Suboccipital region Flashcards
what is the origin of the suboccipital nerve
C1 posterior rami
what is the origin of the greater occipital nerve
C2 posterior rami
what is the origin of the lesser occipital nerve
C2-C3 anterior rami
what is the course of the suboccipital nerve
runs between cranium and C1 vertebra to reach suboccipital triangle
what is the course of the greater occipital nerve
emerges inferior to obliquus capitis inferior and ascends to posterior scalp
what is the course of the lesser occipital nerve
passes directly to skin
what is the distribution of the suboccipital nerve
muscles of suboccipital triangle
what is the distribution of the greater occipital nerve
skin over neck and occipital bone
what is the distribution of the lesser occipital nerve
skin of superior posterolateral neck and scalp posterior to external ear
what is the distribution of the posterior rami of C3-7
intrinsic muscles of the back and overlying skin (adjacent to vertebral column)
what is the most superficial muscle of the suboccipital region
trapezius
part of levator scapulae and SCM can also be seen
what muscles form the intermediate layer of the suboccipital region
splenius capitis and splenius cervicis
what is the innervation of splenius capitis and cervicis
posterior rami C1-6
what are the attachments of splenius capitis
ligamentum nuchae and C7-T3 spinous processes to occipital bone (superior nuchal) and mastoid
what are the attachments of splenius cervicis
T3-T6 spinous processes to C1-C2 transverse processes
what is the function of the splenius muscles
bilateral - extend neck and head
unilateral - flex and rotate to same side
what muscle group is found deep to splenius muscles
parts of erector spinae (semispinalis capitis and longissimus capitis)
what are the attachments of semispinalis capitis
C4-T7 transverse processes to occipital bone between nuchal lines
what is the function of semispinalis capitis
extends cervical spine (both)
bend neck to same side and rotates to opposite side (one)
what are the attachments of longissimus capitis
T1-T3 plus C4-C7 transverse processes to mastoid process
what is the function of longissimus capitis
extends head (both)
flexes and rotates head to same side (one)
what is the innervation of the semispinalis and longissimus capitis
posterior rami
the splenius muscles, semispinalis capitis and longissimus capitis work together to do what
extend the head and neck
what 4 muscles attach to the mastoid process
SCM
posterior belly of digastric
splenius capitis
longissimus capitis
what muscles lie deep to semispinalis capitis and longissimus capitis
suboccipital muscles
where are the suboccipital muscles found
between C2, C1 and occipital bone
what is the function of the suboccipital muscles
extend the head
what innervates the suboccipital muscles
suboccipital nerve (one each side)
where does the suboccipital nerve originate
posterior rami C1
what are the parts of the suboccipital muscles
- rectus capitis posterior minor
- rectus capitis posterior major
- obliquus capitis superior
- obliquus capitis inferior
what are the attachments of rectus capitis posterior major
C2 spinous process to inferior nuchal line
what are the attachments of rectus capitis posterior minor
C1 posterior tubercle to inferior nuchal line
what is the function of the rectus capitis posterior muscles
extend head (both)
rotate to same side (one)
what is the innervation of the rectus capitis posterior muscles
suboccipital nerve (posterior rami of C1)
what are the attachments of obliquus capitis superior
C1 transverse process to occipital bone above inferior nuchal line
what is the function of obliquus capitis superior
extend head (both)
tilt head to same side and rotate to opposite side (one)
what are the attachments of obliquus capitis inferior
C2 spinous process to C1 transverse process
what is the function of obliquus capitis inferior
extend head (both)
rotate to same side (one)
what is the innervation of the obliquus capitis muscles
suboccipital nerve (posterior rami C1)
which of the obliquus muscles is smaller and more lateral
obliquus capitis superior
obliquus capitis inferior is larger and passes between what
C2 and C1
the obliquus muscles are found ____ to the rectus capitis muscles
lateral
which rectus capitis posterior muscle is larger
major
rectus capitis posterior minor is more ___ to major
medial
what nerve supplies the suboccipital muscles
suboccipital nerve C1
why is the suboccipital nerve described as having only motor fibres
there is no C1 dermatome for the head and neck
what nerve supplies the skin overlying the suboccipital area
greater occipital nerve C2
what nerve supplies the skin and muscles of the neck
dorsal rami C3
what artery supplies the sub-occipital region
occipital artery
the occipital artery is a branch of what
external carotid
the occipital artery sends a descending branch to anastomose with what
deep cervical artery
the deep cervical artery comes from where
subclavian
where are the vertebral arteries found
within the suboccipital triangle
what are the boundaries of the suboccipital triangle
both obliquus capitis muscles and rectus capitis posterior major
where do the vertebral arteries come from
branch of subclavian in root of neck
