An assessment of skeletal fracture patterning resulting from fatal motorcycle crashes.

Motorcycle crashes result in the deaths of hundreds of motorcyclists annually in Australia and Great Britain. To assist with investigations into the circumstances of such events, forensic practitioners may be asked to infer the context in which hard and soft tissue injuries were produced. At present, limited research exists relating to skeletal fracture patterns in motorcycle crash fatalities for forensic practitioners to compare their cases with. Therefore, this study evaluated fracture patterns across the whole-body of 200 deceased adult motorcycle riders and pillion passengers whilst considering the influence of contextual variables. Cases were obtained from the Victorian Institute of Forensic Medicine, Australia, and the East Midlands Forensic Pathology Unit, England, United Kingdom, between 2012 and 2020. Intrinsic and extrinsic variable data was gathered from medico-legal reports, while skeletal trauma data was recorded using post-mortem computed tomography scans. Descriptive statistics, modified Poisson regression and negative binomial regression were undertaken to investigate fracture patterning, including the effect of the different contextual variables. The study found skeletal trauma to be common, and often extensive, in deceased motorcyclists, with fracturing of the thorax (95%), lower limbs (69%), upper limbs (65%), and skull (64%) being particularly frequent. The variables shown to affect fracture patterning and the number of bones fractured comprised age, helmet use, impact type and object, speed and ejection status. This research may aid forensic practitioners in their investigations by facilitating an enhanced understanding of fracture patterning and causation in fatal motorcycle crashes.