Back and Spine Flashcards
What are 5 functions of the vertebral column?
1) Muscle attachment
2) Mobility
3) Protection
4) Weight transfer
5) Hematopoeisis
What is the primary and secondary curvature of the veterbral column?
Primary:
- fetal position
- thoracic and sacral (dorsal/kyphotic)
Secondary position:
- extension from fetal position → allows for balance of body weight during upright posture and movement
- cervical and lumbar (ventral/lordosis)
What are the 2 joints of the vertebral column?
1) Intervertebral discs (2° cartilaginous)
2) Zygapophyseal joint
- between articular processes
- plane synovial
What are the components of the intervertebral disc?
1) Anulus fibrosus
- thick outer ring of fibrous cartilage
2) Nucleus pulposus
- inner area
3) Cartilaginous endplates
- superior and inferior to nucleus pulposus
What are the 4 general components of each vertebrae?
1) Vertebral body
- weight bearing
2) Vertebral arch
- forms vertebral foramen
- pedicles and laminae
3) Vertebral notches
- indentations superior and inferior to pedicles
4) 7 processes
- 1 spinous (ligament attachment)
- 2 transverse (ligament/muscle attachment)
- 4 articular processes (facet joints)
What are 2 examples of atypical vertebra?
C1 (atlas) and C2 (axis)
What are 4 unique features of the C1 vertebra?
1) No body
2) No spinous process
3) Anterior and posterior arches each w tubercle
4) Superior articular surfaces → occipital condyles
5) Inferior articular surfaces → C2
What are 5 unique features of the C2 vertebra?
1) Dens/odontoid process project up → pivot for atlas and head to rotate
2) Atlas rotates of flat superior articular facets
3) Anterior:
- vertebral body, dens, 2 pedicles, 2 transverse processes
4) Posterior:
- 2 laminae, 2 spinous process
5) Anterior + posterior → vertebral canal
What are 2 nerve plexuses that arise from the cervical region of the spine?
1) Brachial
2) Cervical
What are 3 unique features of typical cervical vertebrae (C3-7)?
Body:
1) Small body
2) Uncinate process
Transverse process:
3) Foramen transversarium allows passage for vertebral vessels
4) Anterior & posterior tubercles with groove for spinal nerve between
Spinous process:
5) Bifid spine
Vertebral arch (6)
What are 4 unique features of thoracic vertebrae?
1) Costal facets (for articulation w ribs)
2) Nearly vertical articular facets directed posterior and anterior for articulation with head of ribs
3) Long sloping spinous process
4) Body larger than cervical, smaller than lumbar
5) Vertebral foramen
6) Intervertebral foramen
What are 4 unique features of lumbar vertebra?
1) Large body
2) Accessory process on each transverse process
3) Mammillary process on each superior articular process
4) Articular facets directed posteromedially and anterolaterally
5) L1 lies on transpyloric plane
What are 2 unique features of the sacrum?
1) Wedge shapes
2) Sacral foramina for passage of sacral spinal nerves
What are 2 unique features of the coccyx?
1) Small
2) triangular
What are the extrinsic muscles of the back?
