Characterizing bone injuring in avalanche fatalities in the French Alps: preliminary insights from post-mortem CT scans.

Abstract

Avalanches present a significant risk in mountainous environments, frequently causing severe trauma and death. While asphyxia is often the primary cause of mortality (65-100 %), the incidence of traumatic injuries, particularly bone fractures, may be increasing due to evolving recreational practices and climate change. This study aims to characterize the distribution and types of fractures in avalanche fatalities. We conducted a retrospective study at Grenoble Alpes University Hospital from April 2023 to April 2025. It included deceased adult avalanche victims with post-mortem computed tomography (CT) scans showing at least one bone fracture. MPR, MIP, and 3D reconstructions were used for image analysis. Thirteen individuals were included (61.5 % male; mean age 37 years). The thorax was the most affected region (92 % of cases). Analysis of 265 fractured bones (79 distinct bones) showed primary fracture distribution in the thorax (52 %), spine (21 %) and skull (14 %). A strong correlation existed between external trauma signs and vital skull lesions, but vital spinal and thoracic lesions often lacked clear external indicators. These preliminary findings contribute to a better understanding of avalanche-specific bone injuries, which could optimize initial management strategies. While extremity fractures are important due to their potential contribution to non-traumatic death and ease of on-site detection, thoracic, spinal and pelvic fractures are challenging to detect in the field. Their accurate identification is yet essential for determining appropriate hospital destination. This exploratory work highlights the need for further larger-cohort studies to establish robust correlations between traumatic mechanisms and avalanche characteristics.