100+ Free ABPN Brain Injury Medicine Practice Questions

TBI Epidemiology, Biomechanics & Severity

U.S. TBI incidence ~2.8 million/year (CDC). Falls leading cause overall; MVCs in adolescents/young adults; assaults; sports; blast in service members. Biomechanics — linear acceleration (focal contusions, coup/contrecoup), rotational/angular acceleration (diffuse axonal injury at gray-white junction, corpus callosum, dorsolateral midbrain), blast overpressure (primary blast wave). Severity by initial GCS — mild 13-15 (concussion), moderate 9-12, severe 3-8. Duration of LOC, post-traumatic amnesia (PTA, Russell or GOAT), and structural imaging refine classification.

Neuropathology & Primary vs Secondary Injury

Primary injury — diffuse axonal injury (DAI, beta-APP staining, gray-white junction, corpus callosum, dorsolateral pons), cortical contusions (frontal/temporal poles), epidural hematoma (lens-shaped, middle meningeal artery, lucid interval), subdural hematoma (crescentic, bridging veins, elderly/anticoagulated), traumatic SAH, intraparenchymal hemorrhage. Secondary injury cascade — hypoxia, hypotension, excitotoxicity (glutamate/NMDA), oxidative stress, mitochondrial dysfunction, calcium dysregulation, inflammation, cerebral edema (cytotoxic vs vasogenic), elevated ICP, herniation syndromes (uncal, central, subfalcine, tonsillar).

Acute Management & Neurocritical Care

Brain Trauma Foundation 4th edition guidelines (2016) — ICP monitoring for severe TBI with abnormal CT (or with normal CT plus ≥2 of: age >40, motor posturing, SBP <90). Treat ICP >22 mm Hg; target CPP 60-70 mm Hg. Tier 1 (head of bed 30°, sedation/analgesia, normothermia, normocapnia PaCO2 35-40, hyperosmolar — mannitol 0.25-1 g/kg or 3% saline), Tier 2 (CSF drainage via EVD, neuromuscular blockade, mild hyperventilation PaCO2 30-35), Tier 3 (decompressive craniectomy — RESCUEicp 2016 reduced mortality with more vegetative survivors; DECRA 2011 negative for early bifrontal; pentobarbital coma; therapeutic hypothermia 32-34°C — POLAR/Eurotherm negative). Avoid steroids (CRASH 2004 — increased mortality). TXA within 3 h reduces head-injury death (CRASH-3 2019). Seizure prophylaxis with levetiracetam or phenytoin × 7 days for severe TBI.

Neuroimaging in TBI

Non-contrast head CT — first-line for acute TBI. Marshall/Rotterdam CT classifications. Epidural (lens, doesn't cross sutures), subdural (crescent, crosses sutures), tSAH, contusions (frontal/temporal), midline shift, cisternal effacement. Canadian CT Head Rule and New Orleans Criteria for mild TBI. MRI more sensitive — DAI on SWI/GRE (microbleeds at gray-white junction, corpus callosum, dorsolateral brainstem); FLAIR for non-hemorrhagic shear; DWI for ischemia. Diffusion tensor imaging (DTI) for white matter integrity in research. Functional imaging (PET, fMRI) and amyloid/tau PET (CTE research). MR spectroscopy (NAA reduction).

Prognostication & Outcome Scales

Glasgow Outcome Scale (GOS 1-5: dead, vegetative, severe disability, moderate disability, good recovery) and GOS-Extended (GOSE 1-8). Functional Independence Measure (FIM). Disability Rating Scale (DRS). IMPACT and CRASH calculators integrate age, GCS motor, pupils, hypoxia, hypotension, CT features, glucose, hemoglobin, tSAH, EDH for 6-month mortality and unfavorable outcome. Disorders of consciousness — coma, vegetative state/UWS (>1 month — persistent), minimally conscious state (MCS+ language; MCS- non-reflexive movement), emergence (functional object use or communication). Coma Recovery Scale-Revised (CRS-R) is the gold-standard bedside tool.

Concussion, Post-Concussive Syndrome & CTE

Sports concussion — Concussion in Sport Group (Amsterdam 2022, 6th international consensus); SCAT6 (athletes ≥13 y), Child SCAT6 (5-12 y), Sport Concussion Office Assessment Tool (SCOAT6). Symptom clusters — physical (HA, dizziness), cognitive (fog, slowed processing), emotional (irritability, anxiety), sleep. Most resolve within 2 weeks (adults) / 4 weeks (children/adolescents). Persistent post-concussive symptoms beyond 4 weeks → multidisciplinary care (vestibular, cervical, oculomotor, exertional, mood). Sub-symptom threshold aerobic exercise within 24-48 h is now recommended (no longer strict cocoon rest). Second-impact syndrome (rare, catastrophic cerebral edema in adolescents). Chronic traumatic encephalopathy (CTE) — neuropathological diagnosis (hyperphosphorylated tau in neurons/astrocytes around small vessels at sulcal depths); diagnosed only post-mortem; clinically traumatic encephalopathy syndrome (TES) per 2021 NINDS criteria.

