Back Muscles and Bones Flashcards
Where are the thoracic vertebrae and how many are there?
between cervical and lumbar- 12
Where are the lumbar vertebrae and how many are there?
Below the lumbar- 5
Where is the sacrum? Describe its composition.
Below the lumbar. It has 5 fused vertebrae.
What is the coccyx. Where is it?
The coccyx is at the bottom of the spine and is 3-4 fused vertebrae
What are the 3 main components of the typical vertebrae?
Vertebral arch- process eminating out of body
Vertebral body-
Vertebral foramen
List and describe the features of the vertebral arch
Pedicle- connects vertebral body to transverse process
Transverse process- process that stick out sideways
Lamina- notch between transverse and spinal process
Spinous process- sticks out perpendicular to spinal cord
Superior/Inferior processes- stick out up and down with articular cartilage to allow for articulation between adjacent vertebrae
Superior/Inferior notches- notches on the top and bottom of the pedicle between the vertebral body and superior/inferior processes
What are C1 and C2?
Atlas and axis
Describe the transverse foramens.
Found in all cervical vertebrae except C7, foramen on either side of the body carrying cerebral arteries
Describe the bifid spinous process.
Spinous process characteristic of cervical vertebrae (double tipped)
Describe unicate processes.
A ridge found on the lateral edge of the top of cervical vertebrae bodies.
Describe vertebra prominens
C7 spinous process- large and can be seen at the back of the neck
Characteristics of thoracic vertebrae
long sloping spinous processes and costal facets for articulation with ribs
Characteristics of lumbar vertebrae
Large sturdy vertebral bodies with blunt spinous processes.
Anterior and posterior saccral foramina
holes in the sacrum
Describe the vertebral canal
canal that houses the spinal cord and runs through the intervertebral foramen
Describe the sacrum canal
The vertebral canal as it enters the sacrum. It comes to an end at the saccral hiatus.
Intervertebral foramina
Holes formed through vertebrae by the superior and inferior processes
Symphsis
two bones connected by cartilage- vertebral bodies are connected by symphsis joints,. cartilage that connects is the intervertebral disc
intervertebral disc
cartilage that connects the vertebrae. outer layer of fibrocartilage (anulus fibrosis) and a gelatin core (nucleus pulposus)
facet (zygapophyseal) joints
synovial joints between interior and superior processes that allow vertebrae to articulate with one another
anterior longitudinal ligament
on the anterior of the spine, prevents hyperextension
posterior longitudinal ligament
prevents hyper flexion of the spine
supraspinous ligament
runs from c7 to sacrum along spinous processes to prevent flexion
ligmentum nuchae
replaces the supraspinous ligament above c7 and attaches at the occipital protuberance. helps support the weight of the head
interspinous ligaments
fills in the gaps between spinous processes
ligamentum flavum
connects adjacent laminae and forms part of the posterior wall of the vertebral canal. Especially prominent in the lumbar region.
primary curvatures
in the thoracic and sacral regions- concave anteriorly from embryo
secondary curvatures
cervical and lumbar- convex anteriorly. not fully developed until after birth and the baby learns to stand
kyphosis
hunchback
lordosis
overextended lumbar
scoliosis
lateral bending of spine
occipital chondyl
prominence surrounding foramen magnum
foramen magnum
hole at the base of the skull for spinal cord
acromion
part of the scapula- the process at the edge of the ridge
scapular spine
ridge running transversely across the scapula
inferior angle of the scapula
the bottom of the scapula
inferior and superior nuchal lines
lines leading to occipital protuberance
mastoid process of the temporal lobe
bottom process on the lateral side of the temporal lobe
Where are the cervical vertebrae and how many are there?
top- 7
Describe the different layers of back muscles and what they are innervated by
extrensic- contains the superficial and intermediate levels. superficial muscles move the upper extremities and intermediate muscles control respiration. innervated by ventral rami
intrinsic- contains deep muscles that stabilize and move the axial skeleton. dorsal rami
What are the extrensic muscles? What are they innervated by?
trapezius, latissimus dorsi, levator scapula, rhomboid major and minor. innervated by the ventral rami (except traps)
OINF Trapezius
O- superior nuchal line, external occipital protuberance, liamentum nuchae, spinous process of C7-T12
I- lateral 1/3 of clavicle, acromion process, spine of scapula
N- accessory nerve
F- superior fibers elevate and laterally rotate scapula
middle fibers retract scapula
inferior fibers depress and laterally rotate scapula
OINF Levator scapula
O- Transverse processes of C1 to C4
I- Superior angle of scapula
N- dorsal scapular nerve
F- elevates scapula
OINF Rhomboid Minor
O- spinous processes of lower cervical and upper thoracic vertebrae
I- medial border of the scapula (superior to spine)
N- dorsal scapular nerve
F- retracts and medially rotates the scapula
OINF Rhomboid Major
O- Spinous processes of lower cervical and upper thoracic vertebrae
I- medial border of scapula (inferior to scapular spine)
N- dorsal scapular nerve
F- retracts and medially rotates the scapula
OINF Latissimus dorsi
O- Spinous processes T7-L5, sacrum, illiac crest
I- intretubercular groove of the humerous
N- thoracodorsal nerve
F- extends, adducts, and medially rotates the humerus
Name the muscles of the intermediate back layer
serratus posterior superior and serratus posterior inferior
OINF splenius capitis & cervicis
O- ligamentum nuchae, spinous processes of C7 and upper thoracic vertebrae
I- capitis- mastoid process and superior nuchae line
cervicis- transverse processes of upper cervical vertebrae
N- dorsal rami of spinal nerves
F- bilaterally, extend the head and neck , unilaterally- rotate the head to one side
OINF- erector spinae
O- sacrum, iliac crest, ribs, transverse processes of vertebrae
I- Spinous and transverse of vertebrae, ribs, skull
N- dorsal rami of spinal nerves
F- bilaterally- extend the head and trunk, unilaterally- bend the trunk laterally and controlling flexion against gravity
ONIF semispinalis capitis
O- transverse processes of lower cervical and upper thoracic vertebrae
I- occipital bone near nuchal lines
N- dorsal rami of spinal nerves
F- bilaterally- extend the head and neck, unilaterally- rotate head to the side
What is the skin of the back innervated by?
Dorsal rami
Describe the organization of blood vessels in the spine
Blood vessels from the descending aorta associated with the thoracic vertebrae are posterior intercostal arteries. Blood vessels associated with the lumbar vertebrae are the lumbar arteries
Describe the development of the paraxial mesoderm
During the 3rd week, the paraxial mesoderm begins to organize into somites, starting in the occipital region. Each somite then goes on to form a sclerotome, dermatome, and myotome
Describe a sclerotome
forms bones, ribs, part of intervertebral disc (annulus fibrosis), and connective tissue. comprised of loosely organized mesenchyme from the center of the somite which migrate around notochord and neural tube
Describe a myotome
produces a layer along the lateral aspect of the embryo. goes on to differentiate into the dorsally located epaxial (intrinsic muscles) group and ventrally located hypaxial group (ventrolateral body wall and muscles of the limbs)
Describe a dermatome and its different potential meanings
spreads out to form the epidermis of the back from the somite in an embryo. In an adult, the dermatome is the area of skin innervated by a pair of spinal nerves.
