Basics
Description
- Concussion is a complex pathophysiologic process affecting the brain, induced by traumatic biomechanical forces.
- There is a graded set of clinical symptoms that define concussion, which may or may not involve a loss of consciousness.
- Concussion may be caused either by a direct blow to the head or a blow to the face, neck, or elsewhere on the body with an "impulsive"Ě force transmitted to the head.
- Concussion typically results in the rapid onset of short-lived impairment of neurologic function that resolves spontaneously. In a small percentage of children, postconcussive symptoms may be prolonged.
- Concussion may result in pathologic changes, but the acute clinical symptoms largely reflect a functional rather than structural injury and no abnormality is seen on standard neuroimaging studies.
Epidemiology
- A recent review estimated that up to 3.8 million recreation- and sport-related concussions occur annually in the United States.
- Concussion is underreported.
- Most common sports include football, ice hockey, soccer, wrestling, lacrosse, basketball, baseball, softball, field hockey, and volleyball.
- Although concussion is overall more common in boys, girls have higher rates of concussion than boys in similar sports.
- Risk of injury depends on game, position, prior concussion, and use of helmet.
General Prevention
- Nothing has been shown to prevent concussion.
- Helmet use is essential at reducing the severity of a blow to the head.
- Given that children may have a sense of invulnerability and desire to return to usual activities quickly, preparticipation medical visits should emphasize that reporting concussion immediately is essential and that loss of consciousness is not the only manifestation of concussion.
Pathophysiology
- The brain is buoyed in the cranium by cerebrospinal fluid that acts as protective insulation. With acceleration-deceleration, the brain continues to experience momentum and strikes against bone. The temporal and frontal lobes are particularly prone to injury because of their location adjacent to irregular parts of the skull.
- Depressed level of consciousness is thought to be the result of rotational stretch injury to the reticular activating system in the dorsal aspect of the brainstem.
- Pathologic changes after concussion include alterations in neuronal depolarization and neurotransmitter release, impaired axonal function, decreased cerebral blood flow, and altered brain autoregulation and glucose metabolism.
- Children may respond to brain trauma differently than adults due to developmental factors such as brain size, brain water content, myelination level, skull and suture geometry and elasticity, and differential skull to body proportions.
Diagnosis
History
- Detailed history of traumatic event
- Detailed symptom evaluation
- History of prior concussions, including surrounding circumstances
- History of preexisting cognitive or attention problems should be elicited to help guide interpretation of postinjury testing.
Signs and Symptoms
- Standardized, validated instruments for mental status testing are available and can be administered quickly on the sideline (i.e., Sport Concussion Assessment Tool 2 [SCAT-2])
- Postconcussive symptoms may be divided into 4 domains:
- Somatic: headaches, fatigue, decreased energy, nausea, vision change, tinnitus, dizziness, incoordination, and balance difficulty
- Emotional/behavioral: irritability, increased emotionality, personality change, depression, or anxiety
- Cognitive: slowed thinking and response time; impaired concentration, learning, and/or memory; and reduced problem-solving ability
- Sleep disturbances are common.
Physical Exam
- Onsite and acute evaluation should include the usual ABCs and evaluation for potential associated injuries such as cervical spinal injury.
- A detailed neurologic examination should be performed to detect focal signs suggestive of serious neurologic impairment and to allow accurate observation over time.
- Mental status: orientation (person, place, time), concentration (digit span), and memory (anterograde and retrograde)
- Cranial nerves: pupil reactivity, eye movements (particularly smooth pursuit and saccadic movements), visual fields, face movement and sensation, tongue protrusion
- Motor: strength and tone
- Sensory: gross sensory deficits
- Cerebellar: agility, finger-to-nose-to-finger, rapid alternating movements (finger tapping, toe tapping), tandem gait (forward and backward, eyes open and closed)
- Exertion provocative tests: 5 push-ups, 5 sit-ups, 5 knee bends, 40-yard sprint; look for change in symptoms/exam.
Diagnostic Tests & Interpretation
Imaging
- Structural lesions are absent on standard CT and MRI in concussion.
- Computed tomography of the head (HCT) is the test of choice in the acute evaluation of suspected intracranial hemorrhage or skull fracture in head trauma.
- Decision rules exist to determine those children at low risk for clinically important brain injury who may not need an HCT.
- There is increased suspicion of intracranial injury in patients with abnormal mental status, non-frontal scalp hematoma, prolonged loss of consciousness, severe injury mechanism, palpable skull fracture, vomiting, and severe headache.
- MRI is the imaging modality of choice in the subacute or chronic evaluation of concussion
Diagnostic Procedures/Other
- Neuropsychological testing: Computerized testing is now widely available and baseline testing is being performed by many school athletic departments. Research is still needed regarding the optimum timing of this testing and whether it improves outcome.
Treatment
General Measures
- Remove the child from the activity with no return to play if concussion is suspected.
- Monitor the athlete for several hours after the injury to evaluate for any deterioration.
- Consider referral to the emergency department if there is repeated vomiting, severe or worsening headache, seizure, unsteady gait, slurred speech, weakness or numbness in the extremities, unusual behavior, signs of a basilar skull fracture, or a GCS <15.
- There is currently no evidence-based research on the use of any medication in the treatment of the concussed pediatric athlete.
Issues for Referral
- Neuropsychological evaluation should be considered in children with multiple concussions or when recovery is not progressing as expected. This evaluation can document impairment, identify factors contributing to persisting difficulties, and guide school accommodations or formal intervention.
- If admitted for observation, consults by speech therapy, physical therapy, and psychiatry should be considered to evaluate for subtle sequelae.
Surgery/Other Procedures
Neurosurgical evaluation or transfer to a trauma center should be considered for symptoms of prolonged unconsciousness, persistent mental status alterations, worsening postconcussive symptoms, abnormalities on neurologic examination, or abnormalities on neuroimaging. †
Inpatient Considerations
Admission Criteria
Consider admission if the child continues to have altered level of consciousness, if focal neurologic signs are present, or if patient remains severely symptomatic. †
Nursing
If observation is required, nursing staff must be able to perform neurologic assessments at regular intervals. †
Discharge Criteria
- Planning must be individualized depending on severity of symptoms, family support, and presence of associated injuries.
- The child and guardian should receive return to play guidelines focused on avoiding repeat concussions as concussions have a cumulative effect and result in increased vulnerability to future injuries.
- No athlete should return to play while still symptomatic from a concussion. This includes physical, cognitive, or behavioral symptoms. There must be no symptoms or signs at rest or during exertion.
- Activities with a high cognitive demand should be limited while symptomatic, including television, computer, videogames, and texting. School accommodations may be needed.
- Before considering return to play, any medication to reduce symptoms must be stopped and the athlete must be symptom-free off medications.
- Return to play should occur in a gradual fashion while monitoring for symptoms because symptoms may be aggravated with exertion. Consider in sequence light aerobic activity, noncontact sport-related activity, full practice, and then game play.
- Retirement should be considered for any athlete who has sustained 3 concussions in an individual season or has had postconcussive symptoms for more than 3 months, when recovery requires an increasing amount of time, or when concussions occur with less forceful injury.
Ongoing Care
Follow-up Recommendations
Patient Monitoring
If the patient is discharged home for observation, the guardian should have detailed instruction regarding reasons to return to the ED. These include difficulty awakening or staying awake, worsening headache or dizziness, emesis, seizures, blood or clear fluid from the ears or nose, major changes in behavior, or any focal weakness/sensory/vision changes. †
Prognosis
- In general, the prognosis is excellent but depends on the severity of the injury.
- The typical adult patient with a concussion will recover to baseline function in 6-12 weeks.
- Athletes and children usually recover in 48 hours. However, children with previous head injury, learning difficulties, or neurologic, psychiatric, or family problems may continue to show significant ongoing problems at 3 months.
- Chronic headaches, persistent difficulty with short- and long-term memory, and episodic confusion are common sequelae of the cumulative damage that occurs with repeated concussive injuries.
Complications
- Postconcussion symptoms such as confusion; altered concentration, memory, and problem solving; irritability; emotional changes; and headaches may take several months to resolve.
- Serious head injury may occur and requires immediate neurosurgical evaluation and neurocritical care. Serial HCT imaging may be necessary as intracranial lesions, such as contusion or hemorrhages (epidural, subdural, intraparenchymal), can expand. These may occur with or without skull fracture and may occur without an initial loss of consciousness.
Additional Reading
- Centers for Disease Control and Prevention. Nonfatal traumatic brain injuries related to sports and recreation activities among persons aged ‚ȧ19 years-United States, 2001-2009. MMWR Morb Mortal Wkly Rep. 2011;60(39):1337-1342. †[View Abstract]
- Giza †CC, Kutcher †JS, Ashwal †S, et al. Summary of evidence-based guideline update: evaluation and management of concussion in sports: report of the Guideline Development Subcommittee of the American Academy of Neurology. Neurology. 2013;80(24):2250-2257. †[View Abstract]
- Halstead †ME, Walter KD; The Council on Sports Medicine and †Fitness. Clinical report-sport-related concussion in children and adolescents. Pediatrics. 2010;126(3):597-615. †[View Abstract]
- Kuppermann †N, Holmes †JF, Dayan †PS, et al; Pediatric Emergency Care Applied Research †Network. Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet. 2009;374(9696):1160-1170. †[View Abstract]
- McCrory †P, Meeuwisse †W, Johnston †K, et al. Consensus statement on concussion in Sport 3rd International Conference on Concussion in Sport held in Zurich, November 2008. Clin J Sports Med. 2009;19(3):185-200. †[View Abstract]
- U.S. Department of Health and Human Services. Centers for Disease Control and Prevention. Heads Up toolkits. Atlanta, GA: Centers for Disease Control and Prevention; 2005.
Codes
ICD09
- 850.9 Concussion, unspecified
- 310.2 Postconcussion syndrome
- 780.93 Memory loss
- 850 Concussion with no loss of consciousness
- 850.12 Concussion, with loss of consciousness from 31 to 59 minutes
- 850.2 Concussion with moderate loss of consciousness
- 850.5 Concussion with loss of consciousness of unspecified duration
- 850.3 Concussion with prolonged loss of consciousness and return to pre-existing conscious level
- 850.4 Concussion with prolonged loss of consciousness, without return to pre-existing conscious level
ICD10
- S06.0X0A Concussion without loss of consciousness, initial encounter
- F07.81 Postconcussional syndrome
- R41.3 Other amnesia
- S06.0X9A Concussion w loss of consciousness of unsp duration, init
- S06.0X7A Concussion w LOC w death due to brain injury bf consc, init
- S06.0X5A Concussion w LOC >24 hr w ret consc lev, init
- S06.0X1A Concussion w LOC of 30 minutes or less, init
- S06.0X3A Concussion w loss of consciousness of 1-5 hrs 59 min, init
- S06.0X8A Concussion w LOC w death due to oth cause bf consc, init
- S06.0X6A Concussion w LOC >24 hr w/o ret consc w surv, init
- S06.0X4A Concussion w LOC of 6 hours to 24 hours, init
- S06.0X2A Concussion w loss of consciousness of 31-59 min, init
SNOMED
- 81371004 Concussion (disorder)
- 40425004 postconcussion syndrome (disorder)
- 275277000 post-traumatic amnesia (finding)
- 62106007 concussion with no loss of consciousness (disorder)
- 110030002 Concussion injury of brain (disorder)
- 62564004 concussion with loss of consciousness (disorder)