SMALL FRAGMENT WOUNDS - BIOPHYSICS AND PATHOPHYSIOLOGY

This paper considers the wounding effects of small fragments in modern warfare, Small fragment wounds may be expected to predominate on a fu ture conventional battlefield; however, studies and models of ''milita ry'' wounds have tended to focus on bullets as the wounding projectile . This paper discusses briefly the types of fragment projectile expect ed from modern munitions, It goes on to define a model for such projec tiles, and describes the interaction with soft tissue simulants, The e xtent of penetration, temporary cavitation, and contamination by forei gn material are all considered, This work with simulants is validated by experimental shots against animal tissue, A wound model in an exper imental animal is described, This model was used to investigate the he matologic, biochemical, and histologic effects of a small fragment wou nd, The effects on skin and skeletal muscle are described, By sampling at various times (up to 1 week) after wounding, the natural progress of these wounds has been ascertained, The results from 28 experimental animals, with untreated fragment wounds, are reported, The most impor tant findings are that the skin damage is very localized and that the muscle damage is limited, with little necrotic tissue in the track, Fu rthermore, the extent of the muscle damage, peripheral to the wound tr ack, improves with time, healing within a few days, provided the wound remains free from infection, There was no clinical or microbiologic e vidence of infection in those animals followed for up to 3 days, Howev er, of eight animals followed to 1 week, three developed infected woun ds, This work has implications for the management of soft tissue wound s caused by fragmentation munitions, The conventional military approac h has been to treat penetrating war wounds by exploration, debridement , excision of dead tissue, and delayed primary closure; conservative t reatment has largely been regarded as inappropriate, The work presente d here shows that the potential culture medium within the wound is sma ll and can be removed by the normal bodily responses, There is no need for surgery, provided that infection can be prevented, It may be infe rred that if bacterial colonization can be prevented in the early stag es by the timely use of antibiotics, surgery may be unnecessary, Furth er studies are planned to investigate this possibility.