Vertebral column revision Flashcards
how many pairs of spinal nerves?
where are they found?
what do they connect with?
where do spinal nerves emerge?
C1 will emerge from above C1 vertebrae
C8 will emerge below C7 vertebrae
this then continues all the way down
anterior and ventral are same thing
posterior and dorsal are same thing
sensory axon pathway spinal cord?
motor axon?
sympathetic?
spinal nerve composed of?
if thoracolumbar outflow will also have sympathetic outflow
spinal nerve = somatic sensory, motor + sympathetic
(visceral afferents travel alongside sympathetic nerves but are NOT part of the spinal nerve)
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function of spinal nerve?
each spinal nerve pair supplies a body segment with:
- general sensory supply to all structures
- somatic motor supply to skeletal muscles
- sympathetic nerve supply to skin (sweat glands) and to smooth muscle of arterioles
dermatome vs myotome?
dermatome = area of skin supplied with sensory information from a single spinal nerve
(in reality, there is overlap)
myotome = skeletal muscles supplied with motor innervation from single spinal nerve
(again, most muscles not supplied by single spinal nerve)
landmarks dermatope map?
nipple = T4
umbilicus = T10
posterior scalp, neck and shoulder = C2-C4
uppe rlimb = C5-T1
lower limb, gluteal region + perineum = L2-Co1
B = T6
nerve plexuses?
examples?
intertwined anterior rami form a number of adjacent nerves
(NOT posterior rami)
cervical plexus (C1-C4) - posterior scalp, neck, diaphragm
brachial plexus (C5-T1) - upper limb
lumbar plexus (L1-L4) - lower limb
sacral plexus (L5-S4) - lower limb, gluteal region + perineum
(can be referred to toagether as lumbosacral plexus)
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2 enlargements in spinal cord?
cervical (upper limb) + lumbar (lower limb)
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spinal roots fuse to form?
spinal cord terminates?
Roots fuse to form mixed spinal nerve which eventually produces posterior and anterior rami
Spinal cord terminated in cone shape called conus medullaris
Continues as thin connective tissue cordcalled filum terminale which is anchored at dorsum of the coccyx
(if you stand on your head your spinal cord doesn’t come crashing down)
spinal meninges continuous with?
Spinal meninges are continuous with cranial meninges via foramen magnum
meninges layers
Dura mater
Arachnoid mater
Pia mater
spinal cord suspended in canal vi?
formed from?
subarachnoid space?
Spinal cord is suspended in the canal by the denticulate ligament (found laterally)
The ligament is formed of pial and arachnoid tissue
Note - just like in brain, subarachnoid space filled with CSF
spinal cord made up of?
central canal spinal cord?
posterior vs anterior horn position?
opens into 4th ventricle superiorly
posterior = extends all way up to surface of spinal cord
anterior horn does not
(just helps with orientation)
what is present in spinal cord from T1-L2?
small lateral horn which contains the preganglionic sympathetic neurons
arterial supply to spinal cord?
3 major longitudinal arteries
- 1 anterior
- 2 posterior
- originate from vertebral arteries and run the entire length of spinal cord
Segmental arteries
- Derived from vertebral, intercostal and lumbar arteries
Radicular arteries
- Travel along dorsal and ventral roots
artery of adamkiewicz?
derived from?
also known as great anterior radiculomedullary artery
it is largest segmental artery of spinal cord
derived from 9-12th intercostal artery
venous drainage of spinal cord?
extrinsic muscles of the back?
intrinsic muscles of the back?
erector spinae?
attachments?
3 vertical groups of muscles lateral to spine - intrinsic muscles
inferiorly = common tendon attaches to the sacrum and iliac crest
superiorly = individual tendons
- a rib
- transverse process of a vertebra
- spinous process of a vertebra
low back pain may be due to?
erector spinae strain
transversospinalis?
attachments?
deep intrinsic back muscle - located in grooves between transverse and spinous processes
individual muscle fibres attach between:
- a vertebra and the skull
- a vertebra and a rib
- one vertebra and anothe rvertebra
- the sacrum and a vertebra
nerve supply to intrinsic back muscles?
Segmental nerve supply as per dermatome/myotome
- posterior rami!!!!
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function of erector spinae and transversospinalis muscles?
maintain posture
support the spine
extend the spine
- erector spinae - contracts bilaterally
- if unilateral then lateral flexion occurs
movements of spine and associated muscles?
extension = erector spinae and transversospinalis (bilateral)
lateral flexion = erector spinae and transversospinalis (unilateral)
flexion of spine (forward) = psoas major and rectus abdominus
typical cervical vertebre features?
atypical features?
atlanto-occipital joints found?
what are they?
movements?
found between occipital condyles and the superior articular facets of the atlas (3 articulations)
synovial joints with loose capsule
movements = flexion + extension of the neck, lateral flexion and rotation
articulations of atlanto-occipital joints?
main movement?
3 articulations - all synovial
- 2 between inferior articular facets of atlas and superior articular facets of axis
- 1 between the anterior arch of the atlas and the odontoid process of the axis
main movement is rotation
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Cervical vertebrae dislocation?
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spinal and epidural anaesthetic?
spinal anaesthetic layers passed through?
epidural anaesthetic layers passed through?
caudal anaesthesia?
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