Energy, as the resultant of the components of weight and velocity, represents the real damaging quality, striking force, or “punch” of a projectile, with a variation in wound effect as the energy is distributed over the surface of the body, through the cross-sectional area and the form of the point of the projectile, and the elements of construction which a affect the preservation of its shape. As the energy is expressed in the formula,
E = WV2 ,
2g
it is evident that the increase or decrease of the velocity factor gives greater variation than the increase of weight.
Range is important only as indicating the amount of remaining energy which may be known to reside in the projectile at any stage of its flight. Without reference to the ballistic condition (velocity, weight, form, and construction, etc.) of a particular projectile, range has no surgical significance. To the military surgeon, however, it is a term of the greatest interest when these ballistic conditions are known, as it gives him a very definite indication of the remaining energy or the damaging effect of a projectile at the different stages in its flight.
The remaining energy of the American “Springfield,” or German “S” bullet, for instance, will pass it through the bodies of two men at 2,000 yards and an energy of 8 kilogram-meters, which remains at about twice that distance, will cause a disabling wound.
Wound infections are more rare in campaign in the more sparsely settled and rough countries with soldiers of the more primitive class, simple domestic habits, and greater natural resistance.
Wound treatment should be primarily directed toward the control of infection with only secondary regard for the correction of deformities which should follow as a secondary measure after resolution is established.
All treatment should be based on principles applied in the following order:
(1) Life saving.
(2) Restoration of function.
(3) Economy of the patient.
Amputation should be very rare.