27.2 Concussion & Minor Closed Head Injury Evaluation

ABFM Family Medicine Certification Study Guide Exam

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7 Chapter 7: Pediatric Health Maintenance & Surveillance

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17 Chapter 17: Neurologic Emergencies: Stroke & Altered Consciousness

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18 Chapter 18: Neurologic Trauma & Acute Cranial Emergencies

18.1 Concussion, Moderate-to-Severe TBI & Intracranial Injury 18.2 Thunderclap & Acute Severe Secondary Headaches 18.3 Acute Ophthalmologic Emergencies

19 Chapter 19: Acute Abdominal, Pelvic & Gastrointestinal Emergencies

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20 Chapter 20: Acute Pulmonary & Airway Emergencies

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21 Chapter 21: Acute Traumatic Injuries & Wound Care

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22 Chapter 22: Acute Orthopedic & Musculoskeletal Emergencies

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23 Chapter 23: Severe Infections, Sepsis & Systemic Emergencies

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24 Chapter 24: Metabolic, Endocrine & Electrolyte Emergencies

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25 Chapter 25: Hematologic, Urologic & Dental Emergencies

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26 Chapter 26: Psychiatric, Behavioral & Obstetric/Gynecologic Emergencies

26.1 Suicidal Ideation, Acute Agitation & Behavioral Emergencies 26.2 Acute Physical & Sexual Assault Care 26.3 Life-Threatening Vaginal Bleeding & Ectopic Pregnancy 26.4 Environmental Heat Stroke & Severe Hypothermia

27 Chapter 27: Acute Head, Neck & Neurologic Symptoms

27.1 Primary Acute Headaches: Migraine, Tension & Cluster 27.2 Concussion & Minor Closed Head Injury Evaluation 27.3 Transient Ischemic Attack Evaluation & ABCD2 Risk Scoring

28 Chapter 28: Acute Cranial Nerves, Hearing & Sensory Symptoms

28.1 Peripheral Neuropathies: Bell's Palsy, Carpal Tunnel & Radiculopathy 28.2 Acute Tinnitus, Sudden Sensorineural Hearing Loss & Cerumen Impaction 28.3 Acute Dizziness, Benign Paroxysmal Positional Vertigo & Vestibular Neuritis

29 Chapter 29: Acute Upper Respiratory Tract Infections

29.1 Acute Viral Rhinosinusitis vs. Bacterial Rhinosinusitis 29.2 Acute Pharyngitis: Group A Streptococcus & Centor Criteria 29.3 Acute Otitis Media, Otitis Externa & Serous Effusion

30 Chapter 30: Acute Lower Respiratory Infections & Cough

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31 Chapter 31: Allergic, Nasal & Non-Infectious Pulmonary Conditions

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32 Chapter 32: Acute Chest, Cardiac & Vascular Symptoms

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33 Chapter 33: Acute Upper Gastrointestinal Conditions

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35 Chapter 35: Inflammatory, Functional & Malabsorptive GI Disorders

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36 Chapter 36: Acute Abdominal, Hepatic & Biliary Disorders

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37 Chapter 37: Acute Abdominal Wall, Hernias & Dental Conditions

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38 Chapter 38: Acute Infectious Dermatoses

38.1 Bacterial Skin Infections: Impetigo, Cellulitis & Cutaneous Abscesses 38.2 Fungal Skin Infections: Tinea Corporis, Cruris, Pedis & Onychomycosis 38.3 Viral Cutaneous Infections: Herpes Simplex, Zoster & Molluscum Contagiosum

39 Chapter 39: Inflammatory, Allergic & Autoimmune Dermatoses

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40 Chapter 40: Acute Shoulder, Elbow & Upper Extremity Injuries

40.1 Rotator Cuff Pathology, Tendinopathy & Shoulder Impingement 40.2 Lateral & Medial Epicondylitis, Olecranon Bursitis & Elbow Sprains 40.3 Wrist & Hand Soft-Tissue Injuries: De Quervain, TFCC & Finger Sprains

