Spinal Anatomy Flashcards
The notochord remains as what in the body?
Nucleus pulposus
The vertebral column develops from what embryologically?
Mesoderm
3 primary ossification centers of the vertebrae?
Centrum (for the body)
Right and left halves of the neural arch
What are the 5 secondary ossification centers of vertebrae?
Spinous process
Rt and Lt transverse processes
Upper and lower vertebral endplates
Shapes of the vertebral bodies for each section?
Cervical- Rectangular
Thoracic- Heart shaped
Lumbar- Kidney shaped
Orientation of the superior articular facets for each vertebral section?
Cervical- BUM
Thoracic- BUL
Lumbar- BM (Just backwards and medially)
The posterior longitudinal ligament continues as the ________ from C2 and above?
Tectorial membrane
The supraspinous ligament continues as the ________ from C7 and above?
Nuchal ligament
What is the job of the alar ligament?
Prevent axial rotation
The anulus fibrosus fibers are angled at ____ degrees to the vertical?
65 degrees
The anulus fibrosus is thickest in the ______ region and thinnest in the ______?
Lumbar
Thoracic, Respectively.
What part of the anulus fibrosus is innervated?
Outer 1/3
The intervertebral disc is nourished by ______ from the vertebral endplates?
diffusion (not well vascularized)
What does the intervertebral foramen all contain?
Spinal nerve, spinal nerve roots, dorsal root ganglion, spinal artery, veins, 2 to 4 sinuvertebral nerves, fat and transforaminal ligaments
The spinal canal is largest in what region?
Cervical
Why is the cervical region the most common site for cord compression?
The spinal cord is widest in this region (specifically C6)
The atlanto-occipital joint is classified as what?
Condylar (synovial)
The median atlanto-axial joint is classified as?
Pivot (synovial)
The lateral atlanto-axial joint is classified as?
Planar (synovial)
Zygapophyseal (facet) joints are classified as?
Planar (synovial)
50% of flexion and extension in the cervical spine occur at which joint?
Occiput-C1
50% of the rotation in the cervical spine occurs at which joint?
C1-C2 (Atlanto-axial)
What is the range of motion of the SI joint? And what axis does this occur about?
Nutation/counternutation
-Around an axis passing through S2
Innervation of the SI joint?
Superior gluteal nerve and branches from S1 S2
The costochondral joints are classified as what?
Synchondrosis (primary cartilaginous)
The manubriosternal joint is classified as what?
Symphysis (Secondary cartilaginous)
The superficial layer of back muscles is made up of what?
Trapezius and latissimus dorsi
The intermediate layer of back muscles is made up of what?
Levator scapulae, Rhomboid major and minor, Serratus posterior superior and inferior
The deep layer of back muscles is made up of what?
Splenius capitis, splenius cervicis, erector spinae, semispinalis capitis and cervicis, rotatores, interspinales, intertransversales, multifidus
The Multifidus muscles range from what vertebral levels?
Upper part of sacrum all the way to C2
What is the most medial of the lumbar back muscles?
Multifidus
The medial intertransverarii muscles are supplied by ________ and the lateral are supplied by _________?
Dorsal rami, ventral rami, respectively.
What is the main function of the small back muscles such as rotatores, interspinales and intertransversales?
mechanoreceptors (packed w/ muscle spindles?
What level of the spine does the cord end at?
L1/L2
What layer that covers the spinal cord has the dentate ligaments?
Pia mater
The posterior/dorsal columns carry what sensations?
Vibration, fine touch (2 point discrimination), and joint position sense (proprioception). These are known as the Gracilis and Cuneatus tracts
The lateral spinothalamic tract carries what sensations?
Pain and temperature
The ventral spinothalamic tract carries what sensations?
Crude touch and pressure
What is the only descending tract that isn’t motor in function?
Raphespinal (modulates nociception)
What is the job of the raphespinal tract?
Inhibits nociception by releasing serotonin and acts on the C fibers
Rexed lamina II in the grey matter is also called?
Substantia Gelatinosa (Involved w/ pain sensibility)
Substance P is found in high concentration in these laminae?
I & II
Lamina III & IV are often combined and called?
Nucleus proprius
Lamina VII contains the dorsal nucleus (Clarke’s column) and axons from here ascend the spinal cord and carry what?
Unconscious proprioception
The single anterior spinal artery supplies approximately how much of the spinal cord? (w/ all its branches)
Anterior 2/3
The 2 posterior spinal arteries supply how much of the cord?
Posterior 1/3
The Great Radicular artery (of Adamkiewicz) supplies which part of the spinal cord?
Lower 1/2 or 2/3 of the spinal cord
What type of neuroglia cells make CSF?
