How can I differentiate between concussion and more serious traumatic brain injuries in a primary care assessment?

During a primary care assessment, differentiating concussion from more serious traumatic brain injuries (TBI) relies on careful clinical evaluation of symptoms, signs, and risk factors. Concussion is characterized by a Glasgow Coma Scale (GCS) score of 15, transient neurological symptoms such as headache, dizziness, nausea, amnesia (antegrade or retrograde), and cognitive difficulties without focal neurological deficits or structural brain injury on imaging ¹. More serious TBI is suspected if any of the following are present: GCS less than 15 on initial assessment, persistent or worsening confusion, focal neurological signs, seizures, suspected penetrating injury, cerebrospinal fluid leak, or deterioration in neurological status ¹,².

Key clinical features that warrant urgent hospital referral and imaging (usually CT head) include any loss of consciousness, amnesia lasting more than 5 minutes, persistent headache, vomiting, seizures, high-energy mechanism of injury, anticoagulant use, intoxication, or any suspicion of skull fracture or neurological deficit ¹,². The presence of these features suggests a higher risk of intracranial complications beyond concussion and mandates urgent investigation ¹,².

In contrast, concussion symptoms often include transient confusion, headache, dizziness, visual disturbances, and cognitive 'brain fog' but without focal neurological deficits or reduced consciousness beyond brief loss ¹. The GCS remains 15, and neurological examination is normal. Post-concussion symptoms may persist but do not indicate structural brain injury ¹.

Clinical decision rules embedded in UK guidelines emphasize the importance of GCS assessment, neurological examination, and identification of risk factors to triage patients appropriately ¹,². CT imaging is the primary investigation for suspected clinically important TBI, whereas concussion is a clinical diagnosis without imaging abnormalities ². MRI is not routinely used acutely but may provide additional prognostic information in selected cases ².

Early education and reassurance about concussion symptoms and expected recovery are important, alongside advice on gradual return to normal activities and monitoring for any deterioration ¹. Persistent or worsening symptoms beyond the acute phase may require specialist referral ¹.

In summary, primary care differentiation hinges on GCS scoring, neurological examination, and identification of red flags for serious injury requiring urgent imaging and referral, while concussion is diagnosed clinically in the absence of these red flags ¹,².