Strangulation (z7714)

STRANGULATION (strangulatio), or suffocation, a type of asphyctic death in which the neck is compressed by a ligature or a hand. Strangulation by a ligature differs from hanging in that the noose on the neck is tightened not by the weight of the body, as in hanging, but by an external or one's own hand. Strangulation by ligature is most often murder and significantly less often suicide. Accidental strangulation can also occur: for example, a female worker being strangled by a headscarf worn around the neck, the ends of which get caught in the moving parts of a machine. The ligature, which can be made of any material (rope, men's garter, necktie, etc.), is tied with one or more knots or (which is observed in self-strangulation) the tied ligature is additionally twisted with an inserted stick, splinter, etc. Semenov recommends paying attention to the material from which the ligature is made, the position of the knot (in front, on the side in suicide), and the number of turns of the ligature (numerous turns of the ligature or several separate loops one over another indicate self-strangulation). It is clear that these signs are not absolute and have significance in the aggregate of others. The strangulation furrow in strangulation is located, as a rule, not above the larynx, but on it or even lower. The furrow goes circularly around the neck, lying in a horizontal direction. The appearance (width, color, density) of the furrow depends on the material from which the ligature is made, the pressure force, and the duration of the ligature's presence on the neck. With a soft ligature and its short duration, the strangulation furrow may be absent. Among other signs of strangulation, one should point out pronounced cyanosis of the face, and sometimes the neck, with a large number of petechiae, and petechiae in the conjunctivae. Autopsy reveals hemorrhages in the muscles of the neck along the course of the furrow and above it in the region of the floor of the mouth, tongue, pharynx, in the cellular tissue along the trachea and esophagus. Fractures of the horns of the thyroid cartilage, the hyoid bone, and the cartilages of the larynx are encountered, especially in elderly persons. Extensive damage to the soft tissues of the neck and the cartilages of the larynx has diagnostic significance in the sense of excluding self-strangulation. The absence of any damage does not exclude murder. Trial strangulation by hand is always murder. Among the external signs, besides facial cyanosis and petechiae, numerous round or crescent-shaped abrasions should be noted—traces of the pressure of fingernails and fingers when grasping the neck with the hands. In strangulation with one hand, the abrasions are few, especially on the side where a single finger was located. If pressure on the neck was exerted through some soft object (scarf, kerchief), there may be no abrasions on the neck at all. The abrasions are located on the anterior and lateral surfaces of the neck throughout the entire extent from the edge of the lower jaw. At autopsy, damage to the muscles and cartilages of the larynx is more constant and more extensive than in ligature strangulation. Fractures of the horns and even the cartilages of the larynx are frequent. Hemorrhages may sometimes be located only in the immediate vicinity around the larynx and trachea, being absent in the superficial muscles. The mechanism of death in strangulation is the same as in hanging (see), i.e., apart from compression and closure—in most cases incomplete—of the airways, the compression of vessels and nerves is of great importance. Asphyxia in strangulation proceeds more slowly than in hanging. The possibility of death from shock caused by pressure on the larynx and neck nerves, e.g., the vagus, is not excluded.