Increased morbidity and mortality after bilateral femoral shaft fractures: myth or reality in the era of damage control?

INTRODUCTION: Bilateral femoral shaft fractures have been reported to be an independent risk factor for morbidity and mortality; however, the value of these studies is limited due to small sample sizes and the timing of these studies before the establishment of damage control orthopaedics. The objective of this study was to compare the incidence of morbidity and mortality in patients with bilateral vs. unilateral femoral shaft fractures in the era of damage control orthopaedics.
METHODS: Retrospective analysis of the TraumaRegister DGU from 2002 to 2005. Inclusion criteria were uni- or bilateral femoral shaft fractures and complete demographic data documentation. Univariate data analysis and logistic regression analysis were performed with SPSS.
RESULTS: Between 2002 and 2005, 776 patients with unilateral and 118 patients with bilateral femoral shaft fractures were identified. Patients with bilateral femoral shaft fractures had a significantly higher Injury Severity Score (ISS) (29.5 vs. 25.7 points), a significantly higher incidence of pulmonary (34.7% vs. 20.6%) and multiple organ failure (25.0% vs. 14.6%) as well as a significantly higher mortality rate (16.9% vs. 9.4%). In the overall patient population, early total care (ETC) was significantly more often performed in patients with unilateral femoral shaft fractures (50.9% vs. 33.6%). Logistic regression analysis revealed no significant association between bilateral femoral shaft fractures and multiple organ failure or mortality; however, bilateral femoral shaft fractures are an independent risk factor for pulmonary failure. Subgroup analysis revealed that the impact of the bilateral femoral shaft fracture was especially pronounced in patients with an ISS<25 points. DISCUSSION: Bilateral femoral shaft fractures are an independent risk factor for pulmonary failure but not for multiple organ failure or mortality. The impact of the additional femoral shaft fracture for pulmonary failure appears to be especially pronounced in the less severely injured patients, whose injuries are often underestimated when stratified with the ISS. Patients with bilateral femoral shaft fractures have significantly more often severe abdominal injuries as well as severe blood loss which may account for the increased mortality rate. Therefore, the presence of bilateral femoral shaft fractures should be recognised as an increased risk for systemic complications.