NeuroAnatomy Flashcards
- Ventral –
- Dorsal –
- Cranial –
- Caudal –
- Rostral –
- Ventral – ‘front’
- Dorsal – ‘back’
- Cranial – ‘towards the head’
- Caudal – ‘towards the tail’
- Rostral – ‘towards the beak’
what are the two divisions of the forebrain?
telencephalon = cerebrum
diencephalon
what are the two divisions of the hindbrain?
Metecephalon = pons + cerebellum
Myelenceohalon = medulla oblongata
name all the embryobic divisions of the brain.
what is white matter?
why is it white?
nerve cell axons. They appear white due to the presence of myelin sheaths wrapped around the axons which speed up conduction.
what is grey matter?
primarily nerve cell bodies, including their nuclei, but also consists of other nervous system cells including astrocytes, oligodendrocytes or unmyelinated axons.
in the cerebrum, where is most of the grey matter located?
Cerebrum:
- outer = grey
- inner = white
in the spinal chord where is most of the grey matter located?
Spinal Chord
- outer = white tracts
- inner = H-shaped grey centre
what is the cortex of the brain?
the outer part of the cerebrum and cerebellum. Mainly grey matter.
what does the term nucleus refer to in neuroanatomy?
what colour are do they appear and where are they found?
groups of functionally similar or
anatomically related nerve cells
appear grey in large groups
found deep in brain (therefore grey not just on surface)
what is a tract?
a pathway of nerve fibres
no synapses in b
A tract may include a single group of nerve fibres with
no synapses in between the start and end of the tract, or it may include two or three
nerve fibres which synapse along the tract to pass information along.
what is a fossa?
indentation / shallow depression
what is a foramen?
opening/hole/passsage
what is the function of the frontal lobe?
- primary motor cortex
- planning and executing concious movement
- prefrontal cortex = behaviour, personality, decision making
what is the function of the temporal lobe?
- primary auditoy cortex
- hippo campus = memory formation
what is the function of the parietal lobes?
- primary somatosensory cortex
= process sensory information
What is the function of the occiptal lobe?
- primary visual cortex
what is the function of the cerebellum?
posture, balance, fine movement correction
what is the function of the brainstem?
connects the rest of the brain to the spinal cord. It contains the nuclei of the cranial nerves and contains vital centres for regulating breathing and cardiovascular
function.
what is a gyri?
bulge/crest/fold
what is a sulci?
groove/furrow
what does the central sulcus separate?
the frontal and parietal lobes
what does the lateral sulcus separate?
temporal lobe from the frontal and parietal lobe
what three components make up the brainstem?
midbrain, pons and medulla
what would you find if you teased the lateral sulcus appart?
the insula and opercula
* Insula – this is a part of the cerebral cortex that can only be seen by opening the lateral sulcus in this way. In some resources, it is considered to be a fifth lobe.
* Opercula – this term means ‘lid’ or ‘cover’. It refers to the parts of the frontal, parietal
and temporal lobes that cover the insula like lips around a mouth.
name the three sulcu/ fissures of the brain
Longitudinal fissure (left- right)
Central sulcus (frontal- parietal)
Lateral sulcus (Temporal- frontal parietal)
what would you find on separating the longitudinal fissure?
Corpus callosum – this is a large bundle of white matter (axons) that connects the two
hemispheres.
what are the olfactory tracts?
these are nerve fibres carrying information about smell from the nasal
cavity. They run along the inferior surface of the frontal lobes on both sides.
what are the optic nerves?
these nerves carry visual information from the retinas of the eyes. They’re
also seen on the inferior surface of the frontal lobe and pass posteriorly and medially, to
a point where they partly cross over each other (the optic chiasm).
what are the mammillary bodies?
these rounded structures are found just behind the optic chiasm and pituitary gland. They are part of the diencephalon.
where is the hypothalamus anatomically?
this is part of the diencephalon and is only just visible behind the optic chiasm. The mammillary bodies are located on its most inferior surface.
what are the crus cerebri?
this term means ‘feet of the brain’. They are pillars of white matter next to
the mammillary bodies that connect the rest of the brain to the brainstem. They form
part of the cerebral peduncles which are part of the midbrain.
what is the interpeduncular fossa?
this is the name of the fossa between the cerebral peduncles. It may have a layer of arachnoid mater overlying it on some brain specimens.
