1 - clinical anatomy of spine Flashcards
what are extrinsic back muscles? (4)
- levator scapulae
- rhomboids (major & minor)
- trapezius
- latissimus dorsi
what are attachments for latissimus dorsi?
attaches to spinous process and inferiorly to iliac crests and superiorly to ribs & scapula and onto intertubercular groove on humerus too
what is function of latissimus dorsi?
extend a flexed arm, acts to adduct and internally rotate arm
what is attachment of trapezius? (extrinsic back muscle)
extends superiorly in neck to attach to occipital bone and forward to attach to clavicle
- clavicle, acromium and spine of scapula
what are the rhomboids (extrinsic back muscle) attachments?
from scapula to spinous process
what are attachments of levator scapulae? (extrinsic back muscle)
attaches to cervical vertebrae and scapula
what is main role of extrinsic back muscles?
they all move upper limb. known as immigrant muscles cause although they on back they form with upper limb and more important in moving upper limb than back
what nerves innervate extrinsic back muscles?
all innervation is cervical spinal nerves, except trapezius which is CN XI
what is main role of intrinsic back muscles?
entirely within back, maintain back posture, move spine
what are the 2 groups of muscles that are intrinsic back muscles?
- erector spinae (superficial) - run vertically next to spine
- transversospinalis (deep) - run in gutter between spinous process & transverse process of vertebrae
what is flexion movement of spine?
it’s bending forward (from starting in extended position, bent back)
what happens if erector spinae contracts unilaterally?
then lateral flexion occurs (bend to side)
what is extension movement of spine?
it’s moving back upright from bending forward (in flexed position)
what muscles causes flexion of spine?
psoas major & rectus abdominis (think like use abs to sit up - same movement)
how many vertebrae in adult vertebral column?
33
- 7 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccyx (4 coccygeal)
what are the primary curves of spine called?
primary = same bend a way as baby = kyphosis
- thoracic & sacral are this shape
what are the secondary curves of spine called?
opposite way to baby bend = lordosis
- lumbar & cervical are this shape
what is name and shape of C1?
atlas = has no body or spinous process (has posterior & anterior arch instead)
what is name and shape of C2?
axis = has odontoid process which projects superiorly from body
what is name of C7 and it’s significance?
vertebrae prominens = first palpable
what are differences in shape of vertebral body for thoracic and lumbar?
thoracic = heart shaped (think like at heart level) and lumbar = kidney shaped w large body
what is difference in shape of vertebral foramen in thoracic & lumbar vertebra?
thoracic = circle. lumbar = small triangular
where is intervertebral foramen?
form between adjacent vertebra, spinal nerves found here (like between the vertebra on top of each other)
what are facet joints?
also known as zygapophyseal joints = between articular processes of adjacent vertebrae, can be affected by arthritis
- they’re synovial
where are intervertebral discs? what is there structure?
joints between bodies of adjacent vertebrae, strong attachment, can herniate
- have outer fibrous ring = annulus fibrosus
- have inner soft pulp = nucleus pulposus
what directions do cervical facet joints face?
cervical superior facet - faces posterosuperiorly
cervical inferior facet - faces anteroinferior
what directions do thoracic facet joints face?
superior facet = face posterolateral
inferior facet = face anteromedial
what directions do lumbar facet joints face?
super facet = face medially
inferior facet = face laterally
what is pars interarticularis?
area in between articular processes
what is spondylolysis?
stress fracture at vertebrae in pars interarticularis, can be congenital in kids but also in adults who play sports like football, gymnastics
what is spondylolisthesis?
slipped disc - displacement when stress fracture weakened and shifted whole vertebra
what are ligaments in vertebral column?
- ligamentum flavum
- anterior & posterior longitudinal ligament
- supraspinous ligament
- intraspinous ligament
where is ligamentum flavum found?
between adjacent laminae posterior to spinal cord, it’s short & thick
what is function anterior longitudinal ligament?
anterior is broader and stronger so prevents over extension (bending back to much)
what is function posterior longitudinal ligament?
narrower & weaker, prevents over flexion (bend forward too much)
what does supraspinous ligament connect?
- connects tips of spinous processes
- strong, fibrous
what does intraspinous ligament connect?
- connect superior surface of one spinous process to inferior surfaces of spinous process above it
- weak, membranous
