collegiate sports have yet to validate the claim that mouth guards cut down on concussions; although a study conducted by the nhl showed that symptom severity had significantly decreased with the use of mouth guards. cerebral contusions epidemiology cerebral contusions are bruises to the brain caused by a direct blow to the head causing the brain to bounce against the inside of the skull and bruise brain tissue. the force of the blow causes either a tearing or twisting of the structure and blood vessels which hinders the ability of the receptors to send feedback to the brain. with the tearing or twisting of structure, the brain begins to swell and bleed. since the brain cavity has no room to expand due to the swelling, bruises begin to form. due to the nature of the injury, most of the contusive damage is found deeper in the brain. in sports, most cerebral contusions are caused when the brain is either suddenly accelerated, decelerated, or strikes an immovable object. when the blow happens, brain tissue can be damaged, sometimes resulting in the need for hospitalization and surgery. a resection of the contused tissue is needed within surgery pending the severity of the incident. the highest rates of contusions occur in men between the ages of 15 to 24, somewhat due to their aggressive nature. if a person sustains a contusion one time, they are more likely to sustain a repeated one. (see cerebral contusion for more information) signs and symptoms in sports in the heat of a game, it may be hard to see or feel symptoms relating to cerebral contusions. if any of these signs are visible or as an athlete, you feel them, remove yourself from competition immediately. cerebral contusions and other injuries can occur in any sport, not just in the traditional "collision" sports. the most popular sport to cause cerebral contusions is american football due to the drastic acceleration/deceleration of the brain. immediate signs of a cerebral contusion headache nausea slurred speech restlessness pupil dilation memory loss personality shift seizures post-game symptoms loss of consciousness severe headaches coma (due to loss of consciousness) if any of these symptoms are felt or noticed, a hospital visit is needed where further machine testing is done. in boxing, the rapid deceleration of the brain after an impact causes the symptoms to progress much faster or at a more traumatic rate. doctors ringside monitor a boxer's attitude and brain function throughout the fight and are able to stop the match following startling news. diagnosis in sports contusions are identified with two forms of diagnosis: acceleration of the brain and direct trauma. a direct trauma injury is much more severe than an acceleration injury (in most cases) and requires much more intensive diagnosis and testing. the full extent of the injury may not be known until testing done in a hospital is complete. in football, medical trainers are well versed to diagnose symptoms pertaining to a traumatic brain injury. they are not, however, able to determine what type of injury it is or the extent the injury stems. football trainers can medically clear or not clear players based on brain injury symptoms. if a trainer feels that certain symptoms exist that are similar to that of cerebral contusions, they will take the player out of the game and rush them to the hospital. upon admission into the hospital, a ct scan will be ordered. a ct scan is the quickest method to diagnose cerebral contusions because it can be performed immediately and have fairly exact findings. the best method, as suggested by medical doctors, is an mri because they present more sensitive and accurate findings. mri's, however, must be scheduled and cannot be completed immediately following the injury. mri's also take a long time to perform where the injury a player sustained may get worse within that time frame. case study example history: the individual is possibly unconscious when examined by medical personnel on the field. a common symptom is prolonged unconsciousness (coma), however this player reports headache, dizziness, nausea, vomiting, and weakness of the extremities (paresis) and makes inappropriate responses to questions. physical exam: the individual's level of consciousness is disturbed. a neurological examination may not reveal any localizing signs. the individual with no other serious injuries than cerebral contusion will not have a fractured skull or any signs of opening or penetration of the skull. tests: skull x-rays check for a fracture. ct or mri detect any bleeding in the skull. the glasgow coma scale classifies the severity of brain injury, with a score of 15 as normal and progressively lower scores indicating greater neurologic injury to the brain. after testing is completed, doctors will make an estimate on the extent of the injury and possible recovery time. if cranial bleeding and swelling is minor, a short hospital stay (up to a week) is needed with close observation. if bleeding is severe, the player may be treated as a patient with a severe head injury (with surgery as the main option). this process requires the patient to be admitted into an intinsive care unity with close monitoring of blood levels and brain activity. prognosis (short/long-term effects) the effects of a cerebral contusion depend on the cause of the injury and what part of the brain was most affected. outcomes vary from minor injuries that require short recovery times to severe injuries that can lead to death. short-term effects of cerebral contusions can range from a mild headache to feeling lightheaded for a few days. most short-term effects match that of a mild head injury while long-term effects can be much more serious. most long-term injuries require surgery, rehabilitation, and close monitoring. in small cases, cerebral contusions can lead to death (about 15 per 100,000 people). if a cerebral contusion leads to a coma, recovery can be very long and rehabilitation extensive. if the coma is long, the probability of dying or permanent neurological damage is very possible. prevention in sports rules exist within each sport to help prevent cerebral contusions and traumatic brain injuries. however, individual athletes are the best prevention against their own injuries. in a game, athletes notice when they have the symptoms of a cerebral contusion and should take themselves out of the game. it may be hard for medical personnel or coaches to notice when a player has a traumatic brain injury, so it