ANAT 5010 - unit 3

- splenius capitis

- splenius cervicis

what makes up the spinotransversales group?

- iliocostalis

- longissimus

- spinalis

what makes up the erector spinae group?

- semispinalis

- multifidus

- rotatores

what makes up the transversospinales group?

actions: extend vertebral column (bilaterally), laterally flex and rotate vertebral column to same side (unilaterally)

innervation: DPRs of middle and lower cervical spinal nerves

what are the actions and innervations of the splenius muscles?

origin: spinous processes of CV7, upper TV, ligamentum nuchae

insertion: superior nuchal line of occipital bone, mastoid process of temporal bone

what are the origins and insertions of the splenius capitis?

origin: spinous process of middle TVs

insertion: transverse processes of upper CVs

what are the origins and insertions of the splenius cervicis?

action: extend vertebral column (bilaterally), laterally flex vertebral column (unilaterally)

innervation: dorsal primary rami

what are the action and innervations of the erector spinae muscles?

action: extend vertebral column (bilaterally), laterally flex and rotate vertebral column to opposite side (unilaterally)

innervation: dorsal primary rami

what are the actions and innervations of the transversospinales muscles?

origin: transverse processes

insertion: spinous processes

what are the origins and insertions of the transversospinales muscles?

actions: extend vertebral column (bilaterally), laterally flex and rotate vertebral column to opposite side (unilaterally)

innervations: DPRs

what are the actions and innervations of the semispinalis muscles?

origin: transverse processes of lower CVs and upper TVs

insertion: occipital bone

what is the origin and insertion of the semispinalis capitis?

origin: transverse process of upper TVs

insertion: spinous processes of CVs up to CV2

what is the origin and insertion of the semispinalis cervicis?

actions: extend vertebral column (bilaterally), laterally flex and rotate vertebral column to opposite side (unilaterally)

innervation: DPR

what are the actions and innervations for the multifidus muscles?

actions: extend vertebral column (bilaterally), laterally flex and rotate vertebral column to opposite side

innervation: DPR

what are the actions and innervations for the rotatores muscles?

- obliquus capitis inferior

- obliquus capitis superior

- rectus capitis posterior major

- rectus capitis posterior minor (doesn't actually border)

what muscles make up the suboccipital triangle?

actions: extend head (bilaterally), rotates the head to the same side at the atlantoaxial joint (unilaterally)

innervation: suboccipital nerve (C1 DPR)

what are the actions and innervations of the muscles of the suboccipital triangle?

- vertebral artery -> ascents through transverse foramen of CV6-CV1 then travel medially in the groove over the posterior arch of the atlas

- suboccipital nerve -> emerges between the vertebral artery and CV1

what artery and nerve are in the suboccipital triangle?

occipital artery

branch of external carotid artery; supplies the posterior scalp

greater occipital nerve

branch of C2 DPR; somatic sensory innervation; supplies posterior scalp

starts in the brainstem/foramen magnum

ends in the vertebral disc between LV1 and LV2

where does the spinal cord start and stop?

CV7 and TV1

spinal nerve C8 emerges between - and -

conus medullaris

inferior tapering of spinal cord; end of spinal cord proper

cauda equina

bundle of spinal nerve roots within vertebral canal; "horse's tail"

anterior spinal artery

branch of vertebral artery; unpaired

posterior spinal artery

branch of vertebral artery; paired

dura mater

most superficial meningeal layer; tough; extends from foramen magnum to coccyx

arachnoid mater

intermediate meningeal layer; delicate, spider-web like appearance

pia mater

deepest meningeal layer; adheres directly to the spinal cord

epidural space

space external to dura; contains fat, internal venous plexus

subdural space

space between the dura and arachnoid mater; potential space

subarachnoid space

space between the arachnoid and pia mater; contains CSF, blood vessels, and cauda equina

denticulate ligaments

extensions of the pia mater; anchor spinal cord to dura mater; separate anterior and posterior SC rootlets

filum terminale

extensions of meninges that together anchor the spinal cord to the coccyx

filum terminale internum

extension of the pia mater; inside dural sac/subarachnoid space; terminates at end of sac SV2

filum terminale externum

fused extension of the dura and pia maters; passes through sacral hiatus to coccyx; "coccygeal ligament"

origin: CV2 spinous process

insertion: CV1 transverse process

what's the origin and insertion of the obliquus capitis inferior?

origin: CV1 transverse process

insertion: inferior nuchal line of occipital lobe

what's the origin and insertion of the obliquus capitis superior?

origin: CV2 spinous process

insertion: inferior nuchal line of occipital lobe

what's the origin and insertion of the rectus capitis posterior major?

origin: CV1 posterior tubercle

insertion: inferior nuchal line of occipital

what's the origin and insertion of the rectus capitis posterior minor?