Chapter 11 – Concussion

Chapter 11 Concussion

Melissa D. Leber


  • A concussion is any injury to the head or neck that alters the way the brain functions. It can also be caused by an injury to any part of the body that causes an impulsive force transmitted to the head.1 The mechanical insult leads to a metabolic disturbance that causes the symptoms of concussion.1 It can be from direct trauma to the head, trauma to the neck, or a shaking or sudden severe movement of the head. There does not have to be a loss of consciousness to diagnose concussion.1

  • Symptoms of a concussion can be transient or prolonged. Symptom onset can be minutes to hours to days after the injury.1, 2

  • Diagnostic criteria: An appropriate mechanism of injury followed by any one, or combination of, possible symptoms (see Table 11.1 for complete list): headache, nausea, dizziness, blurred vision, difficulty concentrating, difficulty sleeping, sleeping more than usual, difficulty remembering, or feeling mentally foggy.13

    • Symptoms are caused by neuronal functional abnormalities, rather than structural abnormalities.4

    • There are no gross anatomic lesions, and therefore there are no pathologic findings on brain imaging.4

  • Age: There is no minimum or maximum age at which a patient can sustain a concussion. The younger one is, the more susceptible one is to prolonged damage.4

  • Prognosis: Typically, patients fully recover (symptom free) within seven to ten days of the initial injury.13, 5

    • Risk factors for a longer recovery time include:

      • Progressively longer recovery times after previous concussions.3, 4

      • History of depression, anxiety, or other psychiatric illness. 4

      • History of attention deficit hyperactivity disorder (ADHD) or learning disability.4

      • Personal or family history of headaches or migraines.

  • The more concussions a patient has sustained, the easier it is to sustain a second concussion.1, 3 The brain may be more sensitive to an even more mild impact or trauma because concussed neurons and mitochondria are more vulnerable to further injury.6, 7

  • Post-concussive syndrome: This occurs when symptoms of concussion last for weeks to months to years, or even indefinitely. There is no clear consensus on how long symptoms of concussion must be present prior to making this diagnosis.

Table 11.1 Possible Concussion Symptoms

Headache Nausea Vomiting
Headache Nausea Vomiting
Balance Problems Dizziness Fatigue
Trouble Falling Asleep Sleeping More than Usual Sleeping Less than Usual
Drowsiness Sensitivity to Light Sensitivity to Noise
Irritability Sadness Nervousness
Feeling More Emotional Numbness or Tingling Feeling Slowed Down
Feeling Mentally “Foggy” Difficulty Concentrating Difficulty Remembering
Visual Problems (blurred vision, double vision, etc.)

Anatomical Considerations / Pathophysiology

  • A mechanical insult causes a complex cascade of neurochemical and neurometabolic changes in the brain.6, 8 This results in the following changes:

    • Ion flux of various neurotransmitters and amino acids.

    • Glucose hypometabolism

    • Decreased cerebral blood flow.

    • Influx of calcium ions into mitochondria causes oxidative dysfunction.

    • These changes are usually transient after one concussion but there can be more persistent changes in ion flux after repetitive head injury.6

  • These changes cause swelling of brain cells which takes time to recover. During this recovery time, the cells are more vulnerable to further damage, and may be permanently affected, causing cerebral edema, if the brain is impacted again6, 7. This recovery period typically lasts one to two weeks, and it is during this period, when the cells are more vulnerable to impact, that the patient is susceptible to second impact syndrome (discussed further in the Complications section later).6, 7

Focused History and Physical Exam

  • Initial evaluation of any patient sustaining a head injury should be aimed at ruling out any head injury red flags, which include:

    • Unequal pupils

    • Any focal neurological deficit

    • Extreme drowsiness or unarousable.

    • Worsening headache.

    • Weakness, incoordination

    • Multiple episodes of vomiting.

    • Slurred speech

    • Seizures

    • Confusion or agitation

    • Unusual behavior or observer concern.

  • Once a severe head injury, For example, intracranial hemorrhage, has been ruled out, the patient should be further evaluated for other injuries such as concussion.

  • Concussion specific questions to include in a comprehensive patient history:

    • For emergency physicians present at the event:

      • Sideline Concussion Assessment Tool (SCAT) and Maddocks questions9, 10. To be used at time of injury only:

        • At what venue are we (name of field/stadium/rink)?

