Back Flashcards
How many vertebrae do we have in the axial skeleton?
33; 24 mobile, 9 fused
What are the functions of the vertebral column?
protect spinal cord and spinal nerves, posture and locomotion
What are the movements of the vertebral column?
extension/flexion, lateral flexion, rotation
Describe the curvature of the vertebral column
alternating lordosis and kyphosis
kyphosis
primary curvature of the spine (thoracic and sacral)
concave anteriorly and develop early in ontogeny when the entire vertebral column is concave anteriorly
Lordoses
secondary curvature of the spine (cervical and lumbar)
concave posteriorly and develop during infancy, as infant learns to hold head up and sit up right and walk, respectively
What are the types of abnormal vertebral column curvatures?
excessive thoracic kyphosis
excessive lumbar lordosis
scoliosis
Describe excessive thoracic kyphosis
exaggerated thoracic curvature “hump back” deformity
Describe excessive lumbar lordosis
exaggerated lumbar curvature “sway back”
deformity
Scoliosis
lateral deviation coupled with a rotational component
Vertebral body
located anteriorly on vertebrae
articulates with intervertebral discs
supports body weight so gradually increases in size from cervical to sacral
vertebral (neural) arch
located posterior to the vertebral body, consists of 2 pedicles and 2 lamina
articular processes
2 superior and 2 inferior projections at the junction of pedicle and lamina
vertebral canal
bony canal formed by adjacent vertebral foramina, contains spinal cord and associated structures
vertebral notches
2 superior and 2 inferior vertebral notches per vertebra, located on the superior or inferior aspect of the pedicles
adjacent superior and inferior notches help form an intervertebral foramen
intervertebral foramen
blood vessels and nerves transverse this foramen
cervical vertebrae
n=7
small vertebral bodies, bifid spinous process
posteriorly projecting spinous process, have transverse foramina for the passage of the vertebral arteries and veins
also have uncinate processes
vertebra prominens
vertebra C7
has the most prominent cervical spinous process
Atlas
C1
lacks a vertebral body and spinous process; ring shaped
superior articular facets for articulation with the occipital condyles of the cranium
Axis
C2
dens process is the portion of the C1 vertebral body that is incorporated into the C2 vertebra during development
Thoracic vertebrae
n=12
spinous processes are long and slender and slant inferiorly to the level of the vertebral body below
heart shaped bodies, looks like giraffe
have costal facets on vertebral bodies and transverse processes for articulation with ribs
lumbar vertebrae
n=5
robust; large bodies
posteriorly projecting spinous processes
looks like a moose
What level of the vertebral column is best for spinal taps?
lumbar, due to large gaps between adjacent vertebrae in lumbar region
lumbosacral angle
marks the junction of the L5 vertebra and sacrum
sacrum
5 sacral vertebrae fuse into one triangular shaped bone, vertebral canal continues as sacral canal which ends at the sacral hiatus
sacral hiatus
an opening at the inferior sacrum that can be used for administering epidural anesthesia
coccyx
4 coccygeal vertebrae fuse into one triangular-shaped bone
focal point for muscle and ligament attachment
What are the functions of IV discs?
distribute force/weight, provide flexibility to vertebral column
Cervical/lumbar IV discs are thicker anteriorly
What are the component of IV discs?
anulus fibrosus - outer fibrocartilaginous ring
nucleus pulposus- gelatinous center mass
Joints of the vertebral bodies
cartilaginous (symphyses) joints, consisting of IV discs & ligaments
there is also uncovertebral joints and facet joints
uncovertebral joints
of Luschka, located between uncinate processes of cervical vertebrae and body of adjacent vertebrae
site of bone spur formation, causing neck pain
Facet (zygapophysial) joints
synovial joints between articular processes of adjacent vertebrae
permits gliding movements between vertebrae-orientation of facets determines ROM
cervical articular facets
face superiorly and inferiorly, permit flexion, extension, lateral flexion and rotation
thoracic articular facets
face anteriorly and posteriorly, permit rotation and restrict flexion/extension and lateral flexion
lumbar articular facets
face medially and laterally, permit flexion/extension and lateral flexion and restrict rotation
Atlanto-occipital joints
synovial joints between the atlas and axis
primary motion is flexion/extension of the head “yes”
What is the vertebral level of the inferior angle of the scapula?
T7
vertebral level of iliac crests
L4
The skin and fascia of the back receive segmental nerve supply via…
dorsal rami
nuchal ligament
cervical thickening of the supraspinous ligament
attaches superiorly to the external occipital protuberance and inferiorly to spinous processes of cervical vertebrae
thoracolumbar fascia
dense sleeve of fascia in thoracic & lumbar regions, site of muscle attachment, surrounds the intrinsic back muscles
What innervates the extrinsic (SF) muscles of the back ?
ventral rami
except for trapezius ( cranial nerve XI, accessory nerve)
What are the extrinsic muscles of the back acting on the UE?
trapezius, latissimus dorsi, lavator scapulae, rhomboid minor and rhomboid major
What is the triangle of auscultation?
the small region, free of overlying superficial muscles, bounded by the trapezius, latissimus dorsi and the scapula
lack of muscle allows for more efficient use of stethoscope to listen to the sounds of the thoracic cavity
What are the 2 extrinsic muscles involved in respiration?
serratus posterior superior and serratus posterior inferior
these muscles are deep to the rhomboids and latissimus dorsi
What innervates the intrinsic muscles of the back?
dorsal rami
What are the functions of the intrinsic muscles of the back?
primarily extension of the vertebral column but also lateral flexion and rotation
these muscles are commonly injured
Superficial layer of intrinsic muscles of the back? Actions
Splenius capitis and splenius cervicis
extend neck- when contracting bilaterally
lateral flexion & rotation of neck to ipsilateral side (when contracting unilaterally
Intermediate layer of intrinsic muscles of the back? Action?
erector spinae- 3 columns
- iliocostalis
- longissimus
- spinalis
common origin: iliac crest, sacrum, lumbar spinous processes
Insertion of iliocostalis
ribs, transverse processes
insertion of longissimus
transverse processes, mastoid process
insertion of spinalis
spinous processes, occipital bone
Action of erector spinae muscles?
extend vertebral column (when contracting bilaterally, lateral flexion & rotation of vertebral column to ipsilateral side (when contracting unilaterally )
Deep layer of intrinsic muscles of the back? origin?
transversospinalis- 3 parts (SF-deep)
- semispinalis
- multifidus
- rotatores
occupy “gutter” between transverse and spinous processes
Action of transversospinalis?
extend vertebral column
stabilize vertebrae
rotation to contralateral side
