Shotgun wound patterns.

Abstract

Relatively little has been published in the world literature on shotgun wound interpretation and ballistics. Since only few medical centers see a large number of shotgun injuries, less experienced examiners may be misled easily hi their interpretation of such wounds, particularly with regard to estimates of distance, with grave implications as to judicial consequences. The peculiarities of the shotgun and the shot shell frequently permit more accurate range estimates than do hand weapons, especially for ranges beyond 1 ft. Choke is the most important variable factor influencing the shot scatter pattern in the average medicolegal case, whereas gauge has little effect on pattern size. The most accurate estimation of range is achieved by test firing the same gun and ammunition at varying ranges to compare the spread with the entrance wound. The wound characteristics largely depend upon the distance. Close range shots make a single punched out entrance hole that increases in size proportionally to the range until individual pellets enter the target. Concomitantly, the internal injuries vary, ranging from complete destruction of the target organ at close range to individual pellet wounds at greater distances. However, it is important to realize that pellet scatter patterns within the body may be similar in diameter in both close range and distant shots. Because of this similarity, estimation of range based upon body roentgenograms has been found to be less reliable than was believed previously and, indeed, may be very misleading. Exit wounds are very rare, even at contact range, and occur only hi tangential shots, when thinner portions of the body are injured, or with the use of large pellets (buckshot).