QUIZ 1 Flashcards
atlantoaxial subluxation
-incomplete dislocation of the median atlantoaxial joint
-rupture of transverse ligament
-complete dislocation -> dens may be driven into:
-upper cervical region of spinal cord -> quadriplegia
-medulla of the brainstem -> death
injury and disease of zygapophysial joints treatment
-denervation of lumbar zygapophysial joints
-nerves destroyed by radiofrequency percutaneous rhizolysis (root dissolution)
-denervation directed at articular branches of 2 adjacent posterior rami bc each joint receives innervation from both the nerve exiting and the superjacent nerve
back pain
-5 categories of structures receive innervation in back and can be sources of pain:
-1. meninges- coverings of the spinal cord
-2. synovial joints- capsules of the zygapophysial joints
-3. muscles- intrinsic muscles of the back
-4. nervous tissue- spinal nerves or nerve roots exiting the IV foramina
-1&2 innervated by meningeal branches
-3&4 innervated by posterior rami
-pain from nervous tissue (compression or irritation of nerves)- referred pain- perceived as coming from skin (dermatome) suppled by that nerve
lower supply to spinal cord
-great anterior segmental medullary artery
-drop in BP, fracture, dislocation, clamping of aorta in artery, occlusion, aneurysm
-paraplegia
-only major arterial supply to the lower thoracic, lumbar, and sacral segments of the spinal cord
labor epidural
-caudal epidural block
-in the sacral canal
-causal epidural anesthesia- through sacral hiatus
-trans-sacral epidural anesthesia- through posterior sacral foramina
straight leg test
lasegue test/sign
local vs chronic back pain
-local- ligamentous
-chronic- spinal nerve roots
spondylolisthesis
-forward displacement of (commonly L5) vertebral body relative to sacrum
-reduced pelvic inlet diameter
-pressure cauda equina as they pass into superior part of sacrum
heterotopic bone
-bone forms in soft tissue not normally present
-due to chronic muscle strain -> small hemorrhagic areas undergo calcification and ossification
6 types of synovial joints
-pivot- uniaxial, rounded process fits into bony ligamentous socket -> rotation- ex. median atlantoaxial joint
-ball and socket- multiaxial, rounded head fits into concavity- ex. hip joint
-condyloid- biaxial, permit flexion, extension, abduction, adduction, circumduction- ex. metacarpophalangeal joint
-saddle- biaxial- ex. carpometacarpal joint
-hinge- uniaxial, permit flexion and extension- ex. elbow
-plane- usually uniaxial, gliding or sliding- ex. acromioclavicular joint
anastomoses, collateral, circulation, and terminal (end) arteries
-smaller channels increase in size -> provide collateral circulation -> ensures blood supply to structures distal to blockage
-collateral circulation takes time -> insufficient for sudden occlusion or ligation
-terminal (end) arteries- do not anastomose with adjacent arteries
-occlusion of terminal artery cuts off supply to organ or structure completely
-functional terminal arteries- arteries with ineffectual anastomoses supply segments of brain, liver, kidney, spleen, intestines
lymphangitis, lymphadenitis, lymphedema
-lymphangeittis and lymphandenitis- secondary inflammation of lymphatic vessels and lymph nodes
-may occur when the lymphatic system is involved in the metastasis of cancer -> lymphogenous dissemination of cancer cells
-lymphedema - the accumulation of interstitial fluid that occurs when lymph is not drained from an area
-when cancerous lymph nodes are removed from axilla -> lymphedema of upper lime may result
Nerve damage
-CNS- proximal stumps begin to regenerate -> send sprouts into area -> however -> growth blocked by astrocyte proliferation -> permanent disability
-PNS:
-axons degenerate distal to lesion bc they depend on cell bodies
-crushing- cell bodies survive -> connective tissue of the nerve guide growing axons to their destinations -> no surgical intervention
-cut nerves require surgery -> apposition of the cut ends by suture through the epineurium -> individual fascicles are realigned
-compression of vasa nervorum-> ischemia -> nerve degeneration
-prolonged ischemia -> severe damage similar to crushing or cutting nerve
layers in peripheral nerve
-endoneurium and neurolemma surround the axons -> fascicle bundled by perineurium -> multiple fascicles bundled by epineurium
spinal cord end
-spans from foramen magnum to L1-L2
-conus medullaris- tapered region at the end of the cord
-filum terminale- filament extending inferiorly from the end of spinal cord in the dural sac and attaches to dorsum of coccyx -> anchors the inferior end of the spinal cord
posterior vs anterior ramus supply
-posterior- intrinsic back muscles, head, neck, zygapophysial joints, skin, trunk
-anterior- muscles, joints, skin of LIMBS, anterolateral trunk
arterial supply to spinal cord
-anterior and posterior spinal artery supply only the short superior part of spinal cord
-run longitudinally from medulla of brain stem to conis medularis
enteric
-autonomic nervous system
-independent
-2 ganglionated plexuses- myenteric and submucosal
-myenteric- longitudinal and circular smooth muscle of GI tract
-submucosal- submucosa
-receive from postganglionic sympathetic or preganglionic parasympathetic
sympathetic and parasympathetic innervations
-sympathetic- T1-L2
-parasympathetic- CN 3, 7, 9, 10 and S 2, 3, 4
-short preganglionic, long postganglionic- sympathetic
-long preganglionic, short postganglionic- parasympathetic
ganglia
-3 cervical- superior, middle, inferior
-12 thoracic
-4 lumbar
-5 sacral
splenic nerves
-afferent and efferent
-abdominopelvic splenic
-greater, lesser, least, and lumbar splenic nerves
-synapse in prevertebral ganglia
-surround the branches of aorta -> celiac aortic or renal, superior and inferior mesenteric ganglion
