Back Flashcards
How many cervical vertebrae? Thoracic? lumbar? sacral? coccyx?
C - 7 T - 12 L - 5 S - 5 C - 4
Which sections of the vertebral column curve anteriorly ?
Cervical and lumbar
Which sections of the vertebral column curve posteriorly ?
Thoracic and Sacral
What is a static curve
Curve which can not change as the body changes position
What is an example of a static curve
Sacral
What is a dynamic curve
Continuously changing based on body position
What is an example of a dynamic curve
Cervical
Thoracic
Lumbar
What is the purpose of curves in the human vertebral column
To help vertebral column deal with compressive forces
Resistance of vertebral column to compressive forces has strengthened by how much due to the curves
10 fold
what causes the 5 degrees of scoliosis that is considered normal
has to do with handedness - carrying things more with one arm than the other
If you are right handed, in which direction do you get a slight 5 degree curve
towards the left side (compensatory)
How large must a scoliosis curve be for a physiotherapist to step in
15 degrees
At what point would you start to brace someone with scoliosis
30 degrees
If the curve is to the right side where does the hump occur
right side
What are primary curves ? which curves in the body are primary
curves you are born with sacral and thoracic
What are secondary curves? which curves in the spine are secondary
curves that develop later on in life
Cervical and lumbar
when does the cervical curve develop
when baby learns to hold head - ~3 months
When does the lumbar curve develop
when baby starts walking ~18 month
What is the joint between articular surfaces of the vertebrae called?
Zygapophyseal joint
What type of joint is the zygapophyseal joint
Planar synovial joint
What is the fulcrum for most the movement happening in the vertebral column
the zygapophyseal joints
Are the zygapophyseal joints prone to osteoarthritis?
yes
What is the joint between the vertebral bodies
inter-vertebral disc
What type of joint is the inter-vertebral disc
symphysis joint
What type of connective tissue is in the inter-vertebral disc joint
fibrocartilage
What exits via the intervertebral foramen
spinal nerves
What pathophysiologies effect the nerve at the inter-vertebral foramen
hernia and osteoarthritis
What two structures make up the inter-vertebral disc
- Nucleus Pulposus
- Anulus fibrosus
What is the main chemical content of the nucleus pulposus
hyaluronic acid
What does hyaluronic acid do in the nucleus pulposus
attracts and absorbs water into the vertebral discs
Why must water be absorbed into the nucleus pulposus?
To allow it to act as a shock absorber
When does the nucleus pulposus absorb water
when they are not under pressure - during sleep. during the day they are under pressure and lose the water
What is the anulus fibrosus
collagen bundles in between spinal vertebrae
What direction do the anulus fibrosus run? why?
directed at a right angle to the layer before them - this helps with strength
What is the purpose of the anulus fibrosus
to hold nucleus pulposus in place - has no role in compressive forces
How many layers of anulus fibrosus are in the cervical spine? the lumbar>
3-4
up to 20 - due to greater compressive forces
why do we shrink as we age
hyaluronic acid gradually leaks out and in turn you lose your ability to absorb water
How could you diagnose a discal hernia
get patient to cough or sneeze and if this causes shooting pain on the back of thigh
How do discal hernias occur
With too much pressure on disc nucleus propulsus slowly tears layers of the anulus fibrosus one by one
Why do discal hernias get more painful as more layers get torn
inner layers dont have much nerve supply so when the deep layers are ruptured they cause a little pain, but when the outer layers are ruptured they have more pain because they have the most nerve supply
which direction is most common for discal hernia? why?
