Open fractures of the lower leg: Outcome and risk-factor analysis for fracture-related infection and nonunion in a single center analysis of 187 fractures.

Background: Open fractures of the lower extremity have a higher risk of fracture-related infections (FRI) or nonunion. The purpose of this study was to identify risk factors for complications and evaluate outcomes.

Methods: In this retrospective, single center study, we identified and included 187 patients with extraarticular and intraarticular fractures of the tibia or fibula between 2010 and 2018. Patient characteristics, treatment protocols, and complications were assessed, with a focus on soft tissue management and timing of wound closure versus fracture fixation. To analyze risk factors for FRI and nonunion, a univariate logistic regression model was used.

Results: The open fractures included were 52 Gustilo-Anderson type-I (28 %), 99 type-II (53 %), and 36 type-III (19 %) fractures. The mean time from admission to first surgical intervention was 3.47 h (SD 1.4), with 122 (60 %) patients treated within 3 h and 182 (97 %) patients, within 6 h. During primary surgery, definitive fracture fixation was carried out in 112 (60 %) patients and wound closure in 122 (65 %) patients. FRI was reported in 27 (14 %) patients with the highest prevalence in type-III fractures (31 %). Secondary wound closure was associated with a significantly higher risk for FRI than primary wound closure (odds ratio [OR] = 3.3; p = 0.004). Nonunion was reported in 37 (20 %) patients. Significant risk factors for nonunion were FRI (OR=11.9, p < 0.001) and definitive fracture fixation before wound closure compared to fracture fixation and wound closure at the same time (OR = 8.2, p < 0.001). Gustilo-Anderson type-IIIb and -IIIc fractures had a significant lower FRI-free survival compared to other fractures. No patient underwent amputation during the follow-up.

Conclusions: Open fractures of the tibia and fibula are associated with a high risk of FRI and nonunion. FRI is the strongest predictor of nonunion in open fractures of the lower extremity. Primary wound closure and simultaneous definitive fracture fixation are protective even in higher Gustilo-Anderson fracture types and prevent complications. Early antibiotic therapy and surgical treatment are crucial, as evidenced by all cases receiving treatment within 6 h post trauma.