Ependymal cells
The blood supply for anterior circulation of the brain is supplied by?
Internal carotid arteries
The blood supply for posterior circulation of the brain is supplied by?
Vertebrobasilar system
The connections between the blood supply in the brain is called?
Circle of Willis
The basilar artery supplies which part of the brain?
Pons which contains nuclei for CN V, VI, VII, & VIII
What artery supplies the medulla which has nuclei for CN IX, X, XI, and XII?
Vertebral artery
Where is the primary olfactory cortex located? (Where CN I fibers end)
In the temporal lobe
The only sensory CN that is not linked directly with the thalamus?
Olfactory nerve (CN I)
CN III also carries parasympathetic fibers to what?
Circular iris muscle and ciliary body
What is the only CN that exits the brainstem dorsally?
Trochlear (CN IV)
Parasympathetic fibers do what to the pupil?
Constrict
The ophthalmic division of CN V gives off what branches?
NFL:
Nasociliary
Frontal
Lacrimal
The maxillary division of CN V gives off what branches?
PINZ Pharyngeal Infraorbital Nasopalatine Zygomatic
CN VII innervates what muscle in the middle ear?
Stapedius (nerve to the stapedius)
CN VII conveys taste via what nerve? To what nucleus?
Chorda tympani
Solitary tract nucleus
The primary auditory cortex is located where?
Middle portion of the superior temporal gyrus (Brodmann’s area 22)
CN IX (glossopharyngeal) contains motor fibers from the nucleus ______ to 1 muscle, which is?
Nucleus ambiguus
-Stylopharyngeus muscle
CN IX carries taste from the posterior 1/3 of the tongue to the nucleus ______?
Solitarius
What are the 3 CN’s that pass through the jugular foramen?
CN’s IX, X, and XI
CN X can go as far down as the?
Transverse colon in the abdomen
Which triangle of the neck does CN XI pass through?
Posterior cervical triangle
All of the intrinsic and extrinsic muscles of the tongue are supplied by CN XII except??
Palatoglossus (pharyngeal plexus of the vagus nerve)
Special Somatic Afferent (SSA) fibers are for which special senses?
Vision, hearing and balance
Special Visceral Afferents (SVA) fibers are for which special senses?
Taste
Smell
The caudate nucleus, putamen, and globus pallidus are collectively called the?
basal ganglia
The internal capsule is divided into what 3 parts?
Anterior limb
Genu
Posterior limb
The caudate nucleus and putamen can be collectively called?
Corpus striatum (they are separated by the anterior limb of the internal capsule though)
The left and right cerebellar hemispheres are joined centrally by the?
Vermis
What part of the vertebral artery is most prone to dissection?
3rd part (between C1 transverse foramen and foramen magnum)
The 2 vertebral arteries come together near the pons to form the?
Basilar artery
What produces CSF and where?
Choroid plexus in the lateral ventricles at a rate of 500 ml/day
Sometimes the superior sagittal and straight sinuses join to form the?
Confluence of sinuses
The sigmoid sinus passes through the jugular foramen and becomes?
Internal jugular vein
The anterior fontanelle should be closed by?
The first 18 months of life
The posterior fontanelle should be closed by?
The first 2-3 months of life
What is the highest point on the skull in the sagittal plane called?
Vertex
What are the 5 layers of the scalp?
Skin, Closed connective tissue, Aponeurosis, Loose connective tissue, and Pericranium (SCALP)
The periosteum is attached to the underlying bone by?
Sharpey’s fibers
What is the blood supply to the scalp?
External Carotid Artery
The muscles of facial expression are innervated by what branches from CN VII?
Temporal, Zygomatic, Buccal, Marginal mandibular, Cervical (Ten Zebras Broke My Car)
All of the muscles of the larynx are supplied by the recurrent laryngeal nerve of the vagus except?
Cricothyroid (superior laryngeal branch of CN X)
The cervical plexus is derived from the ventral rami of which nerves?
C1-C4
The ansa cervicalis is made up of which cervical nerves?
C1, C2, C3
What nerve supplies the diaphragm and from what levels?
Phrenic nerve
“C3, C4, C5 keep the diaphragm alive”
The axillary nerve (C5-6) supplies which muscles?
Deltoid and teres MINOR
Damage to what branch of the brachial plexus will result in “Winged scapula?”
Long thoracic nerve (C5-7)
Damage to C5 & C6 roots will result in?
Erb-Duchenne palsy
Damage to C8 and T1 roots will result in?
Klumpke’s palsy (Claw hand)
The Sciatic nerve (L4, L5, S1-3) supplies all of the skin below the knee except?