41 Chapter 41: Acute Knee, Ankle & Lower Extremity Injuries

41.1 Meniscal Tears, Ligamentous Knee Injuries & Patellofemoral Pain 41.2 Ankle Sprains, Ottawa Ankle Rules & Achilles Tendinopathy 41.3 Plantar Fasciitis, Shin Splints & Overuse Syndromes

42 Chapter 42: Acute Ambulatory Fractures & Dislocations

42.1 Distal Radius, Scaphoid & Common Upper Extremity Fractures 42.2 Metatarsal, Clavicle & Common Lower Extremity Fractures 42.3 Joint Dislocation Management: Nursemaid's Elbow & Shoulder Subluxation

43 Chapter 43: Acute Axial Musculoskeletal Pain & Falls

43.1 Acute Low Back Pain: Red Flags, Strain & Disc Herniation 43.2 Acute Cervical Strain, Whiplash & Axial Neck Pain 43.3 Evaluation of Falls in Ambulatory & Older Patients

44 Chapter 44: Acute Inflammatory Arthropathies & Generalized Pain

44.1 Acute Inflammatory Arthritis & Spondyloarthropathies 44.2 Myalgias, Rhabdomyolysis & Post-Viral Pain Syndromes 44.3 Acute Non-Headache Pain Management Strategies

45 Chapter 45: Acute Renal, Urinary & Genitourinary Conditions

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46 Chapter 46: Acute Male Genitourinary & Prostatic Conditions

46.1 Acute Prostatitis, Epididymitis & Orchitis 46.2 Acute Scrotal Pain: Torsion vs Appendage, BPH & Male Genital Emergencies 46.3 Acute Urinary Retention & Incontinence Evaluation

47 Chapter 47: Acute Women's Health & Early Pregnancy Care

47.1 Early Pregnancy Diagnosis, Dating & Initial Complications 47.2 Abnormal Uterine Bleeding & Acute Menstrual Disorders 47.3 Premenstrual Syndrome & Premenstrual Dysphoric Disorder

48 Chapter 48: Breast Disorders, STIs & Pediatric Elimination

48.1 Palpable Breast Mass, Mastitis & Nipple Discharge 48.2 Sexually Transmitted Infections: Diagnosis, Staging & CDC Guidelines 48.3 Pediatric Enuresis & Encopresis

49 Chapter 49: Systemic Signs, Metabolic Dysregulation & Miscellaneous Infections

49.1 Acute Fever, Sepsis Screening & FUO in Primary Care 49.2 Acute Hyperglycemia & Symptomatic Hypoglycemia 49.3 Electrolyte Abnormalities: Mild-to-Moderate Disturbances 49.4 Vector-Borne, Tick-Borne & Rickettsial Illnesses

50 Chapter 50: Chronic Cardiovascular Diseases: Hypertension & Ischemia

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51 Chapter 51: Chronic Vascular, Valvular & Dyslipidemic Diseases

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52 Chapter 52: Chronic Respiratory Diseases: Asthma & COPD

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53 Chapter 53: Chronic Metabolic Diseases: Diabetes Mellitus

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54 Chapter 54: Obesity, Nutrition & Metabolic Bone Diseases

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55 Chapter 55: Chronic Endocrine Disorders

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56 Chapter 56: Chronic Kidney Disease & Venous Disorders

56.1 Chronic Kidney Disease: KDIGO Staging & Renoprotective Therapy 56.2 Chronic Venous Insufficiency, Stasis Dermatitis & Lymphedema 56.3 Chronic Electrolyte & Acid-Base Management in CKD

57 Chapter 57: Chronic Gastrointestinal & Hepatic Diseases

57.1 Gastroesophageal Reflux Disease, Barrett's Esophagus & Dyspepsia 57.2 Chronic Liver Disease: MASLD/NAFLD, Cirrhosis & Portal Hypertension 57.3 Viral Hepatitis B & C: Long-Term Monitoring & DAA Therapy

