Ryan Petering and Robert Cloutier
It is estimated that 3.8 million concussion injuries occur in the United States annually, though many of these go unreported and medical care is not sought (1). Between 2001 and 2009 an average of 173,285 persons aged 19 years or younger presented to emergency departments (EDs) annually for nonfatal traumatic brain injuries (TBIs) related to sports and recreational activities (2). Annual TBI ED visit rates increased 62% during this period. American football, playground activities, basketball, and soccer have the greatest number of TBI-related ED presentations (2). The most common ages for sports-related concussion ED presentation are 14 to 18 years. Males (77%) present more frequently than females (3). However, it appears that in sports with similar rules (e.g., soccer) females have a higher number of concussions and report increased severity compared with males (4). The majority of patients with sports-related concussion (95%) are discharged home following ED evaluation (3).
This chapter discusses concussion specifically in the setting of a sports-related event. See also Chapters 246 and 247.
CLINICAL PRESENTATION
Concussion, mild TBI, and TBI refer to similar events. TBI includes all head injuries and often refers to more serious and life-threatening presentations. Mild TBI typically refers to an injury to the head, with or without loss of consciousness, and a Glasgow Coma Scale (GCS) of 13 to 15 (5). Concussion is defined as a traumatically induced transient disturbance of brain function (4,6). It is important to note that while concussion most often occurs following a direct blow to the head, other mechanisms such as whiplash may transmit force to the head and cause concussion as well. Symptoms are typically immediate and consist largely of functional disturbances; associated structural abnormalities on imaging studies are rare (7).
Consensus concussion panels have recommended avoiding previously associated adjectives such as “mild,” “moderate,” or “severe,” as these terms have little to no prognostic value for individual patients. Unfortunately, concussions judged as “mild” may cause persistent symptoms that can last for months to years.
The symptoms of concussion are diverse and variable. It is helpful to think of symptoms in the categories of (1) physical, (2) cognitive, (3) emotional, and (4) sleep-related. Physical symptoms include headache, nausea, vomiting, balance problems, dizziness, visual problems, fatigue, sensitivity to light and/or noise, or numb or tingling sensations. Loss of consciousness can occur with concussion injuries, but is not required for the diagnosis; only about 10% of concussions are associated with a loss of consciousness (4). Cognitive symptoms include feeling mentally “foggy” or dazed, difficulty concentrating, forgetfulness, confusion about recent events, slowness in responding to questions, and repetitive questioning. Emotional symptoms include irritability, sadness, emotional lability, and nervousness. Sleep changes include drowsiness, sleeping more or less than usual, and difficulty initiating sleep.
DIFFERENTIAL DIAGNOSIS
A comprehensive primary and secondary survey should be performed to identify coexisting injuries. Among the most important to consider are fracture, intracranial hemorrhage, and structural brain damage. The past medical history should identify preexisting medical conditions that may contribute to or complicate a concussion.
ED EVALUATION
Initial ED evaluation should determine whether imaging is required. Clinical evaluation should include a thorough history to determine the specifics of the injury mechanism and the symptoms reported. Physical exam should include a comprehensive neurologic examination.
Skull radiographs are not recommended (5). A level A recommendation is given for noncontrast computed tomography (CT) for patients with loss of consciousness or posttraumatic amnesia if one or more of the following are also present: headache, vomiting, drug or alcohol intoxication, deficits in short-term memory, physical evidence of trauma above the clavicles, posttraumatic seizure, GCS score less than 15, focal neurologic deficit, or coagulopathy. The guideline gives a level B recommendation for noncontrast head CT for patients without loss of consciousness or posttraumatic amnesia if focal neurologic deficit, vomiting, severe headache, physical signs of basilar skull fracture, GCS score less than 15, coagulopathy, or a dangerous mechanism of injury (ejected from motor vehicle, a pedestrian struck, and a fall from a height of more than 3 ft or five stairs) (5).
Up to 15% of patients presenting to the ED following TBI who have a GCS score of 15 are found to have an acute intracranial lesion on head CT (8–13). However, less than 1% of these patients require neurosurgical intervention (9,10,14).
KEY TESTING
• Noncontrast head CT scan MAY BE ordered in patients WITHOUT loss of consciousness OR posttraumatic amnesia with ONE of the following: (1) focal neurologic deficit, (2) vomiting, (3) severe headache, (4) physical signs of a basilar skull fracture, (5) GCS score less than 15, (6) coagulopathy, (7) dangerous mechanism of injury.