Where is the primary motor cortex?
posterior frontal lobe
which part of the brain is repsonsible for planning movements?
premotor cortex in frontal lobe
which are of brain is responsible for personality, behaviour, problem solving, impulse control and inhibition, and social
and sexual behaviour
prefrontal cortex in frontal lobe
where is brocas are found and what does it do?
the inferior frontal lobe of the dominant
hemisphere (normally the left) and is important for spoken language production.
where is wernickes are found and what does it do?
the most superior and posterior part of the dominant temporal lobe. It is important in understanding and coordinating spoken language.
what is the lymbic system made up from and what does it do?
hippocampus, amygdala, cortex and diecephalon.
As a group, they are involved in emotion, memory and behaviour. It has influence over the endocrine functions of the body and parts of it are specifically related to the
sensations of fear, pleasure and rewarding behaviours.
where is the amygalda found and what is it responsible for?
located deep within the temporal lobe, and it has a role in the perception of fear
in a homonculus, where are the face and mouth represented, where are the upper limb represented, and where are the lower limb represneted?
lateral = face and mouth
medial = feet
superior = upper limb
what are the two layers of the dura mater?
endosteal layer (outer)
meningeal layer (inner)
The inner meningeal layer completely envelops the brain and spinal cord. The
meningeal layer peels away from the endosteal layer in certain places and folds down
into the brain to form a double layer of dura that separates certain parts of the brain.
what is the falx cerebri?
is a double layer of folded dura lying in the longitudinal fissure
that separates the two cerebral hemispheres.
what separates the occipital lobe from the cerebellum?
tentorium cerebelli
what separates the two lobes of the cerebellum?
falx cerebelli
how are the dural venuous sinuses formed?
the outer endosteal and inner meningeal layer of the dura breifly pull apart from eachother, forming small channels filled with venous blood.
not shown = cavernous sinus
these ‘cave-like’ sinuses are found anteriorly, either side of the sella
turcica of the sphenoid bone. The internal carotid artery passes through it, along with
some important nerves.
where is cerebrospinal fluid made?
Choroid plexus of later third and fourth ventricles
what is the blood-brain barrier made from?
layer of pia and endotherlial cells
what features of the blood-brain barrier allow it to limit the passage of harmful substances?
- endothelial cells
- basement membran not fenestrates
- pericytes
- astrocytes
- The endothelial cells are tightly bonded together to prevent molecules passing between
them. - The basement membrane of the capillaries in the brain and spinal cord lacks fenestrations (small holes) that are found elsewhere in the body.
- Further specialised cells known as ‘pericytes’ wrap around the endothelial cells to regulate blood flow and permeability.
- CNS cells called ‘astrocytes’ have specialised projections called ‘end feet’ that further wrap around the capillaries to restrict flow of certain molecules.
label the pathologies
left = extradural heamorrhage
middle = subdural haematoma
right = subarachnoid haemorrhage
extradural = endosteal layer of the dura is tightly stuck to the inside of the skull, meaning blood
trapped outside of it bulges inwards and cannot spread around the side of the brain.
subdural = Unlike in the extradural space, the arachnoid and dura are not adherent to each other, so blood can easily spread around the sides of the brain causing the crescent appearance
subarachnoid = Blood leaks into the subarachnoid cisterns, mixing with the CSF, sometimes causing a white star-shaped pattern on a CT scan.
arterial blood supply to the brain comes from which arteries (pairs)?
what do they form together?
Internal carotid arteries (80%)
vertebral arteries (20% posterior)
= circle of willis
label the circle of willis
what does the anterior cerebral artery (ACA) supply?
medial aspects of the frontal and parietal lobes, and a strip of cortex on the superior aspect. Plus anterior diencephalon
- motor and somatosensory cortex of lower limbs.
what does the middle cerebral artery MCA supply?
vast majority of the lateral aspects and deep parts of the hemispheres. Plus some diencephalon
- motor and somatosensory of face arms trunk
- internal capsule (transmits all fibres to and from corticles)
What does the Posterior cerebral artery (PCA) supply?
the occipital lobe which contains the visual cortex, but also a small portion of the inferior temporal lobe.
