|The lateral vascular neck restraint|
A Chokehold (Stranglehold or in Judo referred to as shime-waza, 絞技, "constriction technique") is a grappling hold that strangles the opponent, and may lead to unconsciousness or even death. Chokeholds are used in martial arts, combat sports, self-defense, law enforcement and in military hand to hand combat applications. They are considered superior to brute-force manual strangling, which generally requires a large disparity in physical strength to be effective. Rather than using the fingers or arms to attempt to crush the neck, chokeholds effectively use leverage such as figure-four holds or collar holds that use the clothes to assist in the strangle. Depending on the reaction of the victim, it may compress the airway, interfere with the flow of blood in the neck, or work as a combination of the two (see General).
The terminology used varies. In most martial arts, the term 'chokehold' or 'choke' is used for all types of grappling holds that strangle. This can be misleading since, except for air chokes, there is rarely any actual choking (with choking meaning "to have severe difficulty in breathing because of a constricted or obstructed throat or a lack of air"). In Judo terminology, blood chokes are referred to as 'strangleholds' or 'strangles' while air chokes are called 'chokeholds' or 'chokes'. In forensics the terms 'strangle' and 'stranglehold' designate any type of neck compression, while in law-enforcement they are referred to as 'neck holds'.
An air choke or tracheal choke specifically refers to a chokehold that compresses the upper airway (trachea, larynx or laryngopharynx), hence interfering with breathing, and leading to asphyxia. Although less effective at inducing unconsciousness than its vascular counterpart, the air choke causes excruciating pain and air hunger, and in combat sports a fighter will usually submit to such a submission hold. Air chokes have been associated with fractures of the larynx or hyoid bone, and are considered less safe than blood chokes to practice. The common law-enforcement bar arm choke is an air choke done by placing the forearm across the front of the neck from behind. The free hand grabs the wrist and pulls back the forearm, hence driving the forearm (usually the radius bone) into the front of the neck.
A blood choke or carotid restraint, also known as a sleeper hold, refers to a chokehold that compresses one or both carotid arteries and/or the jugular veins without compressing the airway, hence causing cerebral ischemia and a temporary hypoxic condition in the brain. A well applied blood choke may lead to unconsciousness in a matter of seconds. Compared to traditional manual strangulation, properly applied blood chokes require little physical strength, and can be applied successfully by a smaller person. Blood chokes can be fatal.
The "blood choke" is currently used by numerous police departments in the USA. Some departments consider it a choice when lethal force is justified; however, it has experienced a resurgence in popularity with law enforcement since close examination of statistical data has revealed the carotid artery submission technique to be relatively safe. A study conducted by the Canadian Police Research Center and posted by the Force Science Research Center in the USA stated 52.9% of the uses left the offender uninjured, 41% sustained minor injuries and less than 6% required minor outpatient procedures. There were no recorded incidents of hospitalization or fatalities and the injuries were considered incidental to the application of the technique.
Most chokeholds featured in combat sports and martial arts are blood chokes, although some air chokes or combinations occur as well. Blood chokes, especially the rear naked choke (mata leão), triangle chokes, or gi chokes, are commonly used as submission holds in Brazilian Jiu-Jitsu. In Judo, chokeholds, known as shime-waza, are used but are often subject to restrictions based on age or rank. Chokeholds are not allowed in Sport Sambo but are allowed in Combat Sambo. The chokeholds used in Catch wrestling are the inspiration for the "chokeholds" in modern professional wrestling performances. Due to the effectiveness of chokeholds and their popularity in a wide variety of martial arts, they are often used to force submissions in mixed martial art and submission grappling competitions.
The lateral vascular neck restraint (also called sleeper hold) was once a widely taught blood choke in law enforcement, and was performed from behind by putting an arm around the neck with the crook of the elbow over the midline of the neck. By pinching the arm together while assisting with the free hand, the carotid arteries and jugular veins were compressed on both sides of the neck. This hold did not put any pressure on the airway, but an improperly applied hold could quickly turn into an air choke if the person being strangled resisted the hold by attempting to turn around.
Due to risks of fatal injuries, all American law enforcement agencies discourage, restrict, or forbid its use. The Los Angeles Police Department, for example, prohibited its officers from using air chokes and restricted use of the carotid hold to instances where death or serious bodily injury was threatened, after routinely using chokeholds for many years.