Intramuscular hemorrhages in the pathway of an electric current through the body — two case reports

The diagnosis of a death by electrocution is mainly made on the basis of the external findings. The flow of electric current through the human body has specific effects on the excitable tissues, but morphological signs may be sparse or even absent [1]. The problem is further accentuated by the fact that there are no specific internal findings suggesting death by electrocution, especially in cases without any externally visible electric marks. In a few cases, however, one may occasionally find intramuscular hemorrhages which are produced by tetany-induced muscle contractions [2]. These hemorrhages are mostly seen in the skeletal muscles located in the current pathway, such as the upper limb and shoulder girdle muscles [3].

A unique case of suicide by electrocution committed by an electrician, who used coin electrodes fixed to his chest and a time switch, has been reported by Anders et al. [4]. During autopsy, a blackish linear mark was noticed on the parietal pleura of the left thoracic cavity topographically connecting the cutaneous current marks. Histologically, current- and heat-related changes, such as hypercontraction bands of the intercostal muscles and coagulative changes in the perineurium of peripheral nerves, were demonstrated. Anders et al. [5] also reported a case of suicide by electrocution in an electrical engineer who used a home-made device consisting of a connecting plug, scissors, and a magnifying glass. At autopsy, intramuscular hemorrhages were found in the skeletal muscles of the arms and the upper back. Based on the topographical distribution and microscopic pattern of the skeletal muscle alterations, the authors concluded that the hemorrhages were of vital origin and caused by current-induced tetanic muscle contractions.

Two more autopsy cases are hereby described, one relating to a right upper human limb while the other deals with a female child who died after sustaining a high-voltage electric shock. In each case, superficial and deep hemorrhages were seen in the skeletal muscles of the upper extremity that could be topographically associated with the current path in the body.

Both our cases showed intramuscular bleedings of the upper limbs with external electrocution marks. In both cases, there were no external signs of blunt injuries, and dissection did not show any bleedings in the subcutis. So, it was very likely that the bleedings were due to the electrical current.

Intramuscular hemorrhages may be the result of mechanical trauma, but also have been described in cases of drowning [6], hanging [7], hypothermia [8], electrocution [3, 4], and natural deaths from a cardiac or pulmonary cause [9]. The proposed mechanisms responsible for these hemorrhages are convulsive spasms during the asphyxiation process that cause hypercontraction, overexertion, and strain-induced rupture [6, 7]. In hypothermia-related deaths, systemic vasoconstriction, hypoxia-induced endothelial damage as well as mechanical vascular damage due to shivering have also been held responsible [8]. Tetany-induced muscle contractions are said to be responsible for rupture and bleeding into the muscle fibers in electrocutions as well [3]. These hemorrhages are described as tiny to moderately sized, confluent to strip-like bleedings, and are localized in the superficial and deep compartment muscles of the arms and forearms, the shoulder girdle, the upper back, and the intercostal muscles, thereby suggesting the path taken by the current through the body [3, 4]. However, any other external injury and any postmortem artificial bleeding have to be ruled out before proposing the lesions to be of electrical origin. This might be challenging in forensic casework.

Histological differentiation of vital (agonal) from postmortem (sustained during transportation and/or rough handling of the corpse, etc.) intramuscular hemorrhages has been evaluated in some studies, utilizing routine staining methods as well as immunohistochemistry [6, 7, 10, 11]. The findings suggestive of a vital nature of muscular hemorrhages are discoid and segmental disintegration of the muscle fibers, funnel-like concavities with empty and intact sarcolemmal tubes, and appearance of pathological longitudinal striation. A star-shaped or cobweb-like, centrifugally oriented bleeding pattern in the deep muscle fibers has been suggested to be helpful in differentiating a traumatic from a non-traumatic origin, as well as vital from postmortem bleedings [6, 7, 9]. During a retrospective analysis of 37 cases of fatal electrocutions, Karger et al. [1] provided a histological account of the intramuscular hemorrhages in selected cases. The authors found ruptures of fibers and moderate bleeding in the flexor muscles of the forearms along the current pathway.

However, the validity regarding the vitality of these alterations was doubted in another study [12]. Henssge et al. examined samples of skeletal muscle taken from 20 human corpses for estimating the time since death by looking for an idiomuscular bulge or tetanic contraction in the supravital period. Additional examination of the muscles by light microscopy revealed that the findings, previously interpreted as being of intravital origin, could also be produced post mortem [12]. The authors concluded that structural changes in the muscle fibers cannot be used as sole proof of vital mechanical or electrical traumatization and may also be produced by postmortem trauma, especially in the supravital period [12]. The non-validation of the proposed vital nature of the muscular hemorrhages/alterations in the agonal period is due to the fact that muscular tissue is excitable by a variety of mechanical, electrical as well as pharmacological stimuli for a prolonged time period in the (postmortem) supravital period (of cellular life), thereby being able to generate responses and alterations akin to vitality which are apparent on a gross as well as a microscopic level [12, 13]. So, as in other cases, histological examination may be helpful but not mandatory to distinguish vital from artificial findings.

Intramuscular hemorrhages as an internal sign of electrocution are a rarely reported finding. Anders et al. reported only two cases with intramuscular bleedings in a total of eight cases with a secured current path through the upper extremities during a period of 16 years [3]. An important problem in this context may be that layered dissection of the muscles, especially those of the limbs, is not always performed. These two case reports should indicate the need of this simple but helpful technique at autopsy of suspected electrocution deaths.