Relationship between the dynamic parameters and injury severity of chest subject to impact

Seventeen dogs were subjected to blunt left lateral impact at velocities from 7.14 m/s to 19.05 m/s. The impacts to the thoracic wall were recorded by accelerometers fixed on the ribs at the impacted point and other areas. From this information the dynamic parameters (compression response, instantaneous deformation velocities, and viscous response) were calculated. The thoracic injury scores were recorded according to the Abbreviated Injury Scale (AIS-85). The results showed that the chest was a viscoelastic structure. The dynamic parameters of the chest wall were correlated with the physical parameters in exponential function or logarithmic function. There was a more significant relationship between viscous criterion and injury score among the various parameters. The relationship curve was sigmoid. The results indicated that the viscous response might be a valid parameter for indicating the severity of injury.