Of special interest to American troops is a study recently completed by the commanding officer of a British medical unit in the Middle East. The officer has examined 150 consecutive cases of localized skull fractures sustained during battle, more than 90 percent of which occurred in the Western Desert, and has demonstrated the following points:

a. That a considerable area of the skull is not protected by the British (old type U.S.) steel helmet from missiles moving horizontally or upward.

b. That severe wounds of this unprotected area are common. The medical officer was unable to secure accurate data as to how many of the 150 casualties were wearing a steel helmet when injured; the available figures suggest that not more than half were wearing their helmets.

Herewith is a composite sketch (fig. 4) based on radiographic observations of the 150 fractures, considered in relation to the areas covered by the British steel helmet, by a proposed British helmet, and by the U.S. helmet M1. In this sketch, black dots show the positions of the fractures. It can be observed that of the 150 cases, 65 wounds are below the brim of the British steel helmet, whereas 85 are above. There are no skull wounds below the brim of the U.S. steel helmet. The heavy concentration of wounds in the forehead is worth noting.

Figure 4. Steel Helmets and Head Wounds.

The proportion of casualties in this series produced by high-velocity missiles (bullets) has not been determined, but it is common knowledge that not more than 10 percent of casualties with head wounds caused by high-velocity missiles live to reach the base. Fragments extracted from these cases indicate that the majority were caused by low-velocity missiles (grenade or shell fragments). These fragments usually remain within the cranium as foreign bodies. This indicates that one thickness of the skull stopped the missile; therefore, it is reasonable to assume that one thickness of a steel helmet will stop such a fragment before it injures the brain.

An additional point of interest is that a high proportion of fragments that produce head injuries travel in a horizontal or slightly inclined trajectory. Examples of such fragments are those caused by bomb burst, mortar burst, or high-explosive shells bursting on contact with the ground. Very few head injuries result from air bursts.

The American medical officer who reports the results of this study adds the following comment: "This series of cases, which are the result of actual warfare, supports the wisdom of those officers who designed the present U.S. Army steel helmet M1."