the vertebral arteries ascend the neck where
in foramen transversarium of the cervical vertebra
the vertebral arteries cross the superior surface of __ to enter foramen ___
C1
foramen magnum
describe the course of the vertebral arteries
cross the superior surface of C1 to enter foramen magnum
the right and left vertebral arteries unite to form what
basilar artery
how does the basilar artery supply the brain
contributes to the posterior part of circle of willis
that vein runs with the suboccipital nerve
occipital vein
the occipital vein joins what vein
deep cervical vein
the deep cervical vein communicates with what
vertebral veins and brachiocephalic vein
what vein drains the suboccipital region
occipital veins
what venous structure is found at the back of the head/neck
posterior vertebral venous plexus where many small veins communicate with each other
the posterior vertebral venous plexus has communications with what
occipital veins, emissary veins of the skull, longitudinal vertebral venous sinus, veins around vertebral artery etc
the posterior vertebral venous plexus joins what
brachiocephalic vein via the deep cervical vein
what movements occur at the base of the head and top of the cervical region
nodding ‘yes’
shaking ‘no’
where does nodding movement take place
between atlas (C1) and the occipital condyles of the skull
where does shaking of the head take place
rotation between arch of atlas and dens (odontoid) process of axis C2
what kind of joint is between the C1 arch and odontoid
synovial pivot joint
what is the cruciate (also called cruciform) ligament
transverse ligament of atlas combined with superior and inferior longitudinal ligament bands that collectively form a cross shape between axis and occipital bone
the cruciate ligament is a combination of what that collectively form a cross shape between what
- transverse ligament of atlas
- superior and inferior longitudinal ligament bands
- between axis and occipital bone
where does the alar ligament pass between
dens of the axis to the medial sides of the occipital condyles
where does the anterior longitudinal ligament attach
occipital bone
where does the posterior longitudinal ligament attach
becomes the tectorial membrane that also attaches to the occipital bone
where does the ALL attach inferiorly
sacrum
what do the fibres of the ALL do
deep - bind adjacent vertebrae together
superficial - span multiple segments
what does the ALL do
limits extension (anterior to axis of movement)
what does the PLL limit
flexion
what does the PLL become superiorly
tectorial membrane
where does the PLL begin
C2
what movements are possible between atlas and base of the skull (C1 and condyles of the occipital bone)
flexion
extension
lateral flexion
what muscles allow flexion between atlas and base of the skull (C1 and condyles of the occipital bone)
longus capitis
rectus capitis anterior
anterior fibres of SCM
suprahyoid and infrahyoid muscles
what muscles allow extension between atlas and base of the skull (C1 and condyles of the occipital bone)
rectus capitis posterior major and minor
obliquus capitis superior
splenius capitis
longissimus capitis
trapezius
what muscles allow lateral flexion between atlas and base of the skull (C1 and condyles of the occipital bone)
SCM
obliquus capitis superior
rectus capitis lateralis
longissimus capitis
splenius capitis
what muscles cause ipsilateral rotation of the head between atlas and axis
obliquus capitis inferior
rectus capitis posterior major and minor
longissimus capitis
splenius capitis
what muscles cause contralateral rotation of the head between atlas and axis
SCM
semispinalis capitis
how many cervical vertebrae
7
what are the atypical cervical vertebrae
C1 C2 C7
(C3-C6 typical)
C3-C6 (typical) have what kind of spinous process
bifid
C3-C6 (typical) have what in each transverse process
foramen transversarium
C1 does not possess
a body
how does C1 articulate with the skull
occipital condyles
how does C1 articulate with C2
facet on anterior arch articulates with odontoid process of axis
describe the spinous process of C2
large
describe the spinous process of C7
large, non-bifid
what is another name for C7
vertebra prominens
what kind of joints are between the vertebral bodies
secondary cartilaginous (IVD)
what kind of joints are between the articular processes of vertebrae
plane synovial facet joints
what movements are possible between the cervical vertebrae
flexion
extension
lateral bending
rotation
- small movements at each level collectively form a larger movement of the neck as a whole
what muscles cause flexion of the cervical region
bilateral action of longus coli, scalene, SCM
what muscles cause extension of the cervical region
deep neck muscles
- semispinalis cervicis and iliocostalis cervicis
- splenius cervicis and levator scapulae
- splenius capitis
- multifidis
- longissimus capitis
- semispinalis capitis
- trapezius
what muscles cause lateral bending
unilateral action of iliocostalis cervicis, longissimus capitis and cervicis, splenius capitis and cervicis, intertransversarii and scalenes
what muscles cause rotation of cervical region
unilateral action of rotatores, semispinalis capitis and cervicis, multifidis, splenius cervicis