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Affiliation
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Department of Surgery, University of Cincinnati, Cincinnati, OH, USA; Harborview Medical Center, University of Washington, Seattle, WA 98104, USA. |
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Abstract
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Pneumatic nail guns have been used by the construction industry for nearly 45 years and since their inception there have been numerous reports of injuries sustained as a direct result of nail gun use. Most injuries are not life threatening and result in isolated puncture wounds to the hand or fingers. However, even these presumed minor injuries are associated with significant social and economic effects since the majority of these injuries result in significant amount of lost work. Currently it is estimated that pneumatic nail gun injuries occur at a rate of 0.26 cases per 200,000 work hours and account for 3.9% of workers' compensation claims.
Nail guns are divided into low-velocity and high-velocity tools. High-velocity nail guns are characterized by a speed greater than 150 m/s and require an explosive cartridge to propel the nail. Low-velocity nail guns are characterized by a speed less than 150 m/s and rely on compressed air or a cartridge to fire a piston resulting in the firing of the nail. The energy delivered from these devices varies greatly, but ranges between 100 and 1000 J. Due to the poor stabilization of the tool, tumbling of the nail projectile is common. As a result of these many different factors, pneumatic nail gun injuries present in a variety of ways. Many reported cases are accidental, but there are reports of self-inflicted purposeful injuries. Due to the potential devastation associated with these injuries, most nail guns now have safety features that prevent misfiring.
Although this penetrating cardiac injury is associated with a projectile similar to a gunshot wound, the relatively low mortality rate is more characteristic of the mortality rate of stab wounds compared to gunshot wounds. This is most likely due to the nail projectile's limited kinetic energy and relatively small impact force resulting in little diffusion of energy.
Although most of these injuries do not result in death, tool safety and prevention remains important in the work place. In the last several years, significant improvements in the safety features of pneumatic nail guns have been made. Currently, pneumatic nail guns require that a pressure gradient be applied to a surface of greater than 100 Newstons prior to firing. It is thought that this particular safety feature is associated with a significant reduction in the number of accidental injuries resulting in a reduction in the inadvertent non contact firing of a nail projectile. However, this feature alone, as demonstrated in the case presented, does not complete remove the risk of accidental injury. |