58 Chapter 58: Colorectal Surveillance & Chronic Pancreaticobiliary Care

58.1 Post-Polypectomy Colorectal Polyp Surveillance Guidelines 58.2 Chronic Pancreatitis & Exocrine Pancreatic Insufficiency 58.3 Chronic Nausea, Gastroparesis & Functional GI Disorders

59 Chapter 59: Chronic Musculoskeletal & Rheumatologic Disorders

59.1 Osteoarthritis: Hip, Knee & Hand Management 59.2 Spinal Conditions: Spinal Stenosis, Spondylolisthesis & Compression Fractures 59.3 Chronic Myopathies & Fibromyalgia Syndrome

60 Chapter 60: Chronic Neurologic & Neurodegenerative Disorders

60.1 Dementia: Alzheimer's, Vascular & Lewy Body Disease 60.2 Parkinson's Disease & Essential Tremor 60.3 Epilepsy: Chronic Antiseizure Medications & Post-Stroke Care

61 Chapter 61: Chronic Peripheral Nerves, Pain & Sensory Disorders

61.1 Diabetic & Chronic Peripheral Neuropathies 61.2 Chronic Pain Syndromes & Chronic Daily Headaches 61.3 Chronic Tinnitus, Presbycusis & Persistent Dizziness

62 Chapter 62: Chronic Psychiatric Disorders

62.1 Major Depressive Disorder & Generalized Anxiety Disorder 62.2 Bipolar Disorder: Maintenance Pharmacotherapy & Lithium Monitoring 62.3 Adult & Pediatric Attention-Deficit/Hyperactivity Disorder

63 Chapter 63: Chronic Behavioral Health & Neurodevelopmental Conditions

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64 Chapter 64: Chronic Substance Use Disorders & Tobacco Cessation

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65 Chapter 65: Chronic Dermatologic Conditions

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66 Chapter 66: Chronic Reproductive, Infectious & Geriatric Special Care

66.1 Chronic Menstrual Disorders, Infertility & Sexual Dysfunction 66.2 Menopause Management & Hormone Replacement Therapy 66.3 Chronic HIV Infection Management & Primary Care Integration 66.4 Gender-Affirming Primary Care & Hormone Therapy 66.5 Advance Care Planning, Palliative Care & End-of-Life Symptom Control

67 Chapter 67: Continuity Care: Sleep, Fatigue, Cancer, Pregnancy & the Adult Preventive Visit

67.1 Chronic Insomnia & Obstructive Sleep Apnea 67.2 Chronic Malaise, Fatigue & ME/CFS 67.3 Primary Care During Cancer Treatment & Survivorship 67.4 Routine Prenatal Care & Longitudinal Pregnancy Management 67.5 The Periodic Adult Health Examination & Medicare Annual Wellness Visit

27.2 Concussion & Minor Closed Head Injury Evaluation

Key Takeaways Explain This Topic AI

Concussion is a biomechanically induced functional brain disturbance driven by a neurometabolic cascade: mechanical membrane deformation triggers indiscriminate glutamate release, massive potassium efflux, and calcium influx, driving an ATP-exhausting hypermetabolic pump crisis alongside transient cerebral hypoperfusion.

The Vestibular / Ocular Motor Screening (VOMS) tool assesses smooth pursuits, horizontal/vertical saccades, near point of convergence (NPC >5 cm is abnormal), vestibulo-ocular reflex (VOR), and visual motion sensitivity (VMS), identifying specific functional deficits that predict protracted recovery.

Strict prolonged rest in a dark room ('cocoon therapy') is obsolete and actively harmful; current international consensus mandates relative rest for only the first 24 to 48 hours, followed by progressive, symptom-limited resumption of daily activities and sub-symptom aerobic exercise (walking, stationary cycling).

Return-to-Learn (RTL) must precede full Return-to-Sport (RTS); athletes must achieve full-time classroom attendance without academic accommodations before receiving medical clearance for full-contact practice (Stage 5).

Persistent Post-Concussive Symptoms (PPCS) lasting >4 weeks in youth or >3 months in adults require targeted multimodal rehabilitation, including vestibular physical therapy, vision therapy, Buffalo Concussion Treadmill Testing for heart-rate-guided exercise prescriptions, and cognitive behavioral therapy.

