Brain, Neck, and Spine Anatomy and Injuries

Flashcards covering brain and spinal anatomy, cranial nerves, perfusion pressure formulas, and various types of trauma and syndromes based on the lecture transcript.

Cerebrum

The largest part of the nervous system, divided into lobes including frontal, occipital, temporal, and parietal.

Frontal lobe

Responsible for personality, voluntary motor function, and problem-solving.

Occipital lobe

Responsible for vision, color, and depth perception.

Temporal lobe

Responsible for long-term memory, hearing, speech, taste, and smell.

Parietal lobe

Responsible for motor, sensory, memory, perception, and sensation.

Falx cerebri

Extends into the cranial cavity, dividing the right and left hemispheres.

Tentorium cerebelli

Divides the cerebrum and the cerebellum.

Cranial nerve III (oculomotor nerve)

Travels along the tentorium; increased intracranial pressure (ICP) puts pressure on this nerve, causing pupils to dilate on the affected side.

Hypothalamus

Located in the midbrain; controls endocrine function, vomiting reflex, thirst, kidney function, temperature, and emotions.

Thalamus

Plays a major role in the ascending reticular activating system to maintain consciousness.

Pons

Lays on top of the medulla oblongata and plays a role in sleep.

Medulla oblongata

Contains the respiratory center (rate, depth, rhythm), cardiac center (rate and strength of contraction), and vasomotor center.

Ataxia

Uncoordinated muscle movements and imbalance caused by damage to the cerebellum.

Circle of Willis

Formed at the base of the skull when 4 arteries join together; it becomes the basilar artery.

Blood-Brain Barrier

Thicker and less permeable central nervous system capillaries that inhibit interstitial flow of proteins from entering.

Cerebral Perfusion Pressure (CPP)

Pressure needed to move blood through cerebral circulation; calculated as $CPP = MAP - ICP$.

Monroe-Kellie Doctrine

States that intracranial volume is fixed; any change in brain, CSF, or blood volume impacts intracranial pressure.

Ascending Reticular Activating System

Responsible for the sleep-wake cycle and regulates ventilatory rate, heart rate, and peripheral vascular resistance.

Carotid Sinuses

Contain baroreceptors responsible for monitoring blood pressure.

Carotid Bodies

Contain chemoreceptors that monitor blood pH, oxygen, and carbon dioxide levels.

Vagus Nerve (CN X)

Involved in parasympathetic activities including speech, cardiac, respiratory, and swallowing.

Atlas (C-1)

Supports the head and allows for forward and backward movement, but not side-to-side movement.

Axis (C-2)

Pivot point that allows for side-to-side movement of the head.

Conus medullaris

The point where the spinal cord ends, typically at $L-1$ or $L-2$.

Cauda equina

Formed by spinal nerves from $L-2$ through $S-1$.

Babinski sign

Fanning of the toes and dorsiflexion of the big toe when stroking the bottom of the foot, indicating injury to descending tracts.

Dermatomes

Areas of sensation on the skin related to the specific spinal nerves that control them.

Phrenic nerve

Originates between $C2 - C5$ and innervates the diaphragm; damage above $C2$ results in the inability to breathe.

Epistaxis

A nosebleed, classified as anterior (involving Kieselbach's plexus) or posterior (severe, blood goes down the throat).

Hyphema

A collection of blood in the anterior chamber in front of the iris and pupil.

Retinal detachment

Condition where the retina separates from the posterior wall; patients report a dark curtain blocking their view.

Le Fort III Fracture

A facial fracture involving the maxilla, nasal, and zygomatic bones.

Epidural hemorrhage

Bleeding between the dura mater and skull, typically involving the middle meningeal artery; often features a "lucid period."

Diffuse Axonal Injury (DAI)

Nerve damage caused by stretching, shearing, and tearing forces most commonly from rapid acceleration-deceleration forces.

Cushing's Triad

A sign of increased ICP consisting of systolic hypertension (wide pulse pressure), bradycardia, and irregular respirations.

Decorticate posturing

Abnormal posturing where the arms are flexed inwards towards the core.

Decerebrate posturing

Abnormal posturing where the arms are extended, indicating middle brainstem compression.

Neurogenic shock

Condition where the brain cannot control autonomic functions; results in hypotension, bradycardia, and skin that is warm and dry below the injury.

Autonomic Hyperreflexia Syndrome

Associated with injuries at or above $T-5$, presenting with severe hypertension, bradycardia, severe headache, and blurry vision.

SCIWORA

Spinal Cord Injury Without Radiographic Abnormality; physical findings of injury exist but imaging (X-ray, CT, MRI) is normal.

Anterior Cord Syndrome

Often caused by flexion-extension injury causing loss of motor function and sensation to pain and light touch.

Central Cord Syndrome

Often caused by hyperextension of the cervical spine; results in upper extremity motor weakness and bladder incontinence while lower extremity strength remains normal.

Brown-Sequard Syndrome

Involves one side of the spinal cord (hemi-transection), causing ipsilateral sensory and motor loss and contralateral pain and temperature sensation loss.