Back -Wilson Flashcards
What are the functions of the vertebral column?
- weight support
- erect posture
- bipedal locomotion
- enclose and protects the spinal cord and nerves
Why is the vertebral column in human susceptible to injury?
the weight of the head and neck is supported by the vertebral column to transfer the weight to the lower limbs
Damage to what areas of the spinal cord will cause paraplegia?
damage of the SC below the origin of the brachial plexus (C5-T1) and above the spinal level S4 results in paraplegia
Damage to what areas of the spinal cord will cause paraplegia?
damage of the SC below the origin of the brachial plexus (C5-T1) and above the spinal level S4 results in paraplegia
Damage to what areas of the spinal cord will cause quadreplegia?
damage of SC between C5 -T1 (the origin of the brachial plexus)
Damage to what areas of the spinal cord will cause asphyxiation?
damage to SC at or above the origin of the phrenic nerve (C3-5)
Changes in size of what may result in spinal cord and/or spinal nerve compression?
vertebral foramen
changes in vertebral column can have neurological consequences
The spinal cord extends all the way down to the sacrum. True or false?
FALSE!
Spinal cord ends at L2??????
What is the function of an intervertebral foramen and how is it formed?
spinal nerves come and go through this foramen
it is formed by 2 intervertebral notches
this is a potential site of nerve damage
Bone spurs and a herniated disc could cause what symptoms?
they could each put pressure on the spinal nerves and axons
The vertebral COLUMN is divided into what 5 regions?
cervical: 7 vertebrae (CONSTANT between mammals)
thoracic: 12 vertebrae
lumber: 5 vertebrae
sacral: 5 fused vertebrae
coccygeal: 5 vertebrae
What are the differentiating characteristics between a cervical, thoracic, and lumbar vertebra?
cervical: bifid spine, transverse foramen
thoracic: thoracic costal facets for rib attachment; spine is at an angle (oblique spine)
lumbar: large to support more weight, spine runs horizontally
What causes spina bifida?
incomplete formation of the lamina of the vertebral
What allows for direct access to the vertebral canal to do procedures like epidural anesthesia?
sacral hiatus
What are the different ways to insert the needle for epidural anesthesia?
transsacral epidural anesthesia: needle through the posterior sacral foramen
caudal epidural anesthesia: needle through sacral hiatus
The needle injections of anesthesia are in the epidural space.
One can palpate what processes to inject a needle for epidural anesthesia?
spinous process and cornua of the sacrum
Where are the two sets of curvature of the spine: primary and secondary?
Primary curvatures are in the thoracic and sacral regions
Secondary curvatures are in the cervical and lumbar regions
Most back problems occurs where with regard to primary and secondary curvatures?
where there are transitions between the primary and secondary curvatures
- from cervical to thoracic (lower cervical)
- from lumbar to sacral (lower lumbar)
At birth, what kind of curvature do babies have that does not allow stability when standing bipedally?
a single primary curvature that is convexed posteriorly
thus the center of gravity is too anterior to be stable when standing bipedally
This curvature develops at 1 years of age and allows for walking in babies.
the secondary curvature
this pulls the center of gravity right in front of the vertebral column which is in the core of the body
What is Netter’s vertebral column abnormality?
Kyphosis (hunchback, dowager’s hump): exaggerated primary curvature in the thoracic spine
What are the causes of kyphosis?
- congential
- occupational (Netter sitting and writing the atlas of anatomy)
- TB: bacteria like the vertebral column and can cause abscess
- degenerating discs
- osteoporosis: bone disease that occurs when the body loses too much bone, makes too little bone, or both
- fractures: in the anterior body of the vertebrae for example
What is lordosis?
exaggerated secondary curvature in the lumbar region
What are causes of lordosis?
- pregnancy
- obesity (abdominal)
these both can bring the center of gravity anterior to the spine and thus individuals will shift the center of gravity underneath the spine (body) to keep balanced
What is scoliosis?
excessive lateral curvature of the vertebral
In many cases what are the causes of scoliosis and in what individuals is this condition mainly seen?
idiopathic: of unknown cause
females
some of the KNOWN causes include:
- hemi-vertebra (congenital: vertebrae did not form completely interfering with proper stacking of the vertebrae)
- a short leg
- polio, stroke, herniated disc
The vertebral column articulates with this at a 90 degree angle.
pelvis
When one leg is shorter than other To keep the body’s weight centered, the spine compensates by bending in what direction?
laterally
What muscles keep the vertebral column straight and erect?
Erector spinae:
iliocostalis
longissimus
spinalis
that acts ANTAGONISTICALLY with rector abdominalis (six pack muscle)
How can a stroke cause scoliosis?
Unilateral paralysis/paresis of the back muscles due to stroke, polio, or disease results in no antagonistic action of the true back muscles allowing for one side of the vertebral column to bend laterally like a bow
How can a decrease in the size of the thoracic cage have a life-threatening impact on the cardiopulmonary system?
Kyphoscoliosis (combination of kyphosis and scoliosis) can result in a greatly reduced volume of the thoracic cage. Thus the cage cannot expand the extent it needs to to fully oxygenate blood. Expansion of lung greatly reduced the blood flow and thus the right side of the heart has to work harder to pump blood to the lungs.
What are vertebral longitudinal ligaments?
connective tissue bands that hold bones together
Which ligament runs from the base of the skull to the coccyx? It covers the posterior 1/3 of the vertebra body.
posterior longitudinal ligament
that helps tie together the backs of the bodies of the vertebrae
This ligament is larger than the posterior longitudinal ligament, spanning the entire vertebral column anteriorly. It covers the anterior 2/3 of the vertebra body.
anterior longitudinal ