Maxillofacial injuries in moose-motor vehicle collisions versus other high-speed motor vehicle collisions.

The severity of motor vehicle collisions involving large cloven-hoofed animals has been previously described. These animals (moose, elk and deer) have long legs, and consequently, the height from the ground to the undersurface of the abdomen is generally above the hood of an automobile. Thus, in a collision, the automobile knocks the legs out from under the animal, sending the body over the vehicle hood toward the windshield, front pillars and roof of passenger cars (1). This typically results in a rear and downward deformation of the windshield pillars and front roof (2). Anecdotal experience has suggested that there is a higher frequency of maxillofacial injury among occupants of motor vehicles in collisions involving moose. Several published reports (1–5) from the United States, Canada and Sweden describe the injuries sustained by occupants of motor vehicles that collide with moose, elk or deer. These studies, all case series, report that between 43% and 70% of the victims’ injuries involved the head or face. A case series (3) of moose-motor vehicle collisions in northern New England between 1990 and 1994 reported on 23 subjects, 70% of whom sustained head and/or face injuries. A case series (5) of fatalities due to collisions between motor vehicles and cloven-hoofed animals (mostly moose) in Sweden between 1976 and 1981 revealed that in 60 of 63 cases, the injuries involved the head or neck. While some of these authors speculated that the distribution of injuries from game accidents differed from those of other types of motor vehicle accidents, this has not yet been specifically addressed in the existing literature. All of these studies were case series and none compared motor vehicle collisions involving moose with other motor vehicle collisions. We therefore conducted a retrospective cohort study comparing the incidence of various injury types in moose-motor vehicle collisions with other high-speed motor vehicle collisions. The study was carried out at the Foothills Medical Centre in Calgary, Alberta, which serves as the regional trauma centre for southern Alberta. The geography of Alberta varies from the Rocky Mountains in the western part of the province to the prairies in the east. As of September 1997, there were approximately 232,000 white-tailed deer, 133,000 mule deer, 118,000 moose and 26,000 elk in Alberta (6).