Hanging - Medical Effects

Medical Effects

A hanging may induce one or more of the following medical conditions, some leading to death:

• Closure of carotid arteries causing cerebral ischemia
• Closure of the jugular veins
• Induction of carotid sinus reflex death, which reduces heartbeat when the pressure in the carotid arteries is high, causing cardiac arrest
• Breaking of the neck (cervical fracture) causing traumatic spinal cord injury or even decapitation
• Closure of the airway
• Death erection

The cause of death in hanging depends on the conditions related to the event. When the body is released from a relatively high position, the major cause of death is severe trauma to the upper cervical spine. However, the injuries produced are highly variable. One study showed that only a small minority of a series of judicial hangings produced fractures to the cervical spine (6 out of 34 cases studied), with half of these fractures (3 out of 34) being the classic "hangman's fracture" (bilateral fractures of the pars interarticularis of the C2 vertebra). The location of the knot of the hanging rope is a major factor in determining the mechanics of cervical spine injury, with a submental knot (hangman's knot under the chin) being the only location capable of producing the sudden, straightforward hyperextension injury that causes the classic "hangman's fracture".

There is evidence suggesting that there might be superior alternatives if there were sufficient interest to support research into such matters. Consider in particular an event recounted in the biography of Albert Pierrepoint. Events followed a most unconventional sequence during the hanging of a particularly powerful and uncooperative German spy during World War II. Pierrepoint relates: "Just as I was crossing to the lever, he jumped with bound feet. The drop opened, and he plunged down, and I saw with horror that the noose was slipping. It would have come right over his head had it not caught roughly at a point halfway up the hood – it had in fact been stopped on his upper lip by the projection of his nose – and the body jerked down, then became absolutely still apart from the swinging of the rope. I went down into the pit with the prison medical officer. He examined the body and said to me: "A clean death. Instantaneous." He sounded surprised, and I did not blame him. I was surprised myself, and very relieved. On my next visit to Wandsworth the governor told me that the severance of the spinal cord had been perfect."

Not surprisingly in retrospect, it appears that such unconventional application of forces might be particularly efficient. There is at least some evidence that some of the countries with particularly active programs of judicial execution may have given the question of the design of efficient and reliable nooses practical attention. For example, photographs of nooses in a South African execution chamber opened to the public after abolishment of the death penalty, showed double nooses. Presumably the upper noose held the lower one in place to ensure a perfect hangman's fracture. The possibly more elegant, but probably more tricky English technique with a single running noose and a rope so arranged as to whip around into the ideal position, might well have been too error-prone to be satisfactorily reliable in any but highly skilled hands. If so, the likes of the double noose might have much merit.

The side, or subaural knot, has been shown to produce other, more complex injuries, with one thoroughly studied case producing only ligamentous injuries to the cervical spine and bilateral vertebral artery disruptions, but no major vertebral fractures or crush injuries to the spinal cord. Death from a "hangman's fracture" occurs mainly when the applied force is severe enough to also cause a severe subluxation of the C2 and C3 vertebra that crushes the spinal cord and/or disrupts the vertebral arteries. Hangman's fractures from other hyperextension injuries (the most common being unrestrained motor vehicle accidents and falls or diving injuries where the face or chin suddenly strike an immovable object) are frequently survivable if the applied force does not cause a severe subluxation of C2 on C3.

Another process that has been suggested is carotid sinus reflex death. By this theory, the mechanical stimulation of the carotid sinus in the neck brings on terminal cardiac arrest.

In the absence of fracture and dislocation, occlusion of blood vessels becomes the major cause of death, rather than asphyxiation. Obstruction of venous drainage of the brain via occlusion of the internal jugular veins leads to cerebral edema and then cerebral ischemia. The face will typically become engorged and cyanotic (turned blue through lack of oxygen). There will be the classic sign of strangulation, petechiae, little blood marks on the face and in the eyes from burst blood capillaries. The tongue may protrude.

Compromise of the cerebral blood flow may occur by obstruction of the carotid arteries, even though their obstruction requires far more force than the obstruction of jugular veins, since they are seated deeper and they contain blood in much higher pressure compared to the jugular veins. Only 31 newtons (7 lbf or 3.2 kgf) of force may be enough to constrict the carotid arteries to the point of rapid unconsciousness. Where death has occurred through carotid artery obstruction or cervical fracture, the face will typically be pale in color and not show petechiae. Many reports and pictures exist of actual short-drop hangings that seem to show that the person died quickly, while others indicate a slow and agonizing death by strangulation.

When cerebral circulation is severely compromised by any mechanism, arterial or venous, death occurs over four or more minutes from cerebral hypoxia, although the heart may continue to beat for some period after the brain can no longer be resuscitated. The time of death in such cases is a matter of convention. In judicial hangings, death is pronounced at cardiac arrest, which may occur at times from several minutes up to 15 minutes or longer after hanging. During suspension, once the prisoner has lapsed into unconsciousness, rippling movements of the body and limbs may occur for some time which are usually attributed to nervous and muscular reflexes. In Britain, it was normal to leave the body suspended for an hour to ensure death.

After death, the body typically shows marks of suspension: bruising and rope marks on the neck. Moreover, sphincters will relax spontaneously and urine and faeces will be evacuated. Forensic experts may often be able to tell if hanging is suicide or homicide, as each leaves a distinctive ligature mark. One of the hints they use is the hyoid bone. If broken, it often means the person has been murdered by manual choking.