Concussion

Epidemiology & Risk Factors

• Demographics: Athletes (contact sports), elderly (falls), MVAs.
• Risk Factors: Prior concussion (↑ risk & recovery time), anticoagulation (↑ ICH risk).

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Clinical Features

• Mechanism: Reversible functional (not structural) neuronal disturbance.
• Sxs: Headache (most common, sensitivity to light/noise), confusion, anterograde/retrograde amnesia, dizziness, nausea, emotional lability, sleep changes.
  • LOC is NOT required (present in < 10%). c
• PE: Normal focal neuro exam; impaired tandem gait/Romberg; GCS 13–15.

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Diagnosis

• Clinical: Primary dx based on Hx & PE; neuroimaging is not routinely indicated.
• Non-contrast Head CT Indications (Red Flags):
  • GCS < 15 at 2h post-injury.
  • Suspected open/depressed or basilar skull fracture (Battle sign, raccoon eyes, CSF leak).
  • ≥ 2 vomiting episodes, age ≥ 65, anticoagulation, focal neuro deficit, seizure.

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Differential Diagnostics

• Epidural Hematoma: MMA laceration; classic lucid interval; biconvex/lens-shaped hyperdensity (respects suture lines).
• Subdural Hematoma: Bridging vein tear; gradual decline; crescent-shaped hyperdensity (crosses suture lines).
• Diffuse Axonal Injury (DAI): Severe trauma with coma; CT normal or subtle; MRI shows punctate microhemorrhages at gray-white junction.

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Management

1. Immediate: Removal from play; never return to play on the same day.
2. Acute (24–48h): Relative rest (light cognitive/physical activity as tolerated; avoid prolonged isolation/dark room). Acetaminophen for pain (avoid NSAIDs initially; avoid opioids).
3. Graduated Return-to-Play:
   • 6-step protocol (≥ 24h per step; step back if sxs recur):
     • 1. Symptom-limited activity → 2. Light aerobic → 3. Sport-specific non-impact → 4. Non-contact drills → 5. Full contact (requires medical clearance) → 6. Game play.

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Complications

• Second-Impact Syndrome: Rapid, fatal cerebral edema/herniation if a second head injury occurs before recovery.
• Post-Concussion Syndrome (PCS): Persistence of concussion symptoms (e.g., headache, dizziness, cognitive impairment) for weeks to months (typically >3 months) after the initial injury. Symptomatic care only. Most patients recover within 6 months. c
• Chronic Traumatic Encephalopathy (CTE): Tauopathy from repetitive trauma leading to dementia, aggression, and depression.