        • Who scored last (which team)?

        • What half/period/quarter/ is it currently?

        • What team did we play last?

        • Did we win the last game?

    • Injury-related questions

      • How did the head injury occur (mechanism of injury)?

      • Did you have any physical symptoms associated with the injury? (e.g., unsteady gait, blurry vision)

      • How did you react to the injury? (e.g., stand up immediately, hold head in lap, lie down, collapse)

      • Did you lose consciousness?

      • Do you have amnesia to the event?

      • Did you continue participating in the event/activity?

    • Signs and symptoms (see Table 11.1 for complete list)

      • Which signs/symptoms did you have immediately after the injury?

      • Did any of symptoms develop later on?

        • How long after the injury did they begin?

    • Concussion-related history

      • Have you ever had a concussion in the past?

        • If so, when did it occur?

        • How long did it take you to completely recover?

    • Past medical history (pertinent to concussions)

      • Do you have any history of depression, anxiety, or other psychiatric illness?

      • Do you have any history of ADHD or learning disability?

      • Do you have a personal history or family history of headaches or migraines?

  • Concussion-specific physical exam

    • Head and face exam

      • Is there evidence of a forceful blow to the head?

      • Is there presence of a hematoma?

        • Is it expanding?

      • Is there a scalp laceration or any other head/face trauma?

    • Musculoskeletal exam

      • Evaluate for neck and back ROM

      • Check for midline spinal tenderness.

    • Neurologic exam

      • Orientation – alert and oriented to person, place, time.

      • Cranial nerve exam (II-XII):

        • II – Optic

        • III – Oculomotor

        • IV – Trochlear

        • V – Trigeminal

        • VI – Abducens

        • VII – Facial

        • VIII – Acoustic

        • IX – Glossopharyngeal

        • X – Vagus

        • XI – Spinal Accessory

        • XII – Hypoglossal

      • Cerebellar testing – Finger to nose.

      • Assess for gait abnormality.

      • Balance test – Balance Error Scoring System (BESS).11, 12

        • Have the patient close eyes and put hands on hips. With each maneuver below, count the number of errors (see definitions below) made in 20 seconds. Patient is allowed a maximum of 10 errors per stance below:

          • Double leg stance – feet are together, flat on the floor (Figure 11.1).

          • Tandem stance – stand heel-to-toe with nondominant leg in back (Figure 11.2).

          • Single leg stance – balance on nondominant leg (Figure 11.3).

        • An error is defined as the patient moving the hands off the hips, opening the eyes, taking a step, stumble, or fall, or abduction or flexion of the hips more than 30°.

    • Ophthalmic exam

      • Visual acuity

      • Extraocular motions – test smooth pursuits, horizontal saccades, vertical saccades, and convergence.

    • Cognitive assessment

      • Concentration tests.

        • Spell the word world in reverse (D-L-R-O-W).

        • State the months of the year in reverse order.

          • December, November, October, September, August, July, June, May, April, March, February, January.

        • Repeat numbers in reverse order.

          • 5–7–4

          • 9–6–2–4

          • 3–4–8–8–3

      • Immediate and delayed memory – Give the patient five words to remember. Ask them to repeat the five words immediately and then after a few minutes (three to five) ask them to repeat the same five words. Assess for accuracy.

        • For example, key, carpet, school, banana, ribbon.

Figure 11.1. Proper positioning for BESS Balance Testing – Double Leg Stance: Feet together, side by side.

Figure 11.2. Proper positioning for BESS Balance Testing – Tandem Stance: Heel-to-toe with the patient’s nondominant leg in the back.

Figure 11.3. Proper positioning for BESS Balance Testing – Single Leg Stance: Balance on the nondominant leg.

Differential Diagnosis – Emergent and Common Diagnoses

  • Keep the initial differential diagnosis quite broad.

  • Quickly narrow down the differential using history and physical exam, and make sure to rule out the emergent diagnoses.

Management and Clinical Pathway

  • If the patient meets the diagnostic criteria for concussion, the majority of the emergency management should involve patient education and counseling.

  • It is important to always maintain a high degree of suspicion for concussion and err on the side of caution when making this diagnosis.

    • If the diagnosis is uncertain, do not let athletes return to sports until they have followed up with their primary care or sports medicine physician.

