About chokes and strangles
Intro
Chokes and strangles are often confused since they both involve applying pressure to the neck.Chokes
Chokes apply pressure to the windpipe (trachea) to either reduce the air supply to the lungs or to damage the windpipe so the air supply will be interrupted or stopped. Pressure to the windpipe is usually applied with the forearm or some stick type object, although the thumbs or fingers may be used.Chokes can be very effective if they are applied properly and at the proper time. If you suddenly apply a choke to an unsuspecting person, it will take a relatively long time to take effect and, due to the defensive efforts of the victim during this time, the choke will probably fail. Although, if the attacker is larger in size and stronger than the victim, the choke stands a better chance of being successful. However, when a choke is applied to a person when he or she is involved in some strenuous physical activity when he or she is breathing heavily, such as during a fight, the results could be almost immediate.
Chokes can also be applied by compressing the chest and abdomen, thus preventing the opponent from inhaling. This method is often used during pinning techniques when you apply your body weight to a prone opponent’s chest causing him or her to use the abdomen for breathing. Then you shift some of your weight to the opponent’s abdomen, effectively stopping his or her ability to breath. When used in combination with windpipe choke or a strangle, a compression choke may increase their effectiveness.
Cutting off or reducing respiration may bring about changes of a reflex nature that can cause serious heart and respiratory reactions. It may cause an inadvertent valsalva maneuver (forced expiration with the glottis closed), which will set in motion other reflex changes and cardiovascular effects resulting in dangerous and even irreversible physiologic changes.
Strangles
Strangles are applied to one or both carotid arteries to cut off or reduce blood flow, and thus oxygen supply, to the brain thus causing the person to feel faint or pass out. The forensic literature says that to kill a person by interrupting blood flow to the brain, you need to hold pressure for a minimum of two minutes, although the person may blackout much sooner. If a strangle is applied to a person under stress during a struggle, it may make the person unconscious almost immediately, whereas it may take several seconds for a calm person to pass out. Reay and Eisele's 1983 article in the American Journal of Forensic Pathology "Death from law enforcement neck holds" states that with the judo-derived police carotid sleeper hold, blood flow to the head is reduced by an average of 85% in about six seconds.Pressure to a carotid artery is applied to the lateral side of the neck, which the anatomists call the "carotid triangle." This triangle is formed by the midline, anteriorly (front) from the apex of the chin to the upper part of the sternum (breastbone), superiority (above) by the line formed by the lower border of the mandible (lower jaw bone) and posteriorly (behind) by the anterior border of the sternocleidomastoid muscle (strap muscle between the clavicle and to the bone of the skull behind the ear). In the center of this triangle are the common carotid artery and its branches, the carotid bodies, internal jugular vein, vagus nerve and its branches, superior laryngeal nerve, and cervical sympathetic trunk.
Overlying this superior carotid triangle is only skin and superficial fascia, which is usually thin, although there may be an appreciable amount of subcutaneous fat; there are no strong muscles to protect this area. Within the superficial fascia is the paper-thin platysma muscle, which begins in the tela subcutaneous over the upper part of the thorax, passes over the clavicle (collarbone), and runs upward and somewhat medially in the neck and across the mandible to blend with superficially located facial muscles. The platysma muscle has no important purpose, but it will wrinkle the skin of the neck transversely and it helps to open the mouth; it doesn’t protect the underlying vital structures.
To strangle a person, pressure is applied directly to these structures. This pressure may come from pressing the fist or forearm these structures, or from pulling the collar of any clothing tight around these structures. Very often, a strangle may use pressure that is applied using the distal end of the radius and the wrist to compresses the soft structures of the neck. A neck pressure of 250 mm of Hg(mercury) or 5 kg of rope tension is required to occlude carotid arteries. The amount of pressure to collapse the windpipe is six times greater.
Sources
- Koiwai, E. K. (1999). How Safe is Choking in Judo?
- Ohlenkamp, Neil. (1995). Principles of Judo Choking Techniques. [Online]. Available: http://Judoinfo.com/chokes.htm [2004, December 31]. Used with permission.
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