Deep Back and Suboccipital Triangle Flashcards
function of extrinsic muscles of back
move limbs and perform thoracic proprioception
Function of intrinsic muscles of back
support upright posture and allow movements of the vertebral column, also perform proprioception
Intermediate extrinsic muscles include
serratus posterior and serratus inferior
serratus posterior and inferior function as
either superficial respiratory muscles or proprioceptive
extrinsic back muscles are innervated by
CNXI (accessory nerve)
branches of brachial plexus (anterior rami)
intrinsic back muscles are innervated gby
posterior rami of spinal nerves
function of spenius capitis and splenius cerfvicis
unilaterally flex neck and rotate head to ipsilateral side
bilaterally extend head
categories of intrinsic muscles of the back
splenius muscles
erector spinae group
transversospinalis group
function of erector spinae m
bilaterally: extend vertebral column and head
unilaterally: laterally flex vertebral column - sidebending
muscles considered erector spinae m
iliocostalis (lomburum, thoracis, cervicis)
Longissimus (thoracis, servicis, capitis)
Spinalis (thoracis, cervicis, capitis)
transversospinalis m function
extend, rotate, stabilize segments of the spinal column
deepest layer - occupy trench between transverse and spinous processes
transversopinalis muscle include
semispinalis (most superficial, thoracis, cervicis, capitis)
multifidus (middle, lumbar)
rotatores (deepest, thoracic)
multifidus m
middle layer of transversospinalis m
short, triangular bundles
stabilize vertebrae during location movements of vertebral column
Roratores m
deepest layer of rotator muscles
stabilize vertebrae and assist with local extension and rotatory movements
might be involved in proprioception
minor deep layer/ segmental muscles include
interspinalis m - aid in extension/rotation
intertransversarii m - aid in lateral flexion, bilateral stabilizers
levatores costarum m - elevate ribs, assist in respiration/lateral flexion
posterior rami of spinal nerves innervate
deep back muscles
back sprain definition
injury to ligamentous tissue, or ligament attachment to bone
no dislocation or fracture
excessive extension or rotatio n
back strain definition
common injury due to overly strong contraction
stretching/tearing of fibers
typically erector spinae muscles
dislocation of cervical vertebrae
less tightly interlocked than other vertebrae making them more prone to dislocation - if severe enough can cause damage to spinal cord
suboccipital region refers to
muscle compartment deep to superior part of posterior cervical region
deep to trapezius, splenius, semispinalis m
pyramidal space inferior to external occipital prominence
atlas
c1 - contributes its body to C2 (or axis) as dens (therefore it lacks a vertebral body)
joints of C1 and C2
superior/articular facets
lateral atlantoaxial joint
median atlantoaxial joint (the one that allows you to say no)
ligament that holds the dens in place
the transverse ligament
contents of suboccipital triangle
rectus capitis posterior major m
rectus capitis posterior minor m
obliquus capitis superior m
obliquus capitis inferior m
(Vertebral a and/or occipital a
Posterior rami of C1 (suboccipital nerve) innervation )
obliquus capitis inferior m is unique to the other muscles of the suboccipital triangle in that
it does not directly contact the occipital bone
it makes contact with the atlas
suboccipital muscles perform what function
extension (and one does lateral rotation)
suboccipital n serves
muscles of the suboccipital triangle
branch of psoterior ramus of spinal nerve C1
greater occipital n supplies
skin over neck and occipital bone
branch of posterior ramus of spinal nerve C2
Lesser occipital nerve supplies
Skin of superior posterolateral neck and scalp posterior to external ear
(Branch of anterior rami of spinal nerves C2-C3)
posterior rami nerves C3-C7 supplies
intrinsic muscles of back and overlying skin adjacent to vertebral column
vascular supply to suboccipital region
vertebral artery
first branch off of the subclavian a.
ascends through the transverse foramina of C7->C2
perforate the dura and pass through the foramen magnum
will ultimately join together to form basilar arteries
Soft tissue injury characteristics
acceleration/deceleration syndrome - head is forced forward then snaps back - whiplash injury
typically involves damage to soft tissue, may also involve fractures
Vertebral artery impingement
reduced blood supply to brainstem when vertebral a is blocked/narrowed with movement at atlantoaxial joint
caused by trauma, cervical spine abnormalities, CV disease
Patients present with dizziness/vertigo, confusion
Fracture of atlas
caused by sudden, forceful compression of C1
diving accidents, roll-over car accidents)
may result in quadraplegia
Hangman’s fracture (C2 fracture)
fracture of pars interarticularis
(where are inferior and posterior articular facet comes together)
caused by hyperextension of the neck (being hanged)
severe cases of acceleration/deceleration syndrome
can completely sever the spinal cord
fracture of dens (C2 fracture) 3 types
most common at base - caused by horizontal blow to the head
type 1 - fracture of upper odontoid process
type 2 - fracture of base of odontoid process
type 3 - through odontoid process and into lateral masses of C2
Occipital neuralgia
irritation of greater occipital and lesser occipital nerves
caused by osteoarthirtis of cervical vertebrae, neck injury, muscle spasms in neck, tumors, infection, gout, diabetes
patients present with burning/stabbing pain triggered by neck movement, scalp tenderness, pain behind eyes, headache
muscles responsible for flexion of head (5)
longus capitis, rectus capitis anterior, anterior portion of sternocleidomastoid, suprahyoid and infrahyoid
muscles responsible for extension of head (6)
rectus capitis posterior major obliquus capitis superior minor obliquus capitis superior splenius capitis longissimus capitis trapezius
muscles responsible for lateral flexion of head (5)
sternocleidomastoid obliquus capitis superior rectus capitis lateralis longissimus capitis splenius capitis
