Back and Spinal Cord Flashcards
Components of vertebral column
Cervical (7), thoracic (12), lumbar (5), sacrum (about 5 fused), coccyx (3-4 fused)
Curvatures of spine and direction they curve in
2 primary (concave) and 2 secondary (convex)
Is first curvature primary or secondary?
secondary
lamina
separates traverse from spinous process
How do vertebrae create motion?
joints between articular processes
Cervical zygapophysial joint
sloped from anterior to posterior
Motions from cervical vertebrae
rotation, flexion, and extension
Thoracic zygapophysial joint direction and motion
vertical for rotation, flexion, and extension
lumbar zygapophysial joint
processes of vertebrae below are wrapping around processes of vertebrae above
What is the lumbar zygapophysial joint important for?
Stability
Cervical vertebrae
Triangular shaped vertebral canal with small, short vertebral body
Foramen transversarium
Bifurcated spinous process
Foramen transversarium
Provides place for vertebral artery to move down only cervical vertebrae
Atlas
C1
Axis
C2
Axis shape and function
50% of rotation in neck from specialized vertebral body (dens) shaped like a tooth
thoracic vertebrae
Round vertebral foramen, heart-shaped vertebral body, extra articulations for rib and vertebrae (costovertebral joints)
lumbar vertebrae
small triangular foramen and large cylindrical body
Zygapophysial joint
synovial joint that connects articular processes and allows or inhibits spinal motion
intervertebral discs
Solid joint symphyses that connects adjacent vertebrae and shock absorption
parts of intervertebral discs
annulus fibrosus and nucleus pulposus
Annulus fibrosus structure and functon
Ring of fibrocartilage, Limit rotation between vertebrae
nucleus pulposus structure and functon
Gelatinous center, absorbs compression forces
spinal ligaments and location
anterior and posterior ligaments, ligamentum flavum, supraspinous ligament, interspinous ligament, and ligamentum nuchae
anterior vertebral ligament
courses along vertebral body prevents hyperextension of vertebral column
Posterior vertebral ligament
courses along vertebral bodies prevents hyperflexion of the vertebral column
Supraspinous ligament
connects adjacent vertebral spines, resists flexion in head
ligamentum nuchae
thickened extension of supraspinous and interspinous ligaments resists flexion in head
interspinous ligament
between adjacent spinous processes and blends with suprapsinous ligament and ligamentum flava
layers of back
superficial (appendicular), intermediate (respiratory), deep intrinsic
superficial back muscles
Muscles act on scapula and humerus
Intermediate respiratory back muscle function
Superior: elevates superior ribs
Inferior: depresses inferior ribs
Intermediate back muscle innervation
- Superior: anterior rami of upper thoracic spinal n.
* Inferior: anterior rami of lower thoracic spinal n.
Intermediate back muscle characteristic
serrated edges
Deep/intrinsic back muscles
Splenius, erector spinae, and transversospinales, all have attachments within the back
Splenius capitis attachments
Proximal: ligamentum nuchae, spinous processes C7-T4
Distal: mastoid process, skull
Splenius capitis innervation
Posterior rami of cervical spinal nerves
Splenius cervicis innervation
Posterior rami of cervical spinal nerves
Splenius capitis function
Bilaterally: extend head and neck
Unilaterally: ipsilateral rotation of head
Splenius cervicis function
Bilaterally: extend head and neck
Unilaterally: ipsilateral rotation of head
Splenius cervicis attachments
proximal: spinous processes T3-T6
Distal: transverse processes C1-C3
Erector spinae
Iliocostalis, longissimus, and spinalis
Iliocostalis attachment and innervation
lateral attachment, posterior rami of spinal nerves innervation
longissimus attachment and innervation
intermediate attachment, posterior rami of spinal nerves innervation
Spinalis attachment and innervation
medial attachment, posterior rami of spinal nerves innervation
Erector spinae (including iliocostalis, longissimus, and spinalis) function
Bilateral: extend trunk/spine unilateral: laterally flex trunk
Transversospinales groups
Semispinalis (superficial), multifidus (intermediate), rotatoes (deepest)
transversopinales functions
Bilaterally: trunk extension
Unilaterally: contralateral trunk rotation
Spinal cord length in adults and in neonates
Extends from foramen magnum to L1-L2
Extends to L3-L4 in neonates
Conus medullaries
cone-shaped distal end of spinal cord
Filum terminale
extension of pia mater that connects the spinal cord to the coccyx giving tension to stabilize cord
Cauda equina
extension of lumbar and sacral nerves from spinal cord
Spinal cord enlargements and what they supply
Cervical (C5-T1): supplies upper extremity
Lumbosacral (L1-S3): supplies lower extremity
Structure of meninges
Dura mater
Arachnoid mater
Pia mater
Components of pia mater
Denticulate ligaments and filum terminale
Denticulate ligaments
anchor spinal cord to superficial meningeal layers
epidural space
located between periosteum lining bertebral canal and dura mater
Subarachnoid space
located between arachnoid mater and pia mater
Is there a natural subdural space?
NO
gray matter in spinal cord location and component
cell bodies: longitudinal columns and horns
White matter
Axons: bundles/tracts
Central canal
negligible source of CSF
Parts of cross section of spinal cord
Gray and white matter, sulci/fissures, and central canal
Function and location os afferent and efferent nerves
SAME DAVE: sensory and dorsal afferent, motor and ventral efferent
Spinal nerve
both dorsal and ventral roots
what happens when spinal nerve splits?
splits into ant. And post. Rami that contain both sensor and motor fibers
Anterior rami innervates___
all muscles except intrinsic back muscles
Posterior rami innervates____
intrinsic back muscles
What is within spinal cord enlargements and what do they turn into?
form nerve plexuses that eventually form terminal branches supplying individual muscles or groups
spinal roots
contain sensory or motor axons, not both
Spinal nomenclature
spinal nn. C1-C7 named for vertebra below them (causes 8 spinal nerves)
Spinal nn. T1 and caudal named for vertebra above them
Anterior spinal artery
Branch arising from convergence of vertebral aa.
Travel along anterior median fissure
Supplies anterior 2/3
Posterior spinal artery
Branches of post. Inf. Cerebellar a.
Travel along posteriolateral sulci
Suplies posterior 1/3