posteriolateral because direction of herniation is normally the direction that is not very supported by other ligaments
What time of collagen fibres are the anulus fibrosus
fibrocartilage - does not heal again
What is the surgery option for discal hernia
to shave it down but if it is posterior you cant do this so you have to remove lamina to allow the spinal cord to move backwards
What is the PT treatment for discal hernia
strengthening muscles around that area with good exercise plan patient can live pain free for rest of life through providing support
what are 6 supportive ligaments of the spinal cord
- Posterior longitudinal ligament
- Anterior longitudinal ligament
- Interior transverse ligament
- Supraspinous ligament
- interspinous ligament
- Flava ligament
Where does the flava ligament run
between laminae of adjacent vertebrae
The ____ is a continuation of the supraspinous ligament in cervical spine
nuchal ligament
HOw does the nuchal ligament differ from supraspinous ligament
gets wider and bigger
Where is the inter-transverse ligament
running between adjacent transverse processes
What is the continuation of the posterior longitudinal ligament in the upper cervical area
Tectorial membrane
What type of joint is the axis and atlas
synovial pivot joint
why does the atlo-axial joint need a lot of support
medullar oblongata is immediately behind the dens - it controls respiratory cardiovascular and respiratory
which band of the cruciate ligament is more important
the horizontal band
What is the role of the uncinate processs
two little horns on anterior side - gives concanve surface on vertebral body to hold on the disc better.
Where are the uncinate processes normally found
cervical region - most mobile region
What is the found between uncinate process and vertebral body
Joint space
What type of connective tissue is found in joint space
hyaline cartilage
What type of joint exist between the vertebral bodies and the uncinate processes
synovial gliding joint
the ___ matter is in the centre of the spinal cord and surrounded by ___ matter
grey
white
What are the columns of white matter in the spinal cord occupied by
ascending (sensory) and descending (motor) pathways
How long is spinal cord
43-45 cm - has nothing to do with height of person
in 70% of people SC sshould end at…
intervertebral disc L1 and L2
where might SC end in someone who is really tall? really short?
T12
L3
Grey matter is ____ while white matter is ____ (think composition)
cell bodies of neurons
Myelinated fibres
Grey matter has 3 horns and they contain different cell types functionally. What is found in the posterior horn? anterior? lateral?
Sensory
Motor
autonomic
Axons exit spinal cord via…
rootlets
when do rootlets become roots
when they merge with the rootlets of opposite region (ventral with dorsal and vice versa)
When the dorsal and ventral roots join what do you get
spinal nerves
Are spinal nerves mixed fibres
yes
are spinal nerves long?
non - 1cm and immediately divide and split
When spinal nerves divide and split they become…
dorsal and vetral rami
is the dorsal or vantral rami bigger
ventral
do ventral or dorsal rami make the plexi
ventral
dorsal rami run individually and supply…
the deep muscles of the back - also carry some sensory fibres to supply skin
Dura matter is a ___ connective tissue
dense
arachnoid mater is a ___ connective tissue
loose
Pia matter carries _____ into ____
blood vessels into nervous tissue
we have ___ pairs of spinal nerves
31
how many cervical spinal nerves are there
8
In cervical region spinal nerves exit ____ their corresponding vertebrae .
in other regions?
above
below
What are somites
blocks of mesoderman tissue
What does the formation of neural tube have a profound influence on
surrounding mesoderm that leads to the development of somites
each somite differentiates into 2 major groups of cells - these are …
- Sclerotome
- Dermato-myotome
What occurs to sclerotome and dermato-myotome once they migrate to their destication
give rise to bones, skeletal muscles, and dermis
Each somite is associated with…
a branch of the developing spinal cord
What gives rise to the spinal cord and brain
neural tube
What is a somatic nerve
the part of spinal nerves which innervate a somite and its derivative (skin and skeletal muscles)
Are somatic nerves mixed?
yes
Motor neurons develop in the ___ aspect of SC
anterior
Sensory neurons develop from _____
neural crest cells (future dorsal sensory ganglion)
Processes of motor neurons will be carried by ___ and ____ to supply ___ and ___ muscles respectively
ventral and dorsal
Hypaxial and Epaxial
Processes of sensory neurons will pass into posterior aspect of spinal cord or follow the …
dermatomyotomes
What are somatic plexuses formed by
union of anterior rami of spinal nerves
Plexuses are formed at different levels Cervical: Brachial: Lumbar: Sacral:
C - C1-C4
B - C5-T1
L - T12-L4
S - L4-Coccyx
What is a dermatome
area of skin innervated by a single spinal nerve
What is a myotome
part of a skeletal muscle that is supplied by a single spinal nerve
