Electrical excitation of skeletal muscle for the estimation of time since death in the early postmortem period

Electrical excitability of the Orbicularis oculi muscle was assessed on 34 cadavers, according to the subjective grading of muscular response developed by Kline and Kline. In the first group of 28 cadavers, electrical excitation was done to investigate its relationship with the time since death. Direct electrical excitation was through the use of needle electrodes to provide 50 V direct current impulses of lams duration at 50 cycles/sec. From electrical excitation of the first group of 28 cadavers, it was found that there was significant negative correlation between the degrees of muscular response and the postmortem interval, and that there was a linear relationship between the two variables. Visible electrical excitation could be elicited up to the 8^th hour after death for which the range of estimates of the postmortem interval for each degree of response have been calculated. For the second group of cadavers, it was found that electrical excitation was able to predict the actual postmortem interval for 5 out 6 cadavers within one standard error of the predicted value. The limitations and advantages of this method are discussed. It is concluded that electrical excitation of the orbicularis oculi muscle can be of practical use for estimating the time since death for appropriate cases in the early postmortem period.