Pigs
Heart Lesions Demonstrated in Crash Study
P. Löwenhielm , G. E. Voigt, C. B. A. Ljung and B. G. WihlbergDivision of Solid Mechanics Institute of Technology, Department of Forensic Medicine University of Lund/Sweden, Lund/, Sweden
Received: 4 February 1977
Summary:
Belt protected car occupants involved in head-on collisions do not seem to suffer as severe injuries as unembalmed cadavers subjected to comparable simulated head-on collisions. Therefore it has been questioned if cadavers constitute adequate test specimens for study of thoracic tolerances. This investigation compares injuries in safety belt wearing living and dead pigs which have been subjected to simulated head-on collisions on an acceleration track. Tests were performed on all 20 pigs (10 living and 10 dead). The arterial side of the circulatory system of the dead pigs was infused. The force in the safety belts, the intraaortic pressure, the impact velocity and the deceleration of the sled were recorded. The tests were high speed filmed. Post mortem examination of the pigs revealed differences in injury severity. Dead pigs more easily suffered rib fractures. Deformation of the rib cage due to stripping of the periosteum and laceration of surrounding tissue occurred mainly in the dead pigs. Laceration of intrathoracic blood vessels was seen in dead pigs while isolated heart lesions were seen only in living animals. The main cause of these differences in tolerance level seems to be post mortem changes of the mechanical properties of the different tissues.
The results are valid for pigs but indicate that great care has to be exercised when results obtained from cadaver experiments are evaluated concerning thoracic tolerance.
Key words:
Thoracic tolerance, head-on collisions using pigs – safety belts, head-on collision experiments – traffic medicine, head-on collision experiments, thoracic tolerance in dead and living pigs