The extent of muscle tissue damage following missile trauma one, six and twelve hours after the infliction of trauma, studied by the current method of debridement.

Spherical missiles with velocities around 1000 m/s were used to inflict missile trauma to one thigh of pigs. The determination of the impact and exit velocities made it possible to calculate the extent of energy transferred to the tissue. About one third of the pigs were treated surgically within one hour after the trauma, one third after a delay of 6 hours and one third after 12 hours. The surgical procedure consisted of debriding muscle tissue which showed impaired contractility and/or consistency and discoloration and/or lack of capillary bleeding - the current criteria of non-viability. The amount of debrided muscle tissue from each wound was weighed and the amount of debrided muscle tissue per joule transferred to the tissue was calculated. As compared to operations performed within one hour the average of the debrided muscle tissue per joule was greater after 6 hours delay and even still greater after 12 hours. However, the difference between the averages after 6 and 12 hours were not statistically significant.