head injury A head injury is any injury that results in trauma to the skull or brain. The terms ''traumatic brain injury'' and ''head injury'' are often used interchangeably in the medical literature. Because head injuries cover such a broad scope of inju ...

, a coup injury occurs under the site of impact with an object, and a contrecoup injury occurs on the side opposite the area that was hit. Coup and contrecoup injuries are associated with

cerebral contusion Cerebral contusion, Latin ''contusio cerebri'', a form of traumatic brain injury, is a bruise of the brain tissue. Like bruises in other tissues, cerebral contusion can be associated with multiple microhemorrhages, small blood vessel leaks into ...

s, a type of

traumatic brain injury A traumatic brain injury (TBI), also known as an intracranial injury, is an injury to the brain caused by an external force. TBI can be classified based on severity (ranging from mild traumatic brain injury TBI/concussionto severe traumatic br ...

in which the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...

bruise A bruise, also known as a contusion, is a type of hematoma of tissue, the most common cause being capillaries damaged by trauma, causing localized bleeding that extravasates into the surrounding interstitial tissues. Most bruises occur close ...

d. Coup and contrecoup injuries can occur individually or together. When a moving object impacts the stationary head, coup injuries are typical, while contrecoup injuries are produced when the moving head strikes a stationary object. Coup and contrecoup injuries are considered focal brain injuries – those that occur in a particular spot in the brain – as opposed to diffuse injuries, which occur over a more widespread area.

Diffuse axonal injury Diffuse axonal injury (DAI) is a brain injury in which scattered lesions occur over a widespread area in white matter tracts as well as grey matter. DAI is one of the most common and devastating types of traumatic brain injury and is a major cause ...

is the most prevalent pathology of coup contrecoup. The exact mechanism for the injuries, especially contrecoup injuries, is a subject of much debate. In general, they involve an abrupt deceleration of the head, causing the

to collide with the inside of the

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...

. It is likely that

inertia Inertia is the idea that an object will continue its current motion until some force causes its speed or direction to change. The term is properly understood as shorthand for "the principle of inertia" as described by Newton in his first law ...

is involved in the injuries, e.g. when the brain keeps moving after the skull is stopped by a fixed object or when the brain remains still after the skull is accelerated by an impact with a moving object. Additionally, increased

intracranial pressure Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury ( mmHg) and at rest, is normally 7–15 mmHg for a supine adult ...

and movement of

cerebrospinal fluid Cerebrospinal fluid (CSF) is a clear, colorless body fluid found within the tissue that surrounds the brain and spinal cord of all vertebrates. CSF is produced by specialised ependymal cells in the choroid plexus of the ventricles of the ...

following a trauma may play a role in the injury.

Mechanisms

Coup injury may be caused when, during an impact, the brain undergoes

linear acceleration In mechanics, acceleration is the rate of change of the velocity of an object with respect to time. Accelerations are vector quantities (in that they have magnitude and direction). The orientation of an object's acceleration is given by th ...

and deceleration forces or rotational forces, causing it to collide with the opposite side of the skull. The injuries can also be caused solely by acceleration or deceleration in the absence of an impact. Contrecoup injury may be produced by

tensile force In physics, tension is described as the pulling force transmitted axially by the means of a string, a rope, chain, or similar object, or by each end of a rod, truss member, or similar three-dimensional object; tension might also be described as t ...

s. These forces directly disrupt

neuron A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. ...

axon An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action p ...

s, other neural and meningeal structures, and blood vessels in local or diffuse patterns, typically leading to various cellular, neurochemical and metabolic effects.

Features

Contrecoup, which may occur in

shaken baby syndrome Shaken baby syndrome (SBS), also known as abusive head trauma (AHT), is the leading cause of fatal head injuries in children younger than two years. Diagnosing the syndrome has proved both challenging and contentious for medical professionals, ...

and vehicle accidents, can cause

diffuse axonal injury Diffuse axonal injury (DAI) is a brain injury in which scattered lesions occur over a widespread area in white matter tracts as well as grey matter. DAI is one of the most common and devastating types of traumatic brain injury and is a major cause ...

. In some circumstances, concussive injury can cause microvascular disruption,

hemorrhage Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, v ...

, or

subdural hematoma A subdural hematoma (SDH) is a type of bleeding in which a collection of blood—usually but not always associated with a traumatic brain injury—gathers between the inner layer of the dura mater and the arachnoid mater of the meninges surround ...