Last updated: September 2026

Concussion & Minor Closed Head Injury: Biomechanics & Neurometabolic Cascade

Concussion, categorized under the broader diagnosis of Mild Traumatic Brain Injury (mTBI) , is defined by the Concussion in Sport Group (CISG) as a traumatic brain injury induced by biomechanical forces. Concussion represents a complex functional disturbance of brain metabolism rather than a macrostructural anatomical injury; consequently, standard neuroimaging modalities (head CT and routine brain MRI) demonstrate no visible structural abnormalities.

Biomechanics of Closed Head Injury

Concussion can result from a direct blow to the head, face, or neck, or from an indirect impulsive force transmitted to the head from an impact elsewhere on the body (e.g., severe torso collision, blast wave, or whiplash deceleration). Biomechanical studies demonstrate that rotational (angular) acceleration-deceleration forces are substantially more injurious than pure linear forces. Rotational forces induce deep tissue shear strain, twisting and stretching axons and microvascular structures, particularly at tissue interfaces between the cerebral cortex and deep subcortical/brainstem structures.

The Neurometabolic Cascade of Concussion

The pathophysiological hallmark of concussion is a temporary cellular energy crisis governed by the Giza-Hovda neurometabolic cascade : THE NEUROMETABOLIC CASCADE OF CONCUSSION

Biomechanical Impact & Rotational Shear Forces
│
▼
Mechanical Stretching of Neuronal Cell Membranes
│
▼
Indiscriminate Massive Presynaptic Glutamate Release
│
▼
Widespread Activation of Postsynaptic NMDA & AMPA Receptors
│
┌───────────────────────────┴───────────────────────────┐
▼ ▼
Massive Potassium (K+) Efflux Massive Calcium (Ca2+) Influx
into Extracellular Space into Intracellular Space
│ │
▼ ▼
Spreading Membrane Depolarization Mitochondrial Ca2+ Sequestration
│ │
▼ ▼
Hyperactivation of Na+/K+-ATPase Pumps Mitochondrial Swelling & Failure
(Massive ATP Consumption) (Severely Crippled ATP Production)
│ │
▼ ▼
SURGE IN GLUCOSE CONSUMPTION CYTOSKELETON BREAKDOWN
(HYPERGLYCOLYSIS) (Calpain/Caspase Activation,
│ Axonal Microtubule Disassembly)
└───────────────────────────┬───────────────────────────┘
▼
CRITICAL CELLULAR ENERGY MISMATCH
("ATP Exhaustion / Metabolic Crisis")
│
▼
Concurrent Cerebral Hypoperfusion
(30-50% Reduction in Cerebral Blood Flow)
│
▼
Vulnerable Window for Second-Impact Syndrome

Membrane Deformation & Ionic Derangement : Mechanical tensile strain deforms axonal and neuronal membranes, opening stretch-sensitive channels. This causes an immediate, massive release of excitatory amino acids—primarily glutamate —into the extracellular synaptic space.

Excitotoxicity & Potassium Efflux : Glutamate binds avidly to postsynaptic NMDA and AMPA receptors, triggering massive potassium (K+) efflux into the extracellular space and uncontrolled calcium (Ca2+) and sodium (Na+) influx into neurons. Extracellular potassium accumulation causes widespread neuronal depolarization, followed by a wave of functional cortical depression.

The Hypermetabolic Energy Crisis : To restore resting membrane potentials, membrane-bound ATP-dependent Na+/K+-ATPase pumps are driven to maximal hyperactive capacity . This drives a compensatory surge in glucose metabolism ( hyperglycolysis ).

Mitochondrial Dysfunction & ATP Exhaustion : Concurrently, excessive intracellular calcium is sequestered into neuronal mitochondria. Calcium overload leads to mitochondrial swelling, uncoupling of oxidative phosphorylation, and impaired ATP generation. The neuron faces a disastrous mismatch: dramatically increased demand for ATP alongside severely compromised ATP synthesis , exhausting cellular energy reserves.

Transient Cerebral Hypoperfusion : Compounding this metabolic crisis, perivascular microvascular dysregulation causes a 30% to 50% reduction in resting cerebral blood flow (CBF) that persists for days to weeks. The brain is starved of glucose and oxygen precisely when its metabolic requirement is maximal.

Second-Impact Syndrome (SIS) : Occurs when an individual (most commonly an adolescent or young adult <21 years) sustains a second closed head injury before the metabolic cascade of the first concussion has resolved. Autoregulation of cerebral blood flow catastrophically fails, precipitating rapid vascular engorgement, diffuse malignant cerebral edema, brainstem uncal herniation, and death within 2 to 5 minutes (mortality approaches 50-100%). This underlines the absolute mandate: an athlete must NEVER return to collision sports while concussive symptoms persist .

Clinical Assessment in Ambulatory Primary Care: SCAT6 & Physical Examination

Concussion diagnosis is clinical. No single test, biomarker, or imaging study establishes or excludes concussion. Ambulatory evaluation requires a multi-domain assessment utilizing standardized instruments such as the Sport Concussion Assessment Tool 6 (SCAT6) for individuals aged ≥13 years, or the Child SCAT6 for ages 5 to 12 years.

The Multi-Domain Concussion Symptom Inventory

Symptoms should be categorized into four primary clinical domains:

Somatic / Physical : Headache (>80% of concussions), dizziness/vertigo (>60%), light sensitivity (photophobia), sound sensitivity (phonophobia), nausea, balance instability, visual blurring, and neck pain.

Cognitive : Subjective "fogginess" or feeling in a cloud, slowed processing speed, difficulty concentrating, short-term memory impairment, and confusion.

Emotional / Affective : Irritability, emotional lability, unexpected sadness, nervousness, and anxiety.

Sleep / Arousal : Drowsiness, daytime fatigue, insomnia, waking frequently, or sleeping significantly more or less than normal.

Cervical Spine Clearance & Neurologic Examination

Cervical Spine Clearance : Any patient presenting after closed head trauma must be evaluated for cervical spine injury using the Canadian C-Spine Rule or NEXUS criteria . Palpate the entire midline posterior cervical spinous processes for bony tenderness, assess for paraspinal muscle spasm, and evaluate active neck rotation (at least 45° left and right). Midline bony tenderness or paresthesias requires immediate cervical immobilization and imaging.

Neurological Exam : Evaluate cranial nerves III, IV, and VI (extraocular movements, pupillary symmetry and reactivity), facial sensation/symmetry, hearing, motor strength, deep tendon reflexes, and sensory symmetry.

Vestibular / Ocular Motor Screening (VOMS)

The VOMS is a brief, highly sensitive 5-minute bedside assessment tool that evaluates systems frequently disrupted by concussive shear injury. Each test records baseline and provoked symptoms (headache, dizziness, nausea, fogginess on a 0-10 scale): VESTIBULAR / OCULAR MOTOR SCREENING (VOMS)

1. SMOOTH PURSUITS
Examiner moves target smoothly horizontally and vertically (14-point font)
Patient tracks with eyes only while keeping head stationary
Abnormal: Saccadic intrusions, gaze-evoked nystagmus, symptom provocation

2. SACCADES (Horizontal & Vertical)
Patient rapidly shifts gaze between two targets 3 feet apart (at 30°)
10 repetitions horizontally, 10 repetitions vertically
Abnormal: Latency, dysmetria (overshooting/undershooting), symptom provocation

3. NEAR POINT OF CONVERGENCE (NPC)
Slowly move visual target toward the bridge of the nose
Measure distance (in cm) from nose where patient reports double vision (diplopia)
or where examiner notes outward deviation of one eye (repeat x 3, take average)
CLINICAL THRESHOLD: NPC > 5 cm is ABNORMAL (Convergence Insufficiency)

4. VESTIBULO-OCULAR REFLEX (VOR - Horizontal & Vertical)
Patient fixates gaze on central target while rapidly rotating head 20° side-to-side
to a metronome at 180 beats/min for 10 repetitions (repeat vertically)
Abnormal: Inability to keep target focused, symptom provocation

5. VISUAL MOTION SENSITIVITY (VMS)
Patient holds arms outstretched with thumbs touching, fixating eyes on thumbs
Rotates head, eyes, and torso together 90° left and right to a metronome at 50 bpm
Abnormal: Severe dizziness, nausea, or motion sickness (vestibular-visual mismatch)

Clinical Utility : An abnormal Near Point of Convergence (NPC >5 cm) or provoked symptoms on VOR/VMS testing predicts a significantly protracted clinical recovery and guides early referral to vestibular and vision physical therapy.

Balance Error Scoring System (BESS)

The BESS test assesses postural stability. It evaluates three stances— double-leg stance (feet touching), single-leg stance (standing on non-dominant foot with hip flexed 30° and knee flexed 45°), and tandem stance (non-dominant foot directly behind dominant foot heel-to-toe)—tested for 20 seconds each on a firm surface and on a medium-density foam pad (6 trials total), with eyes closed and hands resting on the iliac crests.

Errors Counted (max 10 per trial) : Opening eyes, lifting hands off iliac crests, stepping/stumbling/falling, moving hips into >30° abduction/flexion, lifting forefoot or heel off the surface, or remaining out of testing position for >5 seconds.

Neuroimaging Red Flags & Clinical Decision Rules

Routine neuroimaging is NOT indicated for uncomplicated concussion. Imaging should be strictly reserved for patients with suspected structural intracranial pathology (e.g., acute subdural hematoma, epidural hematoma, traumatic subarachnoid hemorrhage, intraparenchymal contusion, or depressed skull fracture).

The Canadian CT Head Rule (CCHR) for Adults

Applies to patients aged 16 to 65 presenting with blunt head injury who experienced witnessed loss of consciousness, amnesia, or confusion, with Glasgow Coma Scale (GCS) score 13 to 15: CANADIAN CT HEAD RULE (CCHR)

HIGH-RISK CRITERIA (CT Mandated to Rule Out Neurosurgical Intervention):

1. GCS < 15 at 2 hours post-injury
2. Suspected open or depressed skull fracture (palpable step-off)

3. Any clinical sign of basilar skull fracture:

Hemotympanum (blood behind tympanic membrane)
"Battle's Sign" (ecchymosis over mastoid process)
"Raccoon Eyes" (bilateral periorbital ecchymosis)
CSF otorrhea or CSF rhinorrhea
4. Two or more episodes of vomiting
5. Age ≥ 65 years

MEDIUM-RISK CRITERIA (CT Recommended to Rule Out Brain Injury):

6. Retrograde amnesia for events occurring > 30 minutes prior to impact

7. Dangerous injury mechanism:

Pedestrian struck by motor vehicle
Occupant ejected from motor vehicle
Fall from an elevation > 3 feet or > 5 stairs
Pediatric Decision Rules: The PECARN Criteria

In pediatric patients, the PECARN (Pediatric Emergency Care Applied Research Network) decision rules provide near 100% sensitivity for clinically important traumatic brain injury (ciTBI), minimizing unnecessary radiation exposure:

Children < 2 years : Immediate non-contrast CT indicated for GCS <15, palpable skull fracture, or altered mental status (agitation, lethargy, slow response). Observation vs. CT considered for non-frontal scalp hematoma, LOC >5 seconds, severe mechanism, or parental concern of abnormal behavior.

Children 2 to 18 years : Immediate non-contrast CT indicated for GCS <15, signs of basilar skull fracture, or altered mental status. Observation vs. CT considered for history of vomiting, severe headache, LOC, or dangerous mechanism.