-celiac ganglion receive input from superior greater splenic nerve -> innervate foregut, distal esophagus, stomach, proximal duodenum, pancreas, liver, biliary system, spleen, adrenal glands
-aortic or renal from the lesser splenic nerve
-superior and inferior mesenteric ganglion from the least and lumbar splenic nerves
intervertebral venous plexus
-in the epidural space
-Batson’s plexus
-drains the entire length of the vertebral column
-This plexus and the external vertebral venous plexus provides a route for metastasis to the vertebrae, spinal cord, or brain from an abdominal (kidney), thoracic (breast and lung), or pelvic (prostate) tumor
-occurs bc lack valves
epidural abcess
-pus between dura mater/spinal cord and bones of spine/skull
-more common in spine bc it is a real space
spinal block
-injected into subarachnoid space into CSF
-below L1/L2
denticulate ligaments
-thickened extensions of pia mater
-traverse the subarachnoid space
-attach to dura mater
-21 pairs
-stabilize spinal cord to prevent side to side motion
disc hernation
-cervical posterolateral herniation- nerve impinged = lower vertebra (C5 is impinged at C4-C5) -> bc cervical nerves exit superiorly
-thoracic posterolateral herniation- nerve impinged = upper vertebrae (T3 is impinged at T3-T4)
-lumbar posterolateral herniation- nerve impinged = lower vertebrae -> because nerve extending to the level below the herniation is impinged in the lateral recess of the vertebral canal
intrinsic back muscles
-maintain posture and move head and vertebral column
-innervated by dorsal rami
-superficial- splenius capitis and splenius cervicis
-intermediate- erector spinae: iliocostalis, longissimus, spinalis
-deep- transversospinalis group (semispinalis)
splenius capitis and cervicis
-superficial layer
-directed superolaterally
-distal attachments are distinct
-capitis- inferior- nuchal ligament and spinous processes of C7-T6
-capitis- superior- mastoid process and superior nuchal line
-cervicis- inferior- SP T3-T6
-cervicis- superior- transverse processes C1-C3/C4
-innervated by dorsal rami of spinal nerves
-action- bilaterally extends head and neck unilaterally laterally flexes and rotates head
erector spinae: iliocostalis, longissimus, spinalis
-intermediate layer
-from lateral to medial -> iliocostalis, longissimus, spinalis (I Love Spines)
-originates on posterior aspects of iliac crests and sacrum, sacroiliac ligaments and spinous processes of sacral and inferior lumbar vertebrae
-inserts on spinous and transverse processes of vertebrae, ribs, skull
-innervated by dorsal rami
-supplied by dorsal branches of posterior intercostal and lumbar arteries
-action- erect posture, bilateral contraction to extend vertebral column, unilateral contraction for rotation
transversospinalis group
-form transverse processes (inferiorly) to spinous processes (superiorly)
-between spinous process and transverse process
-rotation and lateral bending movement
-stabilize vertebral column
-semispinalis is the only visible
semispinalis
-most superficial of transversospinalis
-semispinalis capitis- attaches to occipital bone
-fibers are longitudinal and parallel to vertebral column
-thoracic, cervicis, capitis
-originate on transverse processes of C4-T12
-insert on occipital bone and spinous processes of thoracic and cervical region
-innervated by dorsal rami of spinal nerves
-action- maintain lordosis and balance head on the neck, bilateral contraction- extension of head and neck, unilateral contraction to rotate head and neck
greater occipital nerve
-dorsal ramus of the C2 spinal nerve
-nerve passes through semispinalis muscle and trapezius
-entirely sensory supplying skin on the back of the head
triangle of auscultation
-allows for optimal auscultating lung sounds
-approx at intercostal space 6
-borders:
-laterally- medial border of the scapula (border of rhomboid major)
-medially- ascending fibers of trapezius
-inferiorly- superior border of the latissimus dorsi
suboccipital triangle
-contents- vertebral artery and (C1) suboccipital nerve
-muscles:
-rectus capitis posterior major- medially
-rectus capitis posterior minor
-obliquus capitis inferior- below
-obliquus capitis superior- above
-innervated- suboccipital nerve C1
-greater occipital nerve C2- sensory
-avoid during surgery
atlanto-occipital joints
-most superior joints of the spine
-synovial
-between occipital condyles and superior facets of the atlas (C1)
antlanto-axial joints
-synovial
-between inferior facets of the atlas (C1) and the superior facets of the axis (C2) as well as a synovial pivot joint with the dens (odontoid process of C2 forming the axis of pivot
inferior to atlanto-axial joints: 3 types of joints*
-all vertebrae have 3 types of joints
-1. anteriorly, a symphysis (a midline, cartilaginous joint) including the body of superior vertebrae, an intervertebral disc, and body of the inferior vertebrae
-2&3. posteriorly, 2 synovial facet joints
parts of a vertebrae*
-anulus fibrosus- outer layer, consists of collagen and fibrocartilage and surrounds the nucleus pulposus
-nucleus pulposus- inner layer, a remnant of the notochord
-the inferior- most intervertebral disc sits between the body of L5 and the articular surface of the sacrum at the lumbosacral junction
difference between cervical, thoracic, and lumbar vertebrae
-transverse foramina only present in cervical
-facets/hemifacets for ribs are only present for thoracic
-transverse processes are only bifid for cervical
-spinous process is small and often bifid for cervical
-spinous process if inferior sloping for thoracic
-spinous process if robust, posteriorly projecting for lumbar
Lumbar triangle
latissimus dorsi medially, external oblique muscle laterally, iliac crest inferiorly- site of lumbar hernia
agonist
-prime mover
