RT Journal Article SR Electronic T1 Perforation of fragment simulating projectiles into goat skin and muscle JF Journal of the Royal Army Medical Corps JO J R Army Med Corps FD British Medical Journal Publishing Group SP 84 OP 89 DO 10.1136/jramc-2013-000065 VO 159 IS 2 A1 Johno Breeze A1 G R James A1 A E Hepper YR 2013 UL http://militaryhealth.bmj.com/content/159/2/84.abstract AB Introduction Ballistic gelatin is the most common tissue simulant used to reproduce the penetration of projectiles into muscle but published data to support its use are primarily based on bullets, despite explosive fragments being the most common cause of injury to soldiers on current operational deployments. Published ballistic tests using animal and artificial skin and muscle tissue surrogates also lack standardisation in methodology such that limited comparisons with that of human tissues can currently be made. Method Three masses of cylindrical NATO standardised fragment simulating projectiles (FSPs) were fired at 20% ballistic gelatin and the hind thighs of a killed goat. Threshold (Vth) and V50 velocities required for skin perforation and depth of penetration (DoP) into muscle were compared with gelatin. The intercept and gradient of the linear regression lines for DoP versus velocity were compared between gelatin and goat with significance defined as p<0.05. Results V50 goat skin perforation velocities for the 0.16, 0.49 and 1.10 g FSPs were 121.1, 103.7 and 97.8 m/s, respectively. There was a significant difference in the V50 required to perforate the gelatin surface compared with goat skin for the 0.16 and 0.49 g FSPs but not the 1.10 g. There was no statistical difference in the gradients for DoP versus velocity between animal and gelatin for either the 0.16 or 1.10 g FSPs. Discussion This study has produced data for skin perforation velocities and generated algorithms describing velocity versus predicted DoP into muscle for three standardised projectiles, which will be used to improve the fidelity of future injury models. 20% gelatin was demonstrated to accurately reproduce the retardation of the 1.10 g FSPs into goat muscle but the addition of a skin simulant will be required to accurately predict DoP for FSPs less than 1.10 g.