Cognitive Rehabilitation

Cognitive domains affected — attention/processing speed, memory, executive function, language/social pragmatics. Evidence-based approaches per ACRM/Cicerone updates: Attention Process Training (APT) for attention; metacognitive strategy training (Goal Management Training, GMT) for executive dysfunction; spaced retrieval and errorless learning for memory; external compensatory aids (smartphones, alarms, notebooks). Comprehensive holistic neuropsychological rehabilitation programs improve community participation. Pharmacologic adjuncts — methylphenidate (attention, processing speed; Whyte 2004), amantadine (arousal/recovery in DOC — Giacino NEJM 2012 in vegetative/MCS 4-16 weeks post-injury), cholinesterase inhibitors (limited evidence).

Behavioral & Emotional Sequelae

Post-TBI agitation peaks during PTA — assess with Agitated Behavior Scale (ABS); environmental management first (quiet room, consistent staff, reduce stimulation); avoid restraints. Pharmacotherapy — propranolol (best evidence per INCOG 2014/2023), amantadine, valproate, atypical antipsychotics (avoid typical antipsychotics and benzodiazepines — worsen recovery and cognition). Depression in 25-50% post-TBI; SSRIs (sertraline) first-line; avoid tricyclics (anticholinergic). Anxiety, PTSD (overlap with mTBI in service members). Pseudobulbar affect — dextromethorphan/quinidine. Personality change, disinhibition (orbitofrontal), apathy (medial frontal/cingulate). Suicide risk elevated 2-4× post-TBI.

Motor, Sensory & Autonomic Deficits

Spasticity — upper motor neuron syndrome with velocity-dependent tone increase; modified Ashworth Scale; treatment hierarchy — stretching/positioning → oral baclofen, tizanidine, dantrolene → focal botulinum toxin → intrathecal baclofen. Avoid benzodiazepines if possible. Cranial neuropathies — anosmia (CN I, cribriform shear, ~20% of moderate-severe TBI), CN VII (temporal bone fracture). Vestibular dysfunction (BPPV, post-traumatic peripheral vestibulopathy, central). Visual — convergence insufficiency, accommodation deficits. Paroxysmal sympathetic hyperactivity (PSH/dysautonomia/'storming') — episodic tachycardia, hypertension, hyperthermia, tachypnea, diaphoresis, dystonic posturing; PSH-Assessment Measure; treatment with morphine, gabapentin, propranolol, clonidine, bromocriptine, intrathecal baclofen.

Post-Traumatic Seizures & Neuroendocrine Dysfunction

Post-traumatic seizures — immediate (<24 h), early (<7 d), late (>7 d, defines post-traumatic epilepsy, PTE). Risk factors for PTE — penetrating injury (>50%), depressed skull fracture, intracranial hematoma requiring evacuation, early seizure, GCS <10. Prophylaxis with levetiracetam or phenytoin reduces early but NOT late seizures (Class I). Levetiracetam preferred (no monitoring, fewer interactions). Neuroendocrine — anterior hypopituitarism in 15-50% post moderate-severe TBI; growth hormone deficiency most common (fatigue, low quality of life); secondary hypogonadism, hypothyroidism, adrenal insufficiency; screen 3-6 months post-injury. Posterior pituitary — DI (hypernatremia, dilute urine, treat with DDAVP), SIADH (euvolemic hyponatremia, fluid restriction), cerebral salt wasting (hyponatremia + hypovolemia, treat with salt and fluid replacement).

Pediatric TBI & Abusive Head Trauma

Pediatric TBI — leading cause of death/disability in children. PECARN rule for clinically important TBI in children <2 y and 2-18 y avoids unnecessary CT. Abusive head trauma (AHT) — formerly 'shaken baby'; classic triad (subdural hematoma, retinal hemorrhages, encephalopathy); look for skull fractures, posterior rib fractures, metaphyseal corner fractures, bruising in non-cruising infants (TEN-4 FACES rule). Mandatory reporting. Heterotopic ossification — peri-articular ectopic bone (hip, knee, elbow, shoulder); 4-12 weeks post-injury; alkaline phosphatase, triple-phase bone scan; treat with NSAIDs (indomethacin) for prophylaxis, ROM, surgical resection when mature. Pediatric concussion — generally longer recovery than adults (up to 4 weeks).

Blast & Military TBI

Blast injury categories — primary (overpressure wave; pulmonary, tympanic membrane, brain), secondary (penetrating fragments), tertiary (body propelled), quaternary (burns, inhalation, crush). Most service-member TBI is mild and from blast (IED). High overlap with PTSD — symptom overlap (sleep, irritability, concentration). DoD severity classification mirrors civilian (mild/moderate/severe) with addition of penetrating. VA/DoD clinical practice guideline for mild TBI/concussion 2021 — symptom-targeted treatment, gradual return-to-activity, treat comorbid PTSD/pain/sleep.

Return-to-Play, Return-to-Duty & Pharmacotherapy

Return-to-play (RTP) per Amsterdam 2022 CISG — 6-step graduated protocol (symptom-limited activity → light aerobic → sport-specific → non-contact training → full-contact practice → return to play); each step ≥24 h; strategic rest 24-48 h then early sub-symptom-threshold aerobic exercise. Same-day return prohibited for any suspected concussion. Pharmacotherapy summary — amantadine 200-400 mg/d for DOC and arousal (Giacino 2012); methylphenidate for attention/processing; sertraline for depression; propranolol for agitation/PSH; levetiracetam for seizure prophylaxis; melatonin for sleep; avoid benzodiazepines, typical antipsychotics, anticholinergics, and prophylactic phenytoin beyond 7 days.