What does the Basilar artery supply?
Pons
- As the pons forms part of the pathway of between
the brain and spinal cord, disruption of the basilar artery can potentially threaten the function of all ascending and descending fibres including all motor control and sensation from the neck down.
what do the cerebellar arteries (AICA, PICA SCA) supply?
Cerebellum
(plus parts of brainstem with basilar)
what makes up the anterior circulation of the brain?
ACA and MCA
what forms the posterior circulation of the brain?
PCA, Basilar and Cerebellar
what is a stroke?
A stroke is an interruption to the blood supply of part of the brain leading to a neurological
deficit that lasts longer than 24 hours.
ischeamic/haemorrhagic
in the brain, venous blood is drained from [a] into [b] before passing into the veins to be returned to the heart
The venous drainage of the brain is unique in that venous blood is drained from smaller cerebral
veins into large dural venous sinuses before passing back into veins to be returned to the heart.
- Cerebral venous blood first drains into [a], which are located deep within the brain tissue.
- The [a] then drain into larger [b] which can be seen on the surface of the brain.
- The [b] then drain into the [c].
- The [c] can drain the blood into extracranial veins via two routes:
o The [d] become the [e] as they exit the skull.
o [f] cross the endosteal layer of dura and drain the venous blood into the bones of the skull.
- Cerebral venous blood first drains into internal cerebral veins, which are located deep
within the brain tissue. - The internal cerebral veins then drain into larger external cerebral veins which can be
seen on the surface of the brain. - The external cerebral veins then drain into the dural venous sinuses.
o These are discussed in the meninges section above, under Dura Mater. - The dural venous sinuses can drain the blood into extracranial veins via two routes:
o The sigmoid sinuses become the internal jugular veins as they exit the skull.
o Emissary veins cross the endosteal layer of dura and drain the venous blood into
the bones of the skull
what passes through the cavermous sinus (behind orbit)
why is this clinically relevant?
internal carotid, (III) (IV) (V1) (V2) (VI)
The cavernous sinus is the only site in the body where an artery (internal carotid) passes completely through a venous structure.
Venous blood draining from the face can potentially drain into the cavernous sinus, thereby providing a connection for superficial infection of the face to reach intracranial structures. Infection in the cavernous sinus can lead to meningitis or thrombosis. A thrombosis here will cause an increase
in pressure and compress these nerves leading to problems with eye movements and sensation over the face.
what are the ventricles of the brain?
There are central cavities within the brain that are filled with cerebrospinal fluid (CSF)
They are continuous with the subarachnoid space meaning the CSF can surround the brain and spinal cord. In this way, the
brain is submerged in a thin layer of CSF which provides a degree of physical protection, and
mechanism for transfer of certain substances in and out of the brain tissue.
where is CSF produced?
lateral ventricles by choroid plexus
how does CSF flow from the lateral ventricles into the third ventricle?
via the interventricular foramen
what connects the third and fourth ventricle?
cerebral aqueduct
how does CSF leave the ventricular system?
- Inferiorly via central canal to fill subarachnoid space around spinal chord
- Posteriorly via apperture of magendie and lateral apertures of Luschka to enter subarachnoid space
how is CSF recycled back into the bloodstream?
arachnoid granulations
- Using your knowledge of the functional areas of the brain and their blood supply, what
might be the likely consequence of a blockage of the following arteries?
a. Left middle cerebral artery.
b. Right posterior cerebral artery.
c. Basilar artery.
a - upper limb, facial weakness
b - left visual field defect
and cerebellar disfunction
c- numerous cranial nerves, ascending descending - locked in syndrome
Which lobes of the brain are located superior, inferior and deep to the lateral sulcus?
superior = parietal and frontal
inferior = temporal
deep = insula
What is the name of the sheet of fibrous material that divides the two hemispheres of the brain in the longitudinal fissure? What is this tissue part of?
falx cerebri
made of two layers of dura mater
What are the names of the large vessels that drain venous blood from the brain to the internal jugular veins?
dural venous sinouses.
