Author/Authors :
Kieser، David Christopher نويسنده Department of Surgical Sciences, Dunedin School of Medicine, Division of Health Sciences, University of Otago, Dunedin, New Zealand , , Riddell، Riley نويسنده Department of Surgical Sciences, Dunedin School of Medicine, Division of Health Sciences, University of Otago, Dunedin, New Zealand , , Kieser، Julius August نويسنده Sir John Walsh Research Institute, University of Otago, Dunedin, New Zealand , , Theis، Jean-Claude نويسنده Sir John Walsh Research Institute, University of Otago, Dunedin, New Zealand , , Swain، Michael Vernon نويسنده Sir John Walsh Research Institute, University of Otago, Dunedin, New Zealand ,
Abstract :
Skeletal fractures produced by bullet impacts are unique and yet their mechanism remains poorly understood. To understand the initiation and propagation of direct ballistic skeletal fractures on cylindrical bones. We observed the effect of 9 mm spherical non-deforming steel projectiles fired at increasing velocities of 10 ft/s (3 m/s) to 200 ft/s (60 m/s) (pre-impact kinetic energy of 0.013-5.35 J) directly upon skeletally mature deer femora. Skeletal damage was assessed following micro-computed tomography and fluorescent microscopy. A cascade of injury severity was identified, with fractures first seen at a pre-impact kinetic energy of 1.08 J and progressing from localized micro-fragmentation and indentation to long radiating fractures. Bone indentation was found to increase with increasing projectile speed. The deformation and resultant fracture process occurs as a reproducible cone crack cascade with an expanding zone of fragmentation. This knowledge should aid clinicians in understanding the formation of fracture fragments, the forces exerted on these fragments and the areas of residual weakness to ensure optimal skeletal management.