• Noncontrast head CT scan SHOULD be ordered for patients WITH loss of consciousness OR posttraumatic amnesia and any of the above criteria or any of the following: (1) drug or alcohol intoxication, (2) physical evidence of trauma above the clavicles, (3) short-term memory deficits, (4) posttraumatic seizure.
ED MANAGEMENT
Headache and nausea or vomiting require symptomatic treatment. It is advisable for concussed patients to be kept in quite, low-light environments to avoid exacerbating their symptoms. Suspected fracture, intracranial bleeding or other injury, or focal neurologic deficits should prompt immediate neurosurgical consultation.
CRITICAL INTERVENTIONS
• Determine the need for imaging to identify fracture or intracranial injury.
• Arrange for close follow-up and inform the patient and caregivers about the natural course of concussive symptoms and the need for full cognitive rest.
DISPOSITION
Patients with isolated concussion may be discharged from the ED since they are at minimal risk for developing an intracranial lesion. However, it is important that discharge instructions note the possibility of worsening symptoms or signs consistent with an intracranial process. Repeated vomiting, worsening headache, loss of consciousness, increasing confusion or agitation, seizure activity, vision changes, weakness or numbness, and difficulty walking are symptoms that warrant further evaluation. The CDC has published downloadable documents ideal for use in the ED discharge setting; these can be found at http://www.cdc.gov/concussion/pdf/TBI_Patient_Instructions-a.pdf.
Consensus treatment guidelines recommend initial mental, physical, and emotional rest. Patients should be advised to rest as much as possible, avoid activities that worsen their symptoms, avoid physical activity, and avoid excessive screen time (television, phones, and electronic devices). Consideration should be given to advising patients to miss school or work as needed while symptoms are present, as often these activities may exacerbate symptoms.
Discharged patients should be advised to follow-up within a week of injury with a provider familiar with the management of concussion. Athletes should be advised not to return to participation in sports until they are cleared by a medical provider. Patients are advised to rest until their symptoms resolve completely without the use of medications. A graded approach to physical activity is then recommended, with activities increased in intensity and duration each day. If symptoms increase during the return to play protocol, patients should return to the previous day’s activity level. Return to play must be guided by symptoms and not by fixed time spans such as “1 week after injury.”
It is estimated that 90% of concussion victims recover within 7 days of their injury (15–17). Concussion symptoms that persist 4 to 6 weeks following the concussive event are characterized as postconcussion syndrome. This syndrome may persist for months to years and can have a profound impact on patients’ lives, school, or work schedules. Risk factors at initial presentation have yet to be identified to predict the risk of developing postconcussive syndrome. These patients should be referred to a concussion rehabilitation team, which typically includes medical providers, physical therapist, speech therapists, and occupational therapists trained specifically in concussion management.
Common Pitfalls
• Failing to diagnose a concussion when a patient has a distracting additional injury (e.g., fracture or other injury).
• Dismissing a concussion as “mild” because there are no severe findings on presentation.
• Recommending that an athlete can return to play at a predetermined amount of time (e.g., 1 week after injury) without undergoing further evaluation on follow-up.
REFERENCES
1. Faul M, Xu L, Wald MM, et al. Traumatic Brain Injury in the United States. Atlanta, GA: Emergency Department Visits, Hospitalizations, and Deaths, Centers for Disease Control and Prevention, National Center for Injury Prevention and Control; 2010.
2. Gilchrist J, Thomas KE, Xu L, et al. Nonfatal traumatic brain injuries related to sports and recreation activities among persons aged ≤19 years—United States, 2001–2009. MMWR. 2011;60(39);1337–1342. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6039a1.htm. Accessed June 20, 2013.
3. Zhao L, Han W, Steiner C. Sports related concussions, AHRQ Statistical Brief #114. 2008. http://www.hcup-us.ahrq.gov/reports/statbriefs/sb114.jsp. Accessed June 23, 2013.
4. Harmon KG, Drezner JA, Gammons M, et al. American Medical Society for Sports Medicine position statement: Concussion in sport. Br J Sports Med. 2013;47:15–26.
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6. www.cdc.gov/concussion. Accessed June 23, 2013.
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