Designing the ideal model for assessment of wound contamination after gunshot injuries: a comparative experimental study

Barium titanate particles were distributed throughout a test chamber for an assessment of wound contamination. We fired .22-caliber Magnum bullets first into gelatin blocks and then into porcine hind limbs placed behind the chamber. Two other types of bullets (.222-caliber bullets and 6.5 × 57 mm cartridges) were then shot into porcine hind limbs. Permanent and temporary wound cavities as well as the spatial distribution of barium titanate particles in relation to the bullet path were evaluated radiologically.A comparison of the gelatin blocks and hind limbs showed significant differences (p < 0.05) in the mean results for all parameters. There were significant differences between the bullets of different calibers in the depth to which barium titanate particles penetrated the porcine hind limbs. Almost no particles, however, were found at a penetration depth of 10 cm or more. By contrast, gas cavities were detected along the entire bullet path.Gelatin is only of limited value for evaluating the path of high-velocity projectiles and the contamination of wounds by exogenous particles. There is a direct relationship between the presence of gas cavities in the tissue along the bullet path and caliber size. These cavities, however, are only mildly contaminated by exogenous particles.Gunshot injuries not only cause direct tissue damage but often also lead to contamination by foreign material along the bullets path [1,2]. The role of exogenous particles that contaminate a wound cavity and the role of non-bacterial tissue damage resulting from sterile necrosis remain controversial in the literature [3]. As a result, the ballistic effects of gunshot injuries are a matter of controversy as well [4,5]. There is, however, general agreement that high-velocity projectiles cause cavitation effects and tissue destruction and thus produce areas of tissue necrosis with different diameters radially from the bullet path [6]. In gunshot injuries, the extent of cavitation effects general