Immediate Emergency Transfer Red Flags

Any of the following clinical signs in clinic requires immediate 911 activation and emergency neuroimaging:

Glasgow Coma Scale score <15 at 2 hours post-injury;
Unequal pupils or sluggish pupillary light reactivity;
Progressively worsening, severe headache;
Repeated episodes of vomiting (≥2 episodes);
Progressive lethargy or inability to awaken the patient;
Post-traumatic seizures or focal motor twitching;
New focal neurologic deficits (limb weakness, numbness, aphasia);

Concurrent therapeutic anticoagulation or known coagulopathy.

Outpatient Recovery Paradigm: Active Rehabilitation vs. "Cocoon Therapy"

For decades, conventional medical advice instructed concussed patients to stay in a dark, silent room with zero sensory stimuli, no screens, no reading, and strict physical rest until every symptom had completely resolved—a practice colloquially termed "cocoon therapy" .

The Demise of "Cocoon Therapy"

Landmark randomized clinical trials (Thomas et al., Grool et al., Leddy et al.) demonstrated that strict, prolonged physical and cognitive rest beyond 48 hours is detrimental to recovery . Prolonged dark-room rest fosters social isolation, academic anxiety, somatic hypervigilance, secondary depression, and cardiovascular deconditioning, significantly increasing the risk of Persistent Post-Concussive Symptoms (PPCS).

The 2022 Amsterdam International Consensus Paradigm

The modern evidence-based protocol established by the 6th International Conference on Concussion in Sport (Amsterdam 2022) mandates:

Relative Rest for 24 to 48 Hours Only : The patient should engage in light, quiet home activities (conversing, relaxing, gentle walking) while avoiding strenuous physical exercise, contact sports, and excessive screen time during the acute metabolic vulnerable window.

Gradual Resumption of Activity After 48 Hours : Following the initial 24 to 48 hours, patients are actively encouraged to begin symptom-limited cognitive activity and sub-symptom aerobic exercise (e.g., brisk walking, stationary upright cycling). Light physical activity promotes autonomic nervous system balance, improves cerebral autoregulation, and stimulates neurogenesis and brain-derived neurotrophic factor (BDNF).

The "Mild Exacerbation" Rule : Light activity is considered safe if it causes only a mild, brief increase in symptoms (defined as an increase of ≤2 points on a 0-10 scale that returns to baseline within 1 hour). If symptoms spike severely, the patient pauses, rests, and restarts at a lower intensity.

Return-to-Learn (RTL) Protocol

Cognitive recovery must proceed in parallel with physical recovery. Cognitive exertion should be reintroduced in a stepwise fashion before returning to full physical sports. RETURN-TO-LEARN (RTL) PROGRESSION

STEP 1: Daily Activities at Home
Typical daily activities at home that do not provoke symptoms
Screen-free reading, light drawing, conversation in 10-15 minute blocks
Goal: Gradual cognitive reintroduction

STEP 2: School Activities at Home
Homework assignments, reading, or computer tasks at home in 20-30 min blocks
Built-in 15-minute rest breaks; stop if symptoms flare
Goal: Increase cognitive tolerance

STEP 3: Return to School Part-Time
Attend school for half-days or selected core classes
Academic Accommodations: Built-in rest breaks in nurse's office, quiet environment,
avoidance of noisy spaces (cafeteria, gymnasium, band room), no exams
Goal: Social reintegration and classroom tolerance

STEP 4: Return to School Full-Time with Accommodations
Attend full school day with modified workload
Accommodations: Extended testing time (1.5x), postponed standardized testing,
reduced homework volume, excused from physical education (PE)
Goal: Full academic schedule tolerance

STEP 5: Full Academic Return (Normal Workload)
Full-time school attendance with complete academic workload and standard testing
No academic accommodations needed
MANDATORY CRITERION: Step 5 MUST be achieved before clearing for Stage 5 RTS

THE GOLDEN RULE OF CONCUSSION CLEARANCE (HIGH-YIELD BOARD PEARL) : Full Return-to-Learn MUST precede full Return-to-Sport . A student-athlete can never be cleared for full-contact sports practice (Stage 5 RTS) or competitive matches (Stage 6 RTS) while still receiving academic accommodations or attending school part-time.

The 6-Stage Return-to-Sport (RTS) Progression

Return-to-Sport follows a strict, 6-stage stepwise continuum. Each stage requires a minimum of 24 hours . If concussive symptoms recur or worsen during or following any stage, the athlete must stop, rest for 24 hours until symptoms return to baseline, and then drop back to the previously tolerated asymptomatic stage. 6-STAGE RETURN-TO-SPORT (RTS) PROTOCOL

STAGE 1: Symptom-Limited Activity
Daily activities that do not provoke symptoms (walking, light household tasks)
Objective: Reintroduce normal daily routine

STAGE 2: Light Aerobic Exercise
15-20 minutes of walking, stationary cycling, or light jogging
Target heart rate: < 70% of maximum predicted heart rate
STRICTLY PROHIBITED: Resistance training, weightlifting, jumping, head impacts
Objective: Increase heart rate safely without symptom exacerbation

STAGE 3: Sport-Specific Exercise
Running drills in soccer, skating drills in hockey, throwing drills in baseball
Multi-directional movement without risk of contact
STRICTLY PROHIBITED: Contact drills, heading soccer balls, tackling, body checking
Objective: Add movement and sport-specific motor patterns

STAGE 4: Non-Contact Training Drills
Complex sport drills (passing drills, tactical plays, shooting drills)
Progressive resistance training / weightlifting may begin
Objective: Restore coordination, sport-specific skills, and cognitive processing

STAGE 5: Full-Contact Practice
MANDATORY PHYSICIAN CLEARANCE: Written clearance by licensed healthcare provider
Athlete participates in regular team practice with normal body contact and tackling
Student must already be attending full-time school with zero accommodations
Objective: Restore confidence and assess functional readiness under contact conditions

STAGE 6: Return to Competition
Normal, unrestricted participation in competitive games, matches, and tournaments
Objective: Full athletic resumption
Persistent Post-Concussive Symptoms (PPCS) & Targeted Rehabilitation

Persistent Post-Concussive Symptoms (PPCS) is defined as the persistence of concussive physical, cognitive, or affective symptoms lasting >4 weeks in children and adolescents (<18 years) or >3 months in adults (affecting approximately 15% to 30% of concussion patients).

Clinical Phenotypes & Targeted Therapies

Modern management recognizes that PPCS is not a monolithic entity, but a collection of distinct, overlapping clinical phenotypes requiring targeted multidisciplinary interventions:

Cervicogenic Phenotype :

Pathology : Whiplash injury to cervical spine facet joints and paraspinal soft tissues generating referred cervicogenic headaches and dizziness;

Treatment : Cervical manual physical therapy, deep neck flexor strengthening, and trigger point dry needling.

Vestibular & Ocular-Motor Phenotypes :

Pathology : Vestibular-ocular mismatch, convergence insufficiency (NPC >5 cm), saccadic dysmetria, visual motion sensitivity;

Treatment : Formal vestibular physical therapy (gaze stabilization exercises, habituation) and specialized vision therapy (orthoptic exercises such as pencil push-ups and Brock string training).

Physiologic Autonomic / Exercise Intolerance Phenotype :

Pathology : Persistent autonomic nervous system dysregulation and impaired cerebral blood flow autoregulation;

Diagnostic Evaluation : Buffalo Concussion Treadmill Test (BCTT) : A standardized graded treadmill exercise test where heart rate and symptoms are monitored every minute until symptom exacerbation occurs;

Treatment : Prescription of sub-symptom threshold aerobic exercise (exercising at 80% to 90% of the heart rate threshold achieved on the BCTT for 20 minutes daily, 5-6 days per week), which accelerates autonomic recovery.

Cognitive / Mood / Affective Phenotype :

Pathology : Secondary reactive depression, illness anxiety, insomnia, and somatic hypervigilance;

Treatment : Cognitive Behavioral Therapy (CBT) , sleep hygiene optimization (melatonin 3-5 mg at bedtime), and judicious pharmacotherapy (e.g., SSRIs for secondary mood disorders; amitriptyline for concurrent insomnia and post-traumatic headache).