(sigmoid –> internal jugular)
- Between which two layers of the meninges would you find CSF?
arachnoid and pia mater (subarachnoid space)
What are the three routes that CSF can take out of the fourth ventricle?
central canal, median aperture, lateral aperture.
Where is CSF produced and where is it reabsorbed?
choroid plexus in lateral ventricles.
reabsorbed by arachnoid granulations
Which arteries supply the following areas of the brain?
a. Wernicke’s area.
b. Broca’s area.
c. Primary auditory cortex.
d. Part of the somatosensory cortex receiving sensory information from the arms
and face.
e. Part of the motor cortex that controls the feet and toes.
a. MCA
b. MCA
c. MCA
d. MCA
e. ACA
What layers of tissue must be penetrated during surgery to reach the surface of the brain
from outside the head?
skin, fascia, aponeurosis of scalp muscles, fascia, periosteum, skull, dura mater, arachnoid materm pia mater
What type of bleed between the layers of the meninges is likely in the following cases?
a. Young adult patient who suffers a lateral head injury after falling off a bicycle without a helmet. They remain conscious for 12 hours after the injury, before becoming profoundly unconscious.
Extradural heamorrage
What type of bleed between the layers of the meninges is likely in the following cases?
b. Elderly patient with a history of heavy alcohol use who stumbles at home and bangs their head. They retain consciousness, but the family notices they are
becoming gradually more confused over the next two weeks.
subdural heamatoma
What type of bleed between the layers of the meninges is likely in the following cases?
c. A middle-aged patient with a known cerebral aneurysm who suffers a very severe,
sudden-onset, ‘worst-ever’ headache and becomes photophobic with vomiting
and drowsiness.
Subarachnoid haemorrhage
The base of the skull is formed from several individual bones joined by fibrous joints known as ?
sutures
label the three cranial fossa of th ebase of the skull
What passes thorugh the hols of the cribiform plat of the ethmoid bone?
olfactory nerves
what three bones make up the anterior cranial fossa?
Frontal bone - (orbital part)
Ethmoid bone - (the cribiform plate and cristal galli)
Sphenoid bone - (the lesser wings of)
what two bones make up the middle cranial fossa?
Temporal bone - Petrous and squamous parts
Sphenoid bone - Greater wing and body
- pituitary fossa / sella tucica located in middle cranial fossa
Label the foramina of the cranial fossa.
What does the optic canal transmit?
the optic nerve into the bony orbit.
what does the superior orbital fissure transmit?
transmits several nerves that provide motor innervation
(oculomotor, trochlear and abducens nerves) and sensation (ophthalmic branch of the trigeminal nerve) to the orbital region.
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whay does the foramen rotundum transmit?
the maxillary branch of the trigeminal nerve.
what does the foramen ovale transmit?
the mandibular branch of the trigeminal nerve.
what does the foramen lacerum transmit?
the internal carotid artery exits the carotid canal through this
foramen to enter the skull.
what does the foramen spinosum transmit?
middle meningeal artery
what makes up the posterior cranial fossa?
ocipital bone
petrous part of temporal bone
what does the internal auditory meautus transmit?
the vestibulocochlear and facial nerves into the
inner ear cavity.
what does the jugular foramen transmit?
the glossopharyngeal, vagus and accessory nerves, and the
internal jugular vein.
VAG
what does the hyposglossal canal transmit?
the hypoglossal nerve
what does the foramen magnum transmit?
central nervous system fibres to leave the skull and become the spinal cord.
what is the weakest part of the skull?
the Pterion - shallow depression where four bones (frontal, parietal, temporal, sphenoid) of the skull converge
-where the middle meningeal artery lies ∴ traumatic injusry here likely extradural haemorrhage
what bones make up the bony orbits?
the larger frontal, sphenoid, zygomatic and maxillary bones, and the smaller ethmoid and lacrimal bones.
what nerves run through the orbits?
