Head Injuries, Brain Anatomy, and Concussion Management

Vocabulary review covering cranial and brain anatomy, classifications and severity scales of traumatic brain injuries (TBI), concussion evaluation protocols, signs and symptoms, and maxillofacial injuries.

Medulla Oblongata

Part of the brain stem that functions as the cardiac, respiratory, and vasomotor control center.

Pons

Structure of the brain stem that influences respiration.

Midbrain

Brain stem structure that serves as a relay center for visual and auditory impulses.

Thalamus

Component of the diencephalon involved in processing sensations, emotions, and alerting mechanisms.

Hypothalamus

Diencephalic structure responsible for regulating body temperature, water balance, sleep-cycle, and appetite.

Cerebellum

Brain structure that regulates muscle coordination, equilibrium, and posture.

Frontal Lobe

Cerebral lobe responsible for smell, reasoning, behavior, and memory.

Parietal Lobe

Cerebral lobe responsible for processing sensation, intellect, and reasoning.

Temporal Lobe

Cerebral lobe involved in hearing, emotion, and memory.

Occipital Lobe

Cerebral lobe dedicated primarily to vision.

Dura Mater

The outermost layer of the meninges, positioned on top and closest to the skull.

Pia Mater

The deepest layer of the meninges surrounding the brain.

Epidural Bleed

Bleeding located above the dura mater, usually caused by a skull fracture that tears a blood vessel.

Subdural Bleed

Bleeding located below the dura mater, usually resulting from a head injury.

Open Brain Injury

A traumatic brain injury involving penetration of the skull (e.g., from a gunshot wound or sharp object), resulting mostly in focal damage limited to the penetrated area.

Closed Head Injury

A head injury caused by falls, hits, contact, or whiplash without skull penetration, where axons are stretched, sheared, or torn, causing broad focal and diffuse damage.

Mild TBI (Concussion)

A traumatic brain injury characterized by lesser levels of brain damage, $0\text{--}20\text{ mins}$ of loss of consciousness (LOC), and a Glasgow Coma Scale (GCS) score of $13\text{--}15$.

Moderate TBI

A traumatic brain injury marked by a loss of consciousness lasting between $20\text{ mins}$ and $6\text{ hours}$, and a Glasgow Coma Scale (GCS) score of $9\text{--}12$.

Severe TBI

A traumatic brain injury characterized by a loss of consciousness greater than $6\text{ hrs}$ and a Glasgow Coma Scale (GCS) score of $3\text{--}8$.

Second Impact Syndrome

A serious condition resulting from repeated head injury before a prior injury has healed, carrying a fatality rate of $50\%$.

Coup Injury

Brain damage occurring directly at the initial site of impact in an acceleration/deceleration event.

Contrecoup Injury

Brain damage occurring at the site of secondary impact, opposite or away from the initial impact point.

SCAT 5

Sideline Concussion Assessment Tool (5th edition), a standardized evaluation method used to assess concussions.

Photophobia

Abnormal sensitivity to light, commonly presenting as a symptom of a concussion.

Nystagmus

Involuntary, rapid rhythmic oscillation of the eyes that can appear as a clinical sign of concussion.

Retrograde Amnesia

The loss of memory for events occurring before the trauma; inability to remember events from the past.

Anterograde Amnesia

The inability to form new memories following an injury.

Chronic Traumatic Encephalopathy (CTE)

A progressive degenerative brain disease similar to Alzheimer's caused by abnormal protein buildup in the brain, linked to repeated concussions or sub-concussive hits.

Raccoon Eyes

Bruising around the eyes indicative of a skull fracture.

Battle's Sign

Bruising behind the ear that serves as a clinical sign of a skull fracture.

Halo Sign

A ring-like separation of blood and cerebrospinal fluid (CSF) draining from the nose or ear onto gauze, signaling a skull fracture.

Malocclusion

A condition in which the teeth do not line up properly, characteristic of temporomandibular joint (TMJ) injury or mandibular fracture.

(+) Tongue Blade Test

A clinical examination finding where an athlete cannot bite down firmly on a tongue blade, indicative of a mandible fracture.