Concussion is the most common type of traumatic brain injury. Unfortunately, many individuals that sustain a concussion are not seen in a medical setting. All health care providers should receive training in identifying the signs and symptoms of concussion in order to provide proper guidance and referral for specialized treatment.
A traumatic brain injury (TBI) occurs when brain function is altered due to an external impact to the head or body, or from inertial forces such as rapid acceleration-deceleration of the brain within the skull.1 National data show that approximately 3-4 million new cases of TBI occur each year in the United States, and concussion accounts for as many as 75% to 90% of all TBIs.2,3 Recent studies report that concussions in youth and adolescents are on the rise, particularly in 10 to 19 year olds, as well as in older adults over the age of 65.4,5 Falls are the primary cause of concussion in elderly adults, while youth sustain concussions due to sports and recreational-related injury.6,7
About 25% of all concussions occur on the job in working age adults, primarily in the manufacturing, construction, and transportation industries.8 A significant percentage of individuals that sustain a concussion are not evaluated in the emergency department, but are either seen in physicians’ offices or out-patient settings. Bryan et al suggest as many as half (53%) of all youth that sustain a concussion due to sports or recreational activities are not evaluated in a medical setting.7 Many individuals with nonsports-related concussion do not seek treatment initially. Some may delay seeking medical care for weeks or months until attempts to self-manage symptoms fail; they are encouraged by family, coworkers, etc, to seek care; or their symptoms become problematic.9 Therefore, practitioners in all health care settings should receive training in concussion diagnosis and treatment.
In 2016, a National Concussion Awareness Day was established to create an opportunity for health care providers, coaches, employers, and the public to discuss signs, symptoms, treatment approaches, and long-term consequences of concussion. Since 2016, yearly bipartisan resolutions from Congress have been adopted to recognize one day in late September as National Concussion Awareness Day to increase public education regarding the epidemic of concussion in the United States.
A conceptual definition of sport-related concussion was recently proposed by the Concussion in Sports Group and published in the 2022 Consensus Statement on Concussion in Sport.10 Sports related concussion was defined as,
“…a traumatic brain injury caused by a direct blow to the head, neck or body resulting in an impulsive force being transmitted to the brain. This initiates a neurotransmitter and metabolic cascade, with possible axonal injury, blood flow change and inflammation affecting the brain. Symptoms and signs may be present immediately, or evolve over minutes or hours, and commonly resolve within days, buy may be prolonged. No abnormality is seen on standard structural imaging studies. Sport-related concussion results in a range of clinical symptoms and signs that may or may not involve the loss of consciousness.”
The physiological processes that take place within the brain as described also occur in nonsports related concussion.
Symptoms and Red Flags
A concussion can result in multiple changes in a number of domains, including physical/somatic, cognitive, emotional, and behavioral.11 Physical or somatic complaints following can include: headache, nausea, dizziness/balance disturbance, fatigue, poor sleep, noise or light sensitivity, blurred vision, hearing impairment, and numbness/tingling. Frequently reported cognitive complaints include: decreased attention/concentration, poor memory, slow information processing speed, difficulty multi-tasking, impaired judgment, impulsivity, and subtle language difficulties (such as word-finding problems). Emotional and behavioral consequences of concussion can include: anxiety, depression, irritability and agitation, increased emotional lability, apathy, and in some instances, aggression.
Most symptoms associated with concussion resolve in a relatively short period of time (ie, 2 to 4 weeks); however, about 10% to 15% of individuals experience symptoms beyond 4 weeks. When symptoms persist beyond 4 weeks, a diagnosis of persistent postconcussive symptoms (PPCS) is offered.9
Diagnosis is complicated because usual imaging techniques (ie, CT scans, MRI) do not readily detect microscopic changes in the brain, and there is considerable symptom overlap between concussion other conditions such as anxiety, depression, and posttraumatic stress disorder.9,11-12
The American College of Rehabilitation Medicine (ACRM) has offered an operational definition and diagnostic criteria for mild TBI/concussion (Table).13
Given that many individuals do not immediately seek treatment after a concussion and the symptom overlap between concussion and other conditions, obtaining a thorough event history is extremely important. During the clinical interview, health care practitioners should query patients regarding any recent falls, vehicular or sporting accidents, or any other event that could have caused a blow to the head or body. A referral for a neuropsychological evaluation can provide information about a patient’s cognitive and psychological functioning, and personality features necessary for differential diagnosis. It can also begin the rehabilitation process by providing education, reassurance, as well as referral for comprehensive therapies to treat cognitive and emotional consequences of concussion, if indicated. While available in research settings but not yet suited for routine use in clinical practice, sophisticated imaging studies and blood biomarkers can detect a concussion. Diffusion tensor imaging (DTI), functional magnetic resonance imaging (fMRI), single photon emission computerized tomography (SPECT) and blood biomarkers, such as glial fibrillary acidic protein (GFAP) and S 100 calcium-binding protein B (S100B) can detect microstructural white matter changes, alterations in blood flow, inflammation, and oxidative stress that accompany concussion.14-16
Research indicates that effective management of concussion includes early identification and treatment.17,18 After a brief, initial period of rest to lessen symptoms and reduce metabolic demands, patients should be encouraged to begin treatment. For most individuals with a concussion, treatment should be symptom-focused and include education about the injury, provide optimistic expectations about recovery and outcome, provide information about how to manage symptoms (ie, headache, sleep disorder, etc), and cautionary statements about returning to activities that involve risk of repeat head injury. Normal physical and cognitive activities can resume slowly while monitoring to ensue symptoms do not worsen.
For individuals with PPCS, a multidisciplinary approach may be indicated. The core multidisciplinary team may include physician specialties (physiatry, psychiatry, neurology, etc), occupational therapy (to improve activities of daily living and monitor timing for return to work and driving), physical therapy (to managing pain, balance problems, vestibular issues), speech/language pathology (for treatment of cognitive-linguistic deficits), counseling (for mood disturbance, sleep disorders, etc), and case management to coordinate treatment.
Dr Seale is the regional director of clinical services at the Centre for Neuro Skills, which operates post-acute brain injury rehabilitation programs in California and Texas. He is licensed in Texas as a chemical dependency counselor and psychological associate with independent practice. He also holds a clinical appointment at the University of Texas Medical Branch (UTMB) in Galveston in the Department of Rehabilitation Sciences.
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