II = vision
III IV XI = muscles
V (opthalmic division) = sensation to eye and forehead
- Elevation –
- Depression –
- Adduction –
- Abduction –
- Extorsion –
- Intorsion –
- Elevation – to look up.
- Depression – to look down.
- Adduction – to look medially.
- Abduction – to look laterally.
- Extorsion – to rotate the eye, so the top of the eye rotates laterally.
- Intorsion – to rotate the eye, so the top of the eye rotates medially.
Both eyes do not necessarily perform the same movement when you change where you look.
For example, to look to your left with both eyes, your left eye needs to abduct, but your right eye
will need to adduct. This is known as conjugate eye movements.
Muscle - nerve supply - action to eye - findings if non-functional
Muscle - nerve supply - action to eye - findings if non-functional
Muscle - nerve supply - action to eye - findings if non-functional
Muscle - nerve supply - action to eye - findings if non-functional
Muscle - nerve supply - action to eye - findings if non-functional
Muscle - nerve supply - action to eye - findings if non-functional
Which Extraocular muscles are supplied by CNXI, CNIV and CNIII?
Lateral Rectus = CN6
Superior Oblique = CN4
The rest = CN3
LR6SO4
label the seven extraorbital muscles
Superior view - so which one cant be seen?
Inferior Oblique underneath
label the extraocular muscles
what is the main function of the superior and inferior rectus?
what are their additional actions?
mainly: elevate and depress the eye.
additionally: intorsion and extorision = econdary effects caused by the angle at which these two muscles pull on the
eye.
When looking at the orbits from above, if you draw a line through the centre of both orbits (which represents the angle at which these muscles pull on the eye) you’ll notice these two lines are not parallel and they do not point directly forwards. They diverge off to each side. However, the eye is normally angled to point directly forwards. This means that when the superior or inferior recti act on the eye, they are not only pulling it upwards or downwards, but they are also causing it to intort or extort and adduct.
The [a] muscle originates at the back of the eye but passes through a fibrous sling called the [b], which is located in the [c] corner of the orbit. The muscle then inserts onto the top of the eye, so it’s action will pull the top of the eye medially,
causing it to rotate. The top of the eye rotating inwards is called [d].
The superior oblique muscle originates at the back of the eye but passes through a fibrous sling called the trochlea, which is located in the superior and medial corner of the orbit. The muscle then inserts onto the top of the eye, so it’s action will pull the top of the eye medially, causing it to rotate. The top of the eye rotating inwards is called intorsion.
The [a] muscle originates from the medial orbital wall and inserts on the bottom of the eye. Its action will pull the bottom of the eye medially, also causing it to rotate, but in
the opposite direction. With the top of the eye rotating outwards, this is called [b].
INferior oblique
extorsion
The reason that the eye needs the oblique muscles to be able to intort and extort is to counter the secondary effects of extorsion and intorsion caused by the [?] muscles respectively. This helps maintain steady vision when looking up or down.
inferior and superior recti
The eye is responsible for providing us with sight. As light enters the eye, it is focused to [a] onto the [b] where it is detected by specialised cells called [c]. These cells
generate nerve impulses which are transmitted along the [d] towards the [e] in the occipital lobe.
The eye is responsible for providing us with sight. As light enters the eye, it is focused to converge onto the retina where it is detected by specialised cells (rods and cones). These cells generate nerve impulses which are transmitted along the optic nerve and optic tracts towards the primary visual cortex in the occipital lobe.
To achieve good vision, the eye must be able to focus light to varying amounts depending on how far away the object is that is being visualised. This is called ?
accomidation
accomidation in the eye is acheived by adjusting ?
the thickness of the lens
thicker = greater refraction ∴ near sight
thinner = less refraction ∴ far sight
what muscles are responsible for adjusting thr thickness of the eye lens?
innervation?
ciliary muscles
Oculomotor nerve (CNIII).
Parasympathetic (Autonomic)
which muscle is responsible fot pupillary constriction?
innervation?
