Pelvic Ring Fractures Are an Independent Risk Factor for Death After Blunt Trauma

Abstract

It is unknown whether pelvic ring fracture is an independent predictor of death after blunt trauma. Few previous studies have attempted to analyze whether the high death rate observed in association with pelvic ring injury is secondary to the pelvic ring injury or merely related to many other injuries that typically are sustained in such cases. Our hypothesis was that pelvic ring fracture is an independent risk factor for death, even after accounting for the risk of death from other associated injuries. We reviewed the records of 31,550 patients who presented with blunt trauma at our Level I trauma center from 1995 to 2002. We analyzed our prospectively collected database and excluded any patient who was missing more than one demographic parameter (n = 414, 1.3% of the data set). Our study group consisted of 1,017 patients with pelvic ring fractures and 30,119 patients with blunt trauma without pelvic ring fractures. Multiple logistic regression analysis was conducted to account for the relative contribution of associated clinical criteria to mortality. A mortality model was then designed by using the regression analysis, allowing us to compare a calculated chance of death for each patient in the study group. We then compared the expected number of deaths of patients with pelvic injury with the actual number of observed deaths in that data set. Additionally, we conducted a second statistical analysis with which we compared the death rate of our pelvic ring fracture population (n = 1,017) with a matched subgroup (n = 1,017) from our patient population without pelvic ring fractures (n = 30,119). The presence of pelvic ring fracture was found to be an independent risk factor for mortality in the blunt trauma population based on both statistical methods (odds ratios, 1.9 [p < 0.001] and 2.1 [p < 0.0007]). Other significant predictors of mortality included patient age, Injury Severity Score, Glasgow Coma Scale score, systolic blood pressure and respiratory rate at admission, and several medical comorbidities. The presence of pelvic ring fracture seems to represent a clinically significant independent risk factor for mortality, even after accounting for the association with potentially severe additional body system injuries.