. Closed head injury (coup contrecoup) can damage more than the impact sites on the brain, as axon bundles may be torn or twisted, blood vessels may rupture, and elevated intracranial pressure can distort the walls of the ventricles. Diffuse axonal injury is a key pathology in concussive brain injury. The

visual system The visual system comprises the sensory organ (the eye) and parts of the central nervous system (the retina containing photoreceptor cells, the optic nerve, the optic tract and the visual cortex) which gives organisms the sense of sight (th ...

may be affected. Contrecoup contusions are particularly common in the lower part of the

frontal lobe The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a groove be ...

s and the front part of the

temporal lobe The temporal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The temporal lobe is located beneath the lateral fissure on both cerebral hemispheres of the mammalian brain. The temporal lobe is involved in pro ...

s. Injuries that occur in body parts other than the brain, such as the

lens of the eye The lens, or crystalline lens, is a transparent biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. By changing shape, it functions to change the focal length of the eye so that it ca ...

, the lung, and the skull may also result from concussion.

History

In the 17th century,

Jean Louis Petit Jean-Louis Petit (13 March 1674 – 20 April 1750) was a French surgeon and the inventor of a screw-type tourniquet. He was first enthusiastic about anatomy and received a master's certificate in surgery in Paris in 1700. He became a member of th ...

described contrecoup injuries. In 1766, the French surgeon

Antoine Louis Antoine Louis (; 13 February 1723, Metz – 20 May 1792) was an 18th-century French surgeon and physiologist. He was originally trained in medicine by his father, a sergeant major at a local military hospital. As a young man he moved to Paris, w ...

coordinated a meeting of the '' Académie Royale de Chirurgie'' on contrecoup injuries, at which papers were to be presented, one of which would be chosen to receive the respected prize, the ''Prix de l'Académie Royale de Chirurgie''. The presenter of the chosen paper was not awarded the prize because he failed to make recommended changes. In 1768, the group met again on the topic, and Louis Sebastian Saucerotte won the prize for his paper describing contrecoup injuries in humans and experiments on animals and recommending treatments such as

bloodletting Bloodletting (or blood-letting) is the withdrawal of blood from a patient to prevent or cure illness and disease. Bloodletting, whether by a physician or by leeches, was based on an ancient system of medicine in which blood and other bodily flu ...

and application of herbs to patients' heads.

In popular culture

* In the Perry Mason TV series, contrecoup lacerations were used as evidence in at least two episodes, including "The Case of the Jaded Joker" (1959) and "The Case of the Bluffing Blast" (1963).Archive of "The Next Big Thing" radio, Jan. 13, 2005
Perry Mason clip played at 23:43 and 28:25. * In " Hawkeye", an episode of ''

M*A*S*H ''M*A*S*H'' (Mobile Army Surgical Hospital) is an American media franchise consisting of a series of novels, a film, several television series, plays, and other properties, and based on the semi-autobiographical fiction of Richard Hooker. Th ...

'', Captain

Hawkeye Pierce This is a list of characters from the ''M*A*S*H'' franchise, covering the various fictional characters appearing in the novel '' MASH: A Novel About Three Army Doctors'' and its sequels, the 1970 film adaptation of the novel, and the televisio ...

, M.D. diagnoses himself as having a contrecoup injury. * In " Meld", an episode of '' Star Trek: Voyager'', the ship's

doctor Doctor or The Doctor may refer to: Personal titles * Doctor (title), the holder of an accredited academic degree * A medical practitioner, including: ** Physician ** Surgeon ** Dentist ** Veterinary physician ** Optometrist *Other roles ** ...

is able to use the distinction between coup injury and contrecoup injury to determine that a dead crewman was murdered. * "Contrecoup" is the title of a

They Might Be Giants They Might Be Giants (often abbreviated as TMBG) is an American alternative rock band formed in 1982 by John Flansburgh and John Linnell. During TMBG's early years, Flansburgh and Linnell frequently performed as a duo, often accompanied by a ...

song off their 2007 album ''

The Else ''The Else'' is the twelfth studio album by rock group They Might Be Giants, released by Idlewild Records in 2007. The album was produced in part by The Dust Brothers, along with Pat Dillett and the band. ''The Else'' was first available for ...

''. It was written as a challenge to create a song using the words "contrecoup", " craniosophic", and "limerent", and likens an infatuation to the effects of a traumatic brain injury. * In Stephen King's novel Duma Key, the main character has brain damage from a contrecoup injury (spelled "contracoup"). *The distinction between coup and contrecoup injuries is described and portrayed in "Betrayal - Part 2", episode 202 of the BBC television drama series " Silent Witness" (2019).

References

External links

* {{wiktionary-inline, contrecoup Neurotrauma