Unusual bone injury in a direct lightning strike: review of a witnessed lightning-related death

Introduction: Lightning strikes are a rare but often fatal natural phenomenon. A single strike can contain an energy level of 30 million volts, 50000 amperes, accompanied by an explosive thunder effect. Mechanisms of lightning injury are categorized as electrothermal effects- including direct strike, contact potential, side flash, step voltage, and upward streamer current- or the sixth mechanism known as pressure blast wave barotrauma.
Case Report: A 38-year-old lady was struck by lightning while crossing an open paddy field, an event witnessed by her daughter. The autopsy revealed torn clothing, superficial dry burns on the body, singeing of hair, and a split on the scalp with an associated linear skull bone fracture.
Conclusion: The blunt force trauma observed in this case is explained by the sixth mechanism (pressure blast wave barotrauma). The lightning bolt channel temperature is approximately 25000 K (24727ºC). According to Charles’ law, this extreme temperature causes a rapid expansion of air, resulting in a sudden increase of pressure, equivalent to a 10 kg TNT (2,4,6-Trinitrotoluene) explosion, generating a cylindrical-shaped pressure shock wave. This pressure shock wave is responsible for the torn clothing and blunt force trauma, either directly or as a result of a fall.