Week 6 Flashcards
How many articulating vertebrae?
24
How many curves in the spine?
4 total
3 movable
How many pairs of spinal nerves?
31
Abdominal muscles
Some sections linked by fascia and tendinous bands
Do not attach from bone to bone
Many small intrinsic muscles act on head, vertebral column, and thorax. What do they do?
Assist in spinal stabilization or respiration.
Too deep to palpate.
How many total vertebrae?
24 articulating
9 fused
7 cervical
12 thoracic
5 lumbar
5 sacrum
4 coccyx
What are C1 and C2 called?
Atlas and Axis
Shapes allow for extensive rotary movements of head to side, as well as flexion/extension
3 normal curves within movable spine (4 total)
Thoracic spine curves anteriorly
Cervical and lumbar spine curve posteriorly
Spinal curves enable it to absorb blows and shock
How do vertebrae change in size?
Increase in size (diameter from cervical to lumbar due to lower back having to support more weight
Bony landmarks of spine
Spinous process
Transverse process
Body
Odontoid process/dens (on axis or C2)
Atlas
first cervical vertebra
Axis
Second cervical vertebra, has dens (odontoid process)
STUDY PICTURES OF DIFFERENCES IN STRUCTURE BETWEEN DIFFERENT TYPES OF VERTEBRAE
:)
Lordosis
increased posterior curvature of lumbar (and often cervical) vertebrae
Kyphosis
increased anterior curvature of thoracic vertebrae
Lumbar kyphosis
reduction of normal lordotic curve, resulting in a flat-back appearance
Scoliosis
lateral curvatures or sideward deviations of spine
How many ribs?
7 True (vertebrosternal)
3 False (between sternal and floating, vertebrochondral)
2 Floating (at very bottom)
Costal cartilage
All ribs attached posteriorly to…
Thoracic vertebrae
Landmarks of the Sternum
Manubrium, body of sternum, and xiphoid process
Where does most movement in the spine occur?
In Cervical and lumbar.
Some slight thoracic movement
Movements of head
Movement between cranium and 1st cervical within other cervical vetebrae
Referred to as cervical movements
Trunk movements
Lumbar motion terminology describes combined motion in thoracic and lumbar
Cervical region ROM
Flexes 45 degrees
Extends 45 degrees
Laterally flexes 45 degrees
Rotates approximately 60 degrees
Lumbar region including trunk movement ROM
Flexes approximately 80 degrees
Extends 20 to 30 degrees
Lateral flexion to 35 degrees
Rotation approximately 45 degrees
Movements
Spinal movements are often preceded by the name given to the region of movement.
Ex. Flexion of trunk at lumbar spine is known as lumbar flexion, and extension of neck is cervical flexion
Pelvic girdle rotates as a unit due to movement occurring in hip and lumbar spine
Spinal flexion
Anterior movement of spine.
In cervical region, the head moves toward chest.
In lumbar region, the thorax moves toward pelvis.
Spinal extension
Return from flexion or posterior movement of spine.
In cervical spine, head moves away from the chest, thorax moves away from pelvis
Lateral flexion (left or right)
sometimes referred to as side bending. Head moves laterally toward the shoulder, thorax moves laterally toward pelvis
Reduction
Return movement from lateral flexion to neutral
Spinal rotation (left of right)
Rotary movement of spine in horizontal plane, chin rotates from neutral toward shoulder, thorax rotates to one side
Which posterior muscles of the thorax are involved almost entirely in respiration?
Diaphragm
- responsible for breathing during quiet rest
- as it contracts and flattens, thoracic volume is increased and air is inspired to equalize the pressure.
- When larger amounts of air are needed, as in exercise, other thoracic muscles have a more significant role in inspiration
Other thoracic muscles’ role in inspiration
- Scalene muscles elevate first 2 ribs to increase thoracic volume
- external intercostals further expand the chest
- levator costarum and serratus posterior - inspiration
- Internal intercostals, transversus thoracis, and subcostales contract to force expiration
Atlantooccipital joint
- Formed by occipital condyles of skull sitting on articular fossa of the 1st vertebra
- Allows capital flexion and extension
Atlantoaxial joint
Atlas (C1) sits on Axis (C2)
Most cervical rotation occurs here
Trochoid or pivot type joint
Most movable joint of any two vertebrae
Minimal movement between any two vertebrae (except antlantoaxial joint)
- cumulative effect of combined movement from several vertebrae allows for substantial movments
- gliding movement between superior and inferior articular processes of facets joints
Vertebral movments
Flexion
Extension
Lateral Bending
Rotation
Intervetrebral discs
- Between and adhering to articular cartilage of vertebral bodies
- annulus fibrosus- outer rim of dense fibrocartilage
- Nucleus pulposus- central gelatinous, pulpy substance
- Become less resilient with age, injury, or imporper use, resulting in a weakened annulus fibrosus
What do intervertebral discs do?
Bear and distribute load
Mobility
Nucleus pulposus
- 80 to 90% water
- Compressive forces reduce water content and shorten the column about 15 to 25 mm/day
Herniated Disc
- When the cartilaginous discs are damaged from an injury, normal wear and tear, or disease, they may bulge abnormally or break open.
- If the herniated disc presses on a nerve root, it may cause pain, numbness, or tingling