Superficial:
- connect to appendicular skeleton
- move shoulder girdle and upper limb
i) Trapezius
ii) Latissimus dorsi
iii) Levator scapulae
iv) Rhomboids
Intermediate:
- superficial to respiratory muscles and support respiratory movements
i) Serratus posterior (superior and inferior)
Trapezius:
Function:
Origin:
Insertion:
Innervation:
Trapezius:
Function:
i) elevate scapula (to aid in abduction)
ii) retract scapula and pull inferior
Origin:
i) Skull
ii) Nuchal line
iii) Nuchal ligament
iv) C7-T12 processes
Insertion:
i) Lateral aspect of clavicle
ii) Acromion
iii) Spine of scapula
Innervation:
Spinal accessory nerve (CN11)
Latissimus dorsi:
Function:
Origin:
Insertion:
Innervation:
Latissimus dorsi:
Function: arms
i) extend
ii) adduct
iii) medially rotate
Origin:
i) T6-12 processes
ii) Thoracolumbar fascia
iii) Iliac crest
iv) Lower 3/4 ribs
Insertion:
Bicipital groove of humerus
Innervation:
Thoracodorsal nerve (posterior cord)
Rhomboids:
Function:
Origin:
Insertion:
Innervation:
Rhomboids:
Function: scapula
i) retract
ii) rotate
Innervation:
Dorsal scapular
Minor:
Nuchal ligament + C7-T1 processes → medial of scapular spine
Major:
T2-5 processes → medial border of scapula
Levator scapulae:
Function:
Origin:
Insertion:
Innervation:
Levator scapulae:
Function:
Elevates scapula
Origin:
C1-4 transverse processes
Insertion:
Medial border of scapula above spine
Innervation:
i) Cervical nerves
ii) dorsal scapular nerve
Serratus posterior inferior:
Function:
Origin:
Insertion:
Innervation:
Serratus posterior inferior:
Function:
depresses rib 9-12
Origin:
T11-L2 processes
Insertion:
Inferior border of rib 9-12
Innervation:
Anterior rami of T9-T12
Serratus posterior superior:
Function:
Origin:
Insertion:
Innervation:
Serratus posterior superior:
Function:
elevate ribs 2-5
Origin:
i) nuchal ligament
ii) C7-T3 processes
Insertion:
Superior border of rib 2-4
Innervation:
Intercostal nerves 2-5
What are the intrinsic muscles of the back and what are their general functions?
Superficial:
- move head and neck
1) Splenius
Intermediate:
- extend, laterally flex, rotate spine
- erector spinae group:
2) Iliocostalis
3) Longissimus
4) Spinalis
Deep:
- stabilise spine, rotate, maintain posture
5) Semispinalis
6) Multifundus
7) Rotatores
8) Levator costarum
9) Interspinale
10) Intertransversari
Splenius muscles:
Function:
Origin:
Insertion:
Innervation:
Splenius muscles:
Function:
ipsilateral rotation
Innervation:
posterior rami
Capitis:
Nuchal ligament + C7-T4 spinous processes → mastoid process + nuchal line
Cervicis:
T3-6 spinous process → C1-4 transverse process
What are the 3 muscles of the erector spinae group?
1) Iliocostalis
2) Longissimus
3) Spinalis
Erector spinae group:
Function:
Origin:
Insertion:
Innervation:
Erector spinae group:
Function:
i) Unilateral → lateral flexion
ii) Bilateral → extend spine and head
Innervation:
Posterior rami
Iliocostalis:
angles of lower ribs + cervical transverse processes
Longissimus:
ribs + thoracic/cervical transverse processes + mastoid processes
Spinalis
upper thoracic spinous process + cranium
Semispinalis:
Function:
Origin:
Attachment:
Innervation:
Semispinalis:
Function: head and spine
i) extend
ii) contralaterally rotates
Origin:
C4-T12 transverse processes
Attachment:
C2-T4 spinous process + occipital bone
Innervation:
Posterior rami
Multifundus:
Function:
Origin:
Attachment:
Innervation:
Multifundus:
Function:
stabilise spine
Origin:
span of vertebral column
Attachment:
spinous processes of 2-4 vertebrae above
Innervation:
Posterior rami
Rotatores:
Function:
Origin:
Attachment:
Innervation:
Rotatores:
Function: spine
i) straighten
ii) rotate
iii) stabilise
Origin:
span of vertebral column
Attachment:
lamina and spinous process of vertebrae above
Innervation:
Posterior rami
Levator costarum:
Function:
Origin:
Attachment:
Levator costarum:
Function:
elevate ribs
Origin:
C7-T11 transverse processes
Attachment:
ribs directly below
Interspinale:
Function:
Origin:
Attachment:
Interspinale:
Function:
stabilise spine
Origin & Attachment:
between adjacent spinous processes in cervical and lumbar regions
Intertransversari:
Function:
Origin:
Attachment:
Intertransversari:
Function:
stabilise spine
Origin & Attachment:
between adjacent transverse processes
What are 2 ligaments of the vertebral body and their functions?
1) Anterior longitudinal
- base of skull → sacrum
- limit extension of spine
2) Posterior
- posterior aspect of vertebral bodies from C2→Sacrum
- attached to intervertebral discs + vertebral margins
- limit flexion
- limit posterior herniation of intervertebral disc
What are the 5 ligaments of the vertebral arch and processes?