Constrictor Pupilae = circular muscle in iris
Oculomotor never (CNIII)
Parasympathetic (autonomic)
which muscle is responsible for dilating the pupils?
innervation?
dilator pupillae = radial muscle in iris
Sympathetic fibres from Sypathetic Chain (autonomic)
What are the afferent and efferent nerves of the pupillary light reflex?
afferent (sensory) = optic nerve
- information about light from retina to midbrain
⇩
> synapses with Edinger-Westphal nucleus<
⇩
efferent (motor) = oculomotor nerve
- initiates dilator/constrictor pupilae muscles
When a light is shone in one eye of a healthy patient, both pupils will constrict.
The constriction of the pupil which is having a light shone into it is called the [a], and the constriction of the other pupil is called the [b].
The reason that the other pupil constricts as well is because there is a connection between the right and left [c] such that if one side is activated, then both sides are activated.
When a light is shone in one eye of a healthy patient, both pupils will constrict.
The constriction of the pupil which is having a light shone into it is called the direct pupillary response, and the constriction of the other pupil is called the consensual pupillary response.
The reason that the other pupil constricts as well is because there is a connection between the right and left Edinger-Wesphal nuclei such that if one side is activated, then both sides are activated.
why does our nose run when we cry?
tears flow across the surface of the eye into the lacrimal ducts, then into the nasal cavity via the nasolacrimal duct.
Explain the clinical findings of oculomotor nerve palsy
Affected eye = down-and-out (depressed and abducted)
-This is because the lateral rectus and superior oblique muscles are unopposed so pull the eye into that position at rest.
Affected eye = pupil dilation
-loss of parasympathetic nerve supply to the constrictor pupillae, leaving dilator pupillae unopposed.
Affected eye - eyelid droop
- loss of motor nerve supply to levator palpebrae superioris, the eyelid will droop (ptosis)
Additionally, on asking the patient to look left and
right, the affected side will be unable to adduct.
What would the clinical finding be with Abducens nerve palsy?
affected eye unable to abducts
-lateral rectus muscle no longer working
-lateral rectus overpowered by medial rectus
stabismus/ “squint”
what are the two parts of the midbrain?
tectum (dorsal)
tegmentum (ventral)
123456 imprtant to know (and deduce others)
After exiting the skull, the facial nerve gives of a small branch which carries sensory information from the [a] and motor supply to [b]. The main body of the facial nerve then enters
the substance of the [c] (which it does not innervate), and within it, divides
into [d] branches which spread out across the face to supply the muscles of facial expression.
After exiting the skull, it gives of a small branch which carries sensory information from the ear and motor supply to some muscles of the scalp. The main body of the facial nerve then enters the substance of the parotid salivary gland (which it does not innervate), and within it, divides into five branches which spread out across the face to supply the muscles of facial expression.
Light is detected by the [a] within the eye and impulses are passed via the [b] then
[c]and finally the [d] before reaching the [e] in theoccipital lobe.
The fibres divide and cross over in a complex way.
[a] retina
[b] optic nerve
[c] optic tracts
[d] optic radiations
[e] primary visual cortex
each visual field is divided into:?
temporal (lateral) and nasal (medial) field
It is vital to understand that light entering from
the lateral half of our visual field is received by the medial (nasal) part of the retina, and vice
versa. So, the nasal retina provides our temporal visual field, and the temporal retina provides
our nasal visual field.
The visual information within the parietal radiations is received from the ?
and therefore constitures which field of vision?
The visual information within the parietal radiations is that which is received in the superior aspects of the retinas, and therefore constitutes the inferior fields of vision.
Conversely, the
information in the temporal radiation is from the inferior retinas, which is therefore from the
superior parts of our field of vision.
what would this be caused by?
damage to an optic nerve
what would this be caused by?
damage to optic chiasm (The fibres that cross at the optic chiasm are carrying visual
information from the nasal retinas, and therefore information about the temporal visual
fields.)
what would this be caused by?
damage to an optic tract
If left optic tract is damaged, information from the left temporal retina and right nasal retina is
lost, meaning the left nasal visual field and the right temporal visual field are lost. This would
mean the patient has lost the right side of their vision in both eyes, so would be termed a
right homonymous hemianopia.
what would thisbe caused by?
damage to either parietal or temporal optic radiation. (between the lateral geniculate nucleus)
If the left parietal optic radiation is
damaged, information from the left superior temporal retina and right superior nasal retina is lost, meaning the left inferior nasal visual field and the right inferior temporal visual field are
lost. This would mean the patient has lost the bottom-right corner of their vision in both eyes,
so would be termed a right inferior homonymous hemianopia.