is in the player's best interest to be removed from play. in hockey, traumatic brain injuries constitute 10%-15% of all head injuries. with the high percent of injuries being traumatic, extensive design improvements have been made to helmets. these improvements reduce the risk of cerebral contusions by providing more padding around the skull and a chin strap that keeps the helmet snug. in baseball, major improvements to helmets have been made to protect batters from the impact a baseball can have when hitting their head. helmets, before this major improvement, were designed to withstand a velocity of 70 mph from a pitch or foul ball. since the company rawlings' new design, helmets can withstand a velocity of 100 mph and have further padding around the softer parts on the side of the skull. american football players have sued the national football league (nfl) for $1 billion for misrepresenting the long-term health impacts associated with on-field head injuries. however, even if a sports organization has an accurate understanding of the value of injury prevention techniques, the management team (such as coaching staff and medical staff) may fail to communicate this knowledge effectively to elite athletes. previous studies argued that there is no one-size-fits-all program contributing to better knowledge or understanding of injury consequences to elite athletes. dementia pugilistica (punch-drunk syndrome) epidemiology a syndrome affecting boxers that is caused by cumulative cerebral injuries and is characterized by impaired cognitive processes (as thinking and remembering), parkinsonism, impaired and often slurred speech, and slow poorly coordinated movements especially of the legs. dementia pugilistica, more commonly known as "punch drunk syndrome", is a degenerative brain disorder resulting from head trauma. dementia pugilistica (dp) is typically associated with the sport of boxing; although symptoms of dp may appear immediately after a single traumatic brain injury, they are typically described following the cessation of exposure to chronic brain injury. signs and symptoms in sports some of the subjective symptoms experienced after a knockout are headaches, tinnitus, forgetfulness, impaired hearing, dizziness, nausea and impaired gait. approximately ten percent of these active boxers reported constantly experiencing forgetfulness, headaches and other symptoms. symptoms can be progressive and can develop late into a boxer's career or possibly years into retirement. some of the earlier symptoms of "punch drunk syndrome" are noticeable in extremities; such as trembling hands or feet, or an instability in equilibrium. signs of chronic brain damage can also affect irritability, paranoia and cause violent outbursts. diagnosis in sports dementia pugilistica is difficult to diagnose until the later stages of a boxer's life. symptoms are not apparent until boxer's are years into retirement. the damage is done in four primary sites of the brain: the septal regions, the cerebellum, the substantia nigra and the neurons. the septa end up separated and torn apart while the ventricles become enlarged. "the main motor pathways in the cerebellum and substantia nigra are affected, as well as the foramen magnum." lastly, the neurons in the brains of boxer's have a "bizarre tendency for many neurons, mainly in the deep temporal grey matter, to develop abnormal neurofibrils called alzheimer tangle. the most successful way to diagnose dp is through magnetic resonance imaging techniques, more commonly known as an mri. segmented inversion recovery ratio imaging technique is based on the ratio of a white matter suppressed image and gray matter suppressed image. "the (sirrim) technique improves the differentiation of gray matter from white matter and is sensitive to detect abnormalities of intracellular space, including changes during cellular death." prognosis (short/long-term effects) multiple studies have concluded that there is neurological evidence of damage to pyramidal, extrapyramidal and cerebellar systems with associated psychosis, memory loss or dementia, personality change and social instability. after fighting, boxers show raised cerebrospinal fluid levels of neurofilament light chain and total tau then they did after three months with no boxing. prevention in sports protective measures have been taken especially in amateur boxing, such as the wearing of a head guard, more heavily cushioned gloves (weighing 10 ounces in amateur boxing and 8 ounces in professional boxing), shorter and fewer rounds, the addition of the 'outclassed rule' (where the point difference becomes greater than 20), and the option for the boxer to interrupt the fight itself. hematoma epidemiology a hematoma is a localized collection of blood that gathers outside the blood vessels in an area it does not belong. specifically a hematoma is tissue damage due to acceleration or deceleration from unrestricted movement, in which the result is shearing of the brain tissue. two types of hematomas occurring within the brain are: subdural and extradural hematomas, which are classified as a traumatic brain injury (tbi). when a direct blow to the head occurs, there is bruising to the brain and damage to the internal tissue and blood vessels. additionally, the jarring of the brain against the skull causes hematomas. injuries commonly occur during contact sport such as boxing, football, basketball, motor cycling, scuba diving, mountaineering, hang gliding, skydiving, and horseback riding. council on scientific affairs. following a serve brain injury or a skull fracture one of the two hematomas may occur. an extradural hematoma is a tbi where blood collects between the inside of the skull and the dura, the thick outer covering of the brain. a subdural hematoma is a localized collection of blood under the surface of the dura matter. blood collects on the outermost layer of the brain and creates an intracranial pressure. signs and symptoms in sports generally, symptoms for hematomas are confused speech, difficulty with balance or walking, headaches, lethargy or confusion, nausea or vomiting, numbness, seizures, slurred speech, visual disturbances, and weakness. for example, an athlete who experiences a subdural hematoma will experience loss of consciousness with little or no lucidity. pupils are often dilated or unequal. additionally, hemiparesis, seizure activity, and vomiting, may be apparent. an epidural hematoma typically results in serve a headache which is