A thin strip along the medial aspect of the leg and foot which is supplied by the saphenous branch of the femoral nerve
Where does the sympathetic division of the autonomic nervous system originate?
Posterior nuclei in the hypothalamus
The main end organ neurotransmitter in the sympathetic system is what?
Norepinephrine (except the sweat glands- acetylcholine)
Cardiac plexuses are from what thoracic sympathetic level ganglia?
T1-T4
The greater splanchnic nerves are derived from what levels and go to what ganglion?
T5-T9 ganglia (to celiac ganglion)
The lesser splanchnic nerves are from what levels and go to what ganglion?
T10 & T11 (to superior mesenteric ganglion)
The least splanchnic nerves are from what level and go to what ganglion?
T12 (to aortico-renal ganglion)
The inferior hypogastric nerve is from what sympathetic levels?
L1 & L2
The parasympathetic division of the autonomic nervous system originates from where?
Anterior nuclei in the hypothalamus
Parasympathetic fibers are carried in what nerves?
CN III, VII, IX, X and S2-4
The main neurotransmitter for the parasympathetic system is what?
Acetylcholine
What are the tissues that have ONLY parasympathetic innervation?
Bronchial glands
What are the tissues that have ONLY sympathetic innervation?
Blood vessels, Arrector pili muscle, Adrenal Medulla, Sweat glands
BAAS
What does the Myenteric plexus of Auerbach do?
Regulates Motility of the muscularis externa in the intestine wall (M with M)
What does the Submucosal plexus of Meissner do?
Regulates the Secretion of intestinal glands (S with S)
What are the 3 types of autonomic mediated reflexes?
- Viscerovisceral
- Viscerosomatic
- Somatovisceral
What roots make up the Lesser Occipital nerve?
C2, C3
This nerve is sensory to the posterolateral neck
lesser occipital
what roots make up the greater auricular nerve
C2, C3
what roots make up the transverse cervical nerve?
C2, C3
What roots make up the supraclavicular nerve?
C3, C4
what roots make up the nasa cervicalis (superior and inferior roots)?
C1-C4
What roods make up the segmental branches of the cervical plexus?
C1-C5
What roots make up the phrenic nerve?
C3, C4, C5
“keep the diaphragm alive”
What is sensory to the ear and parotid gland?
greater auricular
what is sensory to the anterior and lateral neck?
transverse cervical
what is sensory to the shoulder and anterior chest?
supraclavicular
what is motor to the geniohyoid and infra hyoid muscles of the neck?
ansa cervicalis
what is motor to the neck and scalenes, levator, trapezius, and SCM?
segmental branches
what is motor to the diaphragm?
phrenic
what roots make up the femoral nerve?
L2-L4
what roots make up the obturator nerve?
L2-L4
what roots make up the lateral femoral cutaneous nerve?
L2, L3
what roots make up the iliohypogastric?
L1
what roots make up the ilioinguinal?
L1
What roots make up the genitofemoral?
L1, L2
what nerve is sensory to the thigh, leg, foot, hip and knee joints and motor to the anterior thigh, psoas, pectinous, and iliacus?
Femoral
what nerve is sensory to the medial thigh and hip joint and motor to the adductors, gracilis, and obturator externus?
obturator
what nerve is sensory to the lateral thigh, and branches to the peritoneum?
Lateral Femoral Cutaneous
what nerve is sensory to the lower abdomen, lower back and hip, anterolateral abdominal wall and pubic region?
iliohypogastric
what nerve is sensory to eh scrotum, labia ,thigh and cremasterics?
genitofemoral
what nerve roots make up the sciatic nerve?
L4-S3
what nerve roots make up the tibial?
L4-S3
what nerve roots make up the common peroneal?
L4-S2
what nerve roots make up the superficial peroneal?
L4-S2
What nerve roots make up the Deep Peroneal?
L4-S2
What nerve roots make up the superior gluteal
L4-S1
What nerve roots make up the inferior Gluteal
L5-S2
What nerve roots make up the pudendal?
S2-S4 “S2-S4 help keep it off the floor”
what is motor to the tibial and common peroneal?
sciatic nerve
what is sensory to the posterior leg and foot and motor to all muscles back of thigh, leg and foot?
tibial
what is sensory to the anterior leg and dorm of foot and motor to the peroneals, tibias anterior and extension of toe?
Common peroneal
what is motor to the lateral compartment of the leg
superficial peroneal
what is motor to the anterior compartment of the leg?
deep peroneal
what is motor to the gluteus medium, minimum and TFL?
Superior gluteal
what is motor to the gluteus maximus?
inferior gluteal
what is sensory to the muscles of the perineum, and motor to the external anal sphincter?
pudendal