1) Ligamentum flavum
2) Interspinous ligaments
3) Supraspinous ligaments
4) Intertransverse ligaments
5) Nuchal ligament
Ligamentum flavum:
Origin & attachment:
Function:
Ligamentum flavum:
Origin & attachment:
laminae of adjacent vertebrae
Function:
i) maintain curvature
ii) reinforce posterior wall of vertebral canal
iii) limit flexion of spine
Interspinous ligament:
Origin & attachment:
Function:
Interspinous ligament:
Origin & attachment:
spinous processes of adjacent spinous processes
Function:
limit flexion of spine
Supraspinous ligament:
Origin & attachment:
Function:
Supraspinous ligament:
Origin & attachment:
Tips of spinous processes from C7→sacrum
Function:
maintain upright position
Intertransverse ligament:
Origin & attachment:
Function:
Intertransverse ligament:
Origin & attachment:
Adjacent transverse processes
Function:
i) limit lateral flexion of spine
ii) limit rotation of spine
Nuchal ligament:
Origin & attachment:
Function:
Nuchal ligament:
Origin & attachment:
- continuous with supraspinous ligament
- eternal occipital protuberance, posterior border of foramen magnum → spinous processes of C1-7
Function:
i) site of muscle attachment
ii) limit flexion of spine
The spinal cord is a continuation of the __________ and runs through the ______ to L1/2 ending to form the ___________.
The spinal cord is a continuation of the medulla oblongata and runs through the foramen magnum to L1/2 ending to form the medullary cone.
What are the 2 enlargements of the spinal cord?
1) Cervical
- C4-T1 → brachial plexus
2) Lumbosacral enlargement
- L1-S3 → Lumbar and sacral plexuses
What is the cauda equina?
Nerve roots from L2-S5 that end below spinal cord
What is the filum terminale?
Remnant of caudal part of spinal cord
The anterior rami of spinal nerves provide _________ innervation while the posterior rami provide ______________ innervation.
Anterior: motor and sensory innervation
Posterior: innervation of deep muscles of back, joints of vertebral column and skin
What are the 3 layers of the spinal meninges?
Superficial to deep:
1) Spinal dura mater
2) Spinal arachnoid mater
3) Spinal pia mater
Where is the epidural space found in the vertebral column?
Outside dura mater
What are 2 components of the epidural space?
1) Internal vertebral venous plexuses
2) epidural fat
Where is the subarachnoid space found in the vertebral column?
between arachnoid mater from pia mater
What is the main component of the subarachnoid space in the vertebral column?
Cerebrospinal fluid
The subarachnoid space is enlarges at the level of ____________ to form _______________.
L2-S2
- enlarge around conus medullaris to form lumbar cistern
Which layer of the spinal meninges covers the spinal cord, nerve roots and vessels?
Pia mater
Which layer of the spinal meninges fuses with the filum terminale?
Pia mater
What are the denticulate ligaments?
Bilateral thickening of pia mater between posterior and anterior nerve roots
- attach to dura mater to suspend spinal cord in vertebral canal
Describe the typical arterial supply of the spinal cord.
1) Anterior spinal artery (branch of vertebral arteries)
2) Posterior spinal artery (branch of vertebral/posteroinferior cerebellar anastomosis)
- both run longitudinally from medulla oblongata to conus medullaris
- supported by medullary segmental arteries
3) radicular arteries supply nerve roots
Describe the venous drainage of the spinal cord.
3 anterior, 3 posterior spinal veins
- drain medullary and radicular veins
→ internal vertebral plexus & external vertebral plexus
→ systemic segmental veins/dural venous
Internal vertebral plexus → dural venous sinus
What is lumbar lordosis?
Abnormal increase in curvature in lumbar region resulting in anterior rotation of the pelvis
What is thoracic kyphosis?
Abnormal increase in curvature in thoracic region as a result of erosion of 1 or more vertebrae usually due to osteoporosis
What is scoliosis?
Abnormal lateral curvature and rotation of the vertebrae → asymmetrical weakness of back muscles
Which spinal segments are lumbar punctures usually performed and why?
between L3-5 (minimise any possible risk of injury to spinal cord which ends at L1/2)
Which layer of the spine is cerebrospinal fluid extracted from in a lumbar puncture?
Lumbar cistern (subarachnoid space)
Which layer of the spine is injected during an epidural anesthesia?
Epidural