Spinocerebellum:
anatomical part?
Primary INput?
Cerebella peduncle?
Function?
cerebrocerebellum.
anatomical part?
Primary INput?
Cerebella peduncle?
Function?
vestibulocerebellum.
anatomical part?
Primary INput?
Cerebella peduncle?
Function?
which nerve?
occulomotor
which nerve?
trigeminal
which nerve?
trigeminal
which nerve?
abducens
which nerve?
glossopharyngeal
which nerve?
hypoglossal
are autonomic nerves myelinated or unmyelinated?
myelinated preglangion
unmyelinated postganglion
what are the receptors of the sympathetic and parasymapthetic nervous system?
Sympathetic
- pregang = nicotinic
- postgang = Adrenergic
Parasympathetic
- pregang = nicotinic
- postgang = muscarinic
what are the distinct types of curvatures of the vertebral column?
cervical lordosis (inwards)
thoracic kyphosis (outwards)
lumbar lordosis
scoliosis = lateral curvature
where is the “atlas”?
C1 - artiulates directly with occipital bone of skull, allows us to nod our heads.
how does the axis differ from other vertebrae?
C2 - has a body that prodtrudes upwards = odontoid process = takes the place of the bodyof the atlas aboves it so that the atlas can spin around the axis.
atlanto-axial joint = pivot joint
describe the Vertebral body, spinous process and transverse processes of the Cervical Vertebrae (C3-C7)
Vertebral body - small
Spinous process = bifid (except C7)
Travsverse processes = contain transverse foramen
describe the Vertebral body, spinous process and transverse processes of the Thoracic Vertebrae
Vertebral body - medium, heart shaped
Spinous process - long, sharp, down-sloping
Transverse processes - contain articulation for the ribs
describe the Vertebral body, spinous process and transverse processes of the Lumbar Vertebrae
Vertebral body - very large
Spinous process - large, short, rectangular
Transverse processes - long, flat, directed laterally
what makes up the layers of a secondary cartilaginous joint, like that of the invertebral discs and vertebrae?
bone
hyaline cartilage
fibrocartilage
hyaline cartilage
bone
label the spinal ligaments of the vertebral column
What do the paraspinal muscles make up?
the erector spinae
what does this T2 weighted MRI show?
disc herniation - repetitive compression of the invertebral discs → weakining of annulus fibrosus→posterior herniation of nucleus palposus→narrowing intervertebral foramina→compress spinal nerve → neurological defecot/muscle weakness
what is the cauda equina?
“horses tail” all the spinal nerves that are yet to leave after the spinal chord terminates are given off all together.
where do the dorsal column medial lemniscus deccussate?
the Medulla.
after synapsing at thier nuclei in medulla.
deccussat and contine to thalamus contralaterally
where do the DCML tracts synapse?
- at the medulla - gracile and cuneate nuclei
- at the thalamus - conyinue to primart somatosensory cortex
where does the spinothalamic tract deccussate?
in the spinal cord. usually after travelling up one or two vertebral levels
where does the spinothalamic tract synapse?
- within dorsal horn
- in the thalamus - continue via intenal capsule via primary somatosensory cortex
where do the lateral corticospinal tracts deccussate?
the medulla
-at the level of the medullary pyramids - continue contralaterally in spinal cord
where do the lateral corticospinal tracts synapse?
- in the ventral horn
UMN →motor cortex → internal capsule → medulla DECCUSSATES → spinal cord → ventral horn SYNAPSE →LMN
What would the finding be is patient suffers damage to the right hand spinal cord?
Right: loss of DCML and Corticospinal
Left: loss of Spinothalmic
