications. Current literature reports the outcomes of open tibial fractures. However, there is no robust, up-to-date research on the predictive indicators of infection severity in a large open tibial fracture patient cohort. This study investigated the predictive factors of superficial infections and osteomyelitis in open tibial fractures.

A retrospective analysis of the tibial fracture database was carried out from 2014 to 2020. Criteria for inclusion was any tibial fracture including tibial plateau, shaft, pilon or ankle, with an open wound at the fracture site. Exclusion criteria included patients with a follow-up period of less than 12 months and who are deceased. A total of 235 patients were included in our study, of which 154 (65.6%), 42 (17.9%), and 39 (16.6%) developed no infection, superficial infection, or osteomyelitis, respectively. Patient demographics, injury characteristics, fracture characteristics, infection status and management details were collected for all patients.

On multivariate modelling, patients with BMI > 30 (OR = 2.078, 95%CI [1.145-6.317], p = 0.025), Gustilo-Anderson (GA) type III (OR = 6.120, 95%CI [1.995-18.767], p = 0.001), longer time to soft tissue cover (p = 0.006) were more likely to develop a superficial infection, and patients with wound contamination (OR = 3.152, 95%CI [1.079-9.207], p = 0.036), GA-3 (OR = 3.387,95%CI [1.103-10.405], p = 0.026), longer to soft tissue cover (p = 0.007) were more likely to develop osteomyelitis. Univariate analysis also determined that risk factors for superficial infection were: BMI > 35 (OR = 6.107, 95%CI [2.283-16.332], p = 0.003) and wound contamination (OR = 2.249, 95%CI [1.015-5.135], p = 0.047); whilst currently smoking (OR = 2.298, 95%CI [1.087-4.856], p = 0.025), polytrauma (OR = 3.212, 95%CI [1.556-6.629], p = 0.001), longer time to definitive fixation (p = 0.023) were for osteomyelitis. However, none of these reached significance in multivariate analysis.

Higher GA classification is a significant risk factor for developing superficial infection and osteomyelitis, with a stronger association with osteomyelitis, especially GA 3C fractures. Predictors for superficial infection included BMI and time to soft tissue closure. Time to definitive fixation, time to soft tissue closure, and wound contamination were associated with osteomyelitis.