Concussion (mild, traumatic brain injury) is a closed head injury due to a direct blow to the head or deceleration of the head from an impulsive force, resulting in a transient change in mental status.
Most common causes are motor vehicle accidents, sports, assaults, and falls.
Diagnosing concussion is difficult based on acute injury characteristics and presenting signs and symptoms.
Headache, mental slowing and fogginess, and memory difficulties are typical symptoms. Symptoms may fluctuate, but typically subside after 1 week to 1 month. Loss of consciousness is not necessary for a positive diagnosis.
Computed tomography scan and magnetic resonance imaging are typically normal in concussive injury.
For uncomplicated cases, physical and cognitive rest is usually sufficient.
Concussion (mild traumatic brain injury) is a closed head injury due to a direct blow to the head or deceleration of the head from an impulsive force that results in a change in mental status. Centers for Disease Control and Prevention: HEADSUP Opens in new window
History and exam
Key diagnostic factors
- direct blow to the head or deceleration of the head from an impulsive force
- previous brain trauma or alcohol misuse
Other diagnostic factors
- feeling foggy/slow
- dizziness/balance problems
- memory difficulties
- normal physical neurologic exam
- abnormalities on neuropsychological testing
- previous brain trauma
- alcohol and drug misuse
- poor neck strength
1st investigations to order
- CT head
Investigations to consider
- MRI head
- functional MRI (fMRI)
- PET, single-photon emission CT (SPECT) of head
- alternative imaging techniques
- anatomic brain imaging techniques
- Moderate/severe traumatic brain injury
- General trauma or injury to the body not involving the head
- Head injury: assessment and early management
- Living guideline for diagnosing and managing pediatric concussion
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