Hip dislocations and concurrent injuries in motor vehicle collisions.

Introduction: Motor Vehicle Collisions (MVC) can cause high energy hip dislocations associated with serious injury profiles impacting triage. Changes in safety and regulation of restraint devices have likely lowered serious injuries from what was previously reported in the 1990s. This study aims to describe modern-day injury profile of patients with traumatic hip dislocations, with special attention to aortic injury.

Methods: Retrospective review of a prospectively maintained trauma database at an urban level 1 trauma center was conducted. Patients with hip dislocation following MVC between January 2005 and December 2015 were grouped based on seatbelt use and airbag deployment. Patients with unknown restraint use were excluded. Multiple logistic regression was used to identify risk of injury profile between groups.

Results: Of 204 patients with hip dislocation after MVC, nearly 57% were unrestrained. Seatbelt alone was used in 36 (17.7%), airbag deployed in 14 (6.9%), and 38 (18.6%) with both. Gender and number of injuries were similar between groups. The most common concomitant injury was acetabular fracture (53.92%) and the abdominopelvic region was the most injured. Use of a seatbelt with airbag deployment was protective of concomitant pelvic ring injury (OR = 0.22). Airbag deployment was significantly protective of lumbar fracture (OR = 0.15) while increasing the likelihood of radial and ulnar fracture or dislocation (OR = 3.27), acetabular fracture (OR = 5.19), and abdominopelvic injury (OR = 5.07). The no restraint group had one patient (0.80%) with an intimal tear of the thoracic aorta identified on CT chest that was successfully medically managed.

Discussion And Conclusion: Hip dislocations are high energy injuries with severe associated injuries despite upgrades in restraint devices. These patients require careful examination and heightened awareness when evaluating for concomitant injuries.