Medical Conditions Related to Brain Injury
Sports Concussions
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Traumatic brain injuries are a common occurrence in sports. Epidemiological studies suggest that over 60,000 traumatic brain injuries occur among high school athletes each year. Football, ice hockey, and soccer are associated with the highest rate of injury. The incidence of traumatic brain injury is even higher when recreational sports such as horseback riding and downhill skiing are considered.
Although athletes occasionally sustain severe brain injuries that can result in fatalities, they are much more likely to sustain milder injuries, typically referred to as concussions. The definition of concussion is still debated, but is commonly said to involve a traumatically induced alteration in mental status that may or may not involve a loss of consciousness. Traditional parameters of concussion involve a loss of consciousness of no longer than 30 minutes, a Glasgow Coma Scale score no less than 13, and post-traumatic amnesia lasting no longer than 24 hours.
Outcomes of Sports-Related Concussion
Sports-related concussions are typically associated with demonstrable cognitive impairment and associated physical symptoms (e.g., headache, fatigue, dizziness) that tend to resolve for most athletes by about 10 days post-injury. Some research suggests that repeated concussions may have a cumulative effect on cognitive functioning.
In some cases, concussions are followed by persistent complaints of physical, cognitive, affective, and behavioral symptoms, sometimes referred to as post-concussion syndrome. Controversy persists regarding the cause of persistent post-concussive symptoms, and whether they arise from primarily physiological or psychological causes.
In rare cases, when repeated concussions or head injuries occur over a brief interval, before recovery can occur from the initial injury, athletes may suffer from second impact syndrome. Second impact syndrome is characterized by the rapid onset of catastrophic cerebral edema and brain swelling that can be life threatening and requires emergency medical treatment.
Evaluation and Management
Concussions are typically managed according to their severity. Table 1 summarizes some of the more common schemes for grading concussions. The guidelines generally distinguish between concussions based on whether there is an accompanying loss of consciousness and on the presence of other symptoms, such as mental confusion and post-traumatic amnesia.
The main objectives of the acute medical evaluation of concussion are to assess vital signs, determine the level of consciousness, and rule out any associated injuries, such as those to the cervical spine. As Table 2 shows, recent guidelines for the management of first concussions in sports recommend evaluation by a hospital emergency department whenever there is any loss of consciousness. The evaluation typically involves careful assessment of neurological status and observation to rule out any evolving neuropathology. Neuroimaging is not indicated in all cases, but is used selectively based on clinical considerations.
In cases of less severe concussion, athletes are typically evaluated on site rather than in hospital emergency departments. The Standardized Assessment of Concussion (SAC) is a brief mental status and neurological screening tool that was developed to provide a standardized and valid method of evaluating athletes within minutes of a concussion. The SAC can be helpful in determining how whether an athlete meets the criteria for return to play set forth in recent guidelines, as shown in Table 2.
The American Academy of Pediatrics and the American Academy of Family Physicians published guidelines for the management of minor closed head injury in children. The guidelines encompass some but not all sports-related concussions, because they were meant to apply only to children or adolescents who have normal mental status on presentation, no abnormal findings on neurological examination, and at most a very brief loss of consciousness (i.e., < 1 minute).
Neuropsychological Assessment
Neuropsychological assessment is widely regarded as the most sensitive method of detecting disturbances in brain function associated with concussion. However, the traditional comprehensive approach to neuropsychological assessment that involves hours of testing is not practical when applied to large groups of athletes. Instead, brief, focused test batteries are needed that can be administered systematically both before and after an injury.
The National Football League and the National Hockey League have both instituted systematic programs of neuropsychological testing. Athletes are administered a brief, standardized test battery during the preseason to establish baseline levels of performance. The tests, which are sensitive to attention, memory, and speed of information processing, are re-administered to athletes who sustain concussions, typically within 48 hours of the injury and at regular intervals thereafter. Recovery to baseline levels of performance is typically required before athletes are allowed to return to play. Similar cooperative programs could be instituted for organized athletic programs at the high school level.
In the absence of programmatic testing, athletes who complain of persistent post-concussive symptoms should be referred for a comprehensive neuropsychological evaluation, which combines a detailed history, structured behavioral observations, and battery of standardized tests. The goals are to document cognitive and behavioral outcomes, draw inferences regarding the integrity of brain function, and generate recommendations for clinical management. Functional neuroimaging techniques, such as Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET), also may have some potential value in the evaluation of athletes with persistent post-concussive symptoms, although additional scientific validation of their sensitivity and specificity is needed.
Prevention and Rehabilitation
Changes in the rules governing athletic competition have reduced the number of sports-related head injuries. For instance, the National Collegiate Athletic Association made the use of the head when tackling illegal in 1976, and the annual incidence of head and neck injuries in football subsequently declined by about 50%. The required use of helmets in many contact sports and advances in helmet design also has resulted in fewer head injuries. Improved conditioning of athletes, especially strengthening of neck muscles, may also help to prevent concussions.
After a concussion occurs, proper discharge instructions to athletes and their families may help to insure appropriate follow-up, and also reduce the likelihood of persistent post-concussive symptoms. Discharge instructions should include a written description of symptoms indicative of worsening brain injury and common post-concussive symptoms, as well as guidelines for return to play and medical follow-up.
A small percentage of athletes who sustain concussions will experience persistent difficulties that may include a variety of physical, cognitive, affective, and behavioral symptoms. An effective treatment plan for managing persistent post-concussive symptoms will often combine education, cognitive rehabilitation, psychological support, and in some cases psychotropic medication.
Keith Owen Yeates, Ph.D., is Director of Pediatric Neuropsychology and Associate Director of the Center for Injury Research and Policy at Children’s Hospital in Columbus, Ohio. He also is Associate Professor in the Department of Pediatrics at The Ohio State University College of Medicine and Public Health. Dr. Yeates is actively involved in grant-funded research focusing on the neurobehavioral outcomes associated with traumatic brain injury, and recently received a 5-year grant from the National Institutes of Health for a longitudinal, prospective study of post-concussive symptoms in children with mild head injuries.
Concussions in Sports by Keith Yeates, PhD, Pediatric Directions magazine; reprinted by permission of Columbus Children’s Hospital, Inc., with all rights reserved. No other use is authorized without the express written permission of Columbus Children’s Hospital.
References
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Poirier, M. P., & Wadsworth, M. R. (2000). Sports-related concussions. Pediatric Emergency Care, 16, 278-283.
Wojtys, E. M., Hovda, D., Landry, G., Boland, A., Lovell, M., McCrea, M., & Minkoff, J. (1999). Concussion in sports. American Journal of Sports Medicine, 27, 676-687.