    • Follow the mantra, “When in doubt, sit them out.”

  • Imaging is not indicated in the emergency department for diagnosis of concussion. However, if the patient has focal neurologic deficits or there is concern for underlying severe head injury, brain imaging should be obtained. If the patient has signs of a traumatic blow to the head or face, consider imaging to rule out underlying pathology.

  • Medication management: Nonsteroidal anti-informatory drugs (NSAIDs) should NOT be taken in the first seventy-two hours after a concussion. This is recommended by the current position statements on concussion in sport because of the theoretical risk of bleeding.4 If the patient has a headache or neck or back pain, acetaminophen should be taken.

  • Brain rest recommendations:

    • The patient should be advised that the more the brain rests, the quicker the recovery. Brain rest entails resting as much as possible, avoiding physical activity, avoiding computer/cellular use, and, when possible, taking one to two days off from work. In general, patients should avoid any activities that make their symptoms worse. While no further damage will ensue from working, texting, or using the brain, it may take slightly longer for symptoms to resolve.1, 4, 13

Table 11.2 Emergent and Common Diagnoses in the Emergency Department

Emergent Diagnoses Common Diagnoses
Intracranial/subarachnoid hemorrhage Simple hematoma
Subdural/epidural hematoma Simple contusion
Second impact syndrome Cervical muscle strains
Chronic traumatic encephalopathy Concussion
Skull fracture Minor head injury
Cervical spine fracture
Spinal cord injury without radiographic abnormality (SCIWORA)

Figure 11.4. Clinical pathway for the adult patient with suspected concussion.


  • Follow-up: Every patient should follow-up with their primary care doctor (PCP), sports medicine specialist, or neurologist approximately one to three days after a concussion is sustained.1, 4, 5

  • Work/athletics recommendations: The more the patient rests the brain, the quicker the recovery will be.1, 4, 5 In addition, stressing the brain with work, studying, reading, and athletics (from increasing the heart rate and blood pressure) may worsen symptoms during and after the activity. If the patient chooses to go to work, it will not cause any further damage to the brain. The patient should not engage in any activity which could potentially risk sustaining a second concussion before fully healing from the current concussion. See the Pediatrics section for school recommendations.

  • Brain rest recommendations: The patient should be advised to avoid cellular phone use (including texting), computer use, television, reading, and any activity which raises the heart rate above 100 beats per minute or increases their blood pressure.

  • Return to work and return to play recommendations: Patients should be advised to obtain clearance to return to sports from their PCP and/or sports medicine physician. It is important that the emergency physician does not clear patients to return to physical activity or sports from the emergency department. General anticipatory guidance may include advising the patient to slowly begin returning to work as tolerated by symptoms. Athletes should not return to play until after they have been completely symptom free for at least forty-eight hours.1, 35, 13 The return to play should be a graded progression of activity so that the patient may gradually ease back into the gym and gradually increase the heart rate over many days without triggering any concussion symptoms. The patient may not return to contact sports until completing return to play progression symptom free and being cleared by either the PCP, sports medicine physician, or neurologist.

  • Return to play progression:

    • Step 1: Light general conditioning (15- to 20-minute light workout).

    • Step 2: General conditioning and sport-specific skill work (individual 30-minute light workout).

    • Step 3: General conditioning and skill work with team (no contact, workout up to 60 minutes).

    • Step 4: General conditioning, skill work, and team drills (no contact, workout up to 75 minutes).

    • Step 5: Full team practice with body contact.


  • Second impact syndrome: This is a rare life-threatening condition that may occur when an individual sustains a second concussion before the brain has completely healed from the first concussion.6, 7.This typically affects young healthy athletes and results in cerebral edema, potential brain herniation, and death.6, 7 It is very important for the emergency physician to educate the patient regarding when to return to play and to warn them of the risk of second impact syndrome, especially with contact sports, while symptoms persist.

  • Chronic traumatic encephalopathy (CTE): This is a rare progressive neuropathological disease that results from repetitive brain trauma.1, 5, 14 It has been described in athletes such as boxers and football players.1, 5, 14 Symptoms of CTE include memory disturbances, behavior and personality changes, and speech and gait abnormalities.1, 5, 14

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Sep 1, 2020 | Posted by in SPORT MEDICINE | Comments Off on Chapter 11 – Concussion
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