As sequels of electric injuries, different tissues and organs can be damaged and they are based on the several mechanisms of action. In the following, the commonly involved tissues are listed together with the typical damages induced by electric injuries.
Excitation of the muscle tissue during a current flow through the body may have different consequences: muscle contractions, heart arrest, paralysis of the respiratory function or a reflex reaction which may lead to a fall from a ladder.
By stimulating a large number of muscle cells, the no-let-go phenomena can occur: while the victim touches an object energized by an alternating current with the hand the repeated (tetanic) stimulation induces a contraction of the muscles in the forearm. This leads to a strong grip of the conductor (so called freezing) which cannot be released voluntarily. Hence the flexor muscles of the forearm are stronger than the extensor muscles the fingers are flexed and preclude the release of the grip. The forces of muscle contractions can be very strong and can eventually lead to bone fracture or joint dislocation.
Specific types of cardiac arrhythmias can be the sequels of electrical injuries with different health hazards. When a sufficiently strong current flows through the human body, ventricular fibrillation can be induced in the heart by very rapid asynchronous contraction and relaxation of separate muscle fibers in the heart ventricle. As a consequence, no blood is ejected by the heart and the body is no longer supplied with blood. When the myocardial cells are not able to regain their rhythm, ventricular fibrillation leads to death, if the patient is not treated immediately with a defibrillator. During defibrillation, a single strong pulse is delivered thus forcing all myocardial cells into a uniform state of excitation after which synchronicity is regained. The probability of ventricular fibrillation increases with the duration of the current flow through the body.
Burns and deep necrosis may occur on the skin and in the underlying tissues as sequels of electrical injuries, which may lead to amputation of the affected limbs depending to the severity of the injury. The injuries at the entry and exit point of the current are called current marks. If the skin is damaged by burns leading to a loss of the skin resistance the total body resistance is considerably decreased.