Unit 6 - Spine/ External + Internal brain Flashcards
What 2 types of joints are shown here between 2 vertebrae?
What key structures are involved in both joints?
- Symphysis cartillagenous joint
Identify the 5 ligaments shown. What is their function?
What core ligament runs from the cranium to C7? What is its function?
- Nuchal
> Triangular void
> Prevents hyeprflexion of head
What is the spinal cord arterial and venous drainage?
What is the clinical significance of the venous drainage of the vertebral column?
- Internal vertebral venous plexus has NO valves
> Spread of cancer
How do the anterior spinal and posterior spinal arteries come about?
Label the layers surrounding the spinal cord.
At what vertebral level do the coverings of the spinal cord terminate?
Define primary and secondary curvature.
What other names can they be known as?
Which vertebrae are primary and secondary?
Primary = Kyphosis = Thoracic + Sacrum + Cocygeal
> Form during foetal development
Secondary = Lordosis = Cervical + Lumbar
> Form after birth
What are the 3 main pathologies of the spine?
How are vertebral arch and body connected?
2 pedicles extend from the side of vertebral body to join the body to arch.
Which meningeal space is an epidural administered?
> Above dura mater + below bone of vertebral column/skull
- Filled with fluid and surrounds spinal arch > stops pain signals travelling from spine to brain
Identify the bones of the neurocranium.
What muscle overlays the cranium?
- Occipital - frontalis muscle
Label the neurocranium.
What type of bones are these? How do they articulate with each other?
- Flat + Irregular > Via fibrous joint more specifically cranial suture
What is the pterion and why is it clinically significant?
- Weakest part of the skull
> Union of 4 bones
>Superior to : Zygomatic arch
> Posterior to Frontozygomatic arch
*Fracture = rip Middle meningeal artery > cause extradural haemorrhage leading to raise in inter cranial pressure.
- MMA comes out from foramen spinosum
What are the layers of the scalp from superficial to deep? What type of skin is present?
1- Thin skin , hair bearing
2- Connective tissue
3- Aponeurosis
4- Loose areolar connective tissue
5- Periosteum/pericranium
Label the meningeal layers in the cranium. (*change the layers of dura mater they are opposite)
- Only meningeal layer continues onto spine
How is cerebral spinal fluid cleared from the subarachnoid space?
- Diffusing through the walls of arachnoid granulation
- Valvular mechanism = CSF > bloodstream without back flow
Where do blood vessels supplying the meninges run > What type of haemorrhage would this cause?
- MMA enters foramen spinous and runs between dura and skull > epidural haematoma
Identify the lobes of the brain.
What type of neurone is found in the pyramids?
- Multipolar
- Cell body is triangular
- lots of dendrites
Label the main dural venous sinus.
How does venous drainage relate to meninges?
- Lies between periosteal dura and meningeal dura
Label the following dural folds.
Label the gross structure of the cerebellum. What is its function?
1- Balance
2- Muscle coordination
3- Muscle tone and posture
Nuclei = grey matter
What is the function of the brainstem?
-Breathing
-HR
-Reflexes
-Autonomic function
How does the brainstem communicate with:
Cerebrum
Cerebellum
Spinal cord
Cerebrum: Midbrain
Cerebellum: Cerebellar peduncles
Spinal cord: Medulla oblongata
How does brainstem leave skull?
- Foramen magnum
> In posterior cranial fossa
Label the sutures of the skull.
Why are fontanelle present? When do they go?
- Allow brain volume to increase
- Stretching and deformation of neuro cranium during birth and later on as brain expands faster than surrounding skull can grow.
Anterior cranial fossa:
1- What attaches to crista Galli?
2- What lies inferior to anterior cranial fossa?
3- What lobe sits in anterior cranial fossa?
1- Falx cerebri
2- Orbit
3- Frontal
Medial cranial fossa:
1- What structure holds the pituitary Gland?
2- What are the boundaries of medial cranial fossa?
3- What lobe sits in medial cranial fossa?
Label the foramen and what is inside?
1- Sella turica
2- Sphenoid ridge + Sphenoid wing
3- Temporal
Which grooves are associated with Forman spinous? What is their clinical relevance?
-Middle meningeal artery groove
> Puncture/fracture = rip artery and allow blood to accumulate in dura mater > extradural haemorrhage
Posterior cranial fossa:
1- What lobes sit in this fossa?
2- What is contained on the inside of jugular Foramen
3- What is contained inside of foramen magnum
> Crebellum + Occipital lobe
What do the following meningeal layers separate?
What are their attachments?
1- Falx cerebri
2- Tentorium cerebelli
3- Falx cerebelli
1- Falx cerebri : 2 Cerebral hemispheres / houses dural venous sinuses
> Anteriorly = Crista Galli
> Posteriorly = Internal occipital protuberance
2- Tentorium cerebelli : Cerebral hemisphere from cerebellum
> Anteriorly : Anterior clinoid process
> Posteriorly : Internal occipital protuberance + Transverse sinus
3- Falx cerebelli : 2 hemispheres of cerebellum
> Anteriorly : Between partially separated cerebellar hemispheres
> Posteriorly : Midline to internal occipital crest of occipital bone
Compare the location of the arteries supplying the brain and meninges.
Meninges = Middle meningeal artery (branch of maxillary , branch of external carotid)
- Enters formane spinisum and runs between dura and skull > epidural
Brain = Subarachnoid space
Label the foramen.
Familiarise with this image.
Label the lateral view of the brain
Label the ventricular system.
1 -Where is CSF produced?
2- Approx how much CSF in adult?
3- If their is blockage in ventricular system what pathology could arise?
4- What separates right and left lateral ventricle
- Choroid plexus
- 90-200ml
- Hydrocephalus > ventricles enlarge and put pressure on the brain
- Septum pellusidum (fornix > lateral edge )
What is the function of CSF?
- Provides mechanical support
- Supplies a route for metabolites to enter and leave neurons
- Allows circulation of neurotransmitters
What are the 3 routes in which CSF can leave and where to?
> 2 Lateral foramen = Laterally to subarachnoid
1 Median foramen = Medially to subarachnoid
Central canal to dural venous sinuses
1 - Which part of ventricular system does the thalamus form the wall to?
2 - What is the function of the thalamus? Is it composed of grey or white matter?
1- Lateral wall of 3rd ventricle
2-
>Transmit general and special sensory information to sensory regions of cortex
>Interact with the motor cortex and the limbic system (emotion/memory) > Relay system
GREY MATTER = CELL BODIES
Saggital view of Basal ganglia.
What is the striatum?
Caudate nucleus and Putamen
Label the parts of the brain including basal ganglia?
What is the function of basal ganglia?
- Production of movement > Facilitate or suppress movement
What are 2 examples of basal ganglia disorders?
1- Parkinsons disease = HypOkinetic disorder
2- Huntingtons disease = HypERkinestic disorder
Label the saggittal brain.
What is the function of the following:
Corpus callosum
Cingulate gyrus
Thalamus
Hypothalamus
Fornix
Midbrain
PONS
Medulla
Superior and Inferior colliculi
Corpus callosum: Communication between hemispheres of brain (Commissural fibres
Cingulate gyrus: Regulate emotions and pain
Thalamus: Relay system
Hypothalamus: Homeostasis
Fornix: connecting pathway between hippocampus and mammillary body
Midbrain: vision, hearing, motor control, sleep/wake, arousal (alertness), and temperature regulation,
PONS: unconscious processes and jobs, such as your sleep-wake cycle and breathing.
Medulla: Controls your heart rate, breathing, blood pressure and more.
Superior and Inferior colliculi : The superior colliculi play an important role in the visual pathway, while the inferior colliculi are important in the auditory pathway
The cortex forms Gyri ad Sulci. What are these?
Gyrus: Ridge of cortex
Sulcus: Depression surrounding gyrus
What function are frontal lobes associated with?
Higher cognitive functioning
- Judgement/ Foresight/ acceptable social behaviour
Primary sensory and motor areas are surrounded by what?
Association areas
- Primary sensory areas are surrounded by a larger zone of association cortex > interprets incoming signal
- Primary motor areas are also surrounded by association areas > involved in planning movements
The frontal lobe contains Pre-central gyrus what is this?
What is the result to a lesion of this area?
- Primary motor cortex
- Responsible for contraction of muscles on the contralateral side of the body
- Somatotopic organisation- Homunculus
> Paralysis in affected part of body (contralateral)
What is frontal lobe motor innervation?
- Supplementary motor cortex lies medially
- Pre-motor cortex lies anteriorly
- Plan and programme skilled motor activities to direct primary motor area to execute movement
The parietal lobe contains Post- central gyrus what is this?
What is the result to a lesion to this area?
- Primary somatosensory cortex
- Receives genera lsomatic sensory information
- Somato sensory association area lies posterior to the primary somato sensory area
> Agnosia , inability to understand significance of sensory info
What is the function of the Occipital lobe?
Where does the primary visual cortex lie?
What surrounds the primary visual cortex?
Vision
* Primary visual cortex lies in calcarine fissure (occipital lobe)
* Visual association area surrounds primary visual cortex
What is temporal lobe function?
Where foes primary auditory cortex lie?
What surrounds primary auditory cortex?
- Hearing
- Primary auditory cortex within temporal lobe
- Auditory association area surrounds primary auditory cortex
Where is Brocas and Wernickes area found?
What is their function?
What is the function of Insula?
> Function largely unknown
* 4 key areas of involvement
1- Sensorimotor region
* Particularly visceral processing and autonomic functions
* Somatic
* Auditory
2- Olfacto-gustatory region
3- Socio-emotional region
4- Cognitive region
* Attention processing – detecting novel stimuli across sensory modalities
Label the cerebrum functional overview.
What are the 3 fibre groups?
1- Association fibres: Links different parts of cortex within 1 hemisphere.
> Short: within 1 lobe
> Long: between lobes
2- Commissural fibres: Link 2 cerebral hemispheres across the midline .. Corpus callosum
3- Projection fibres: Link the cerebral cortex with the brainstem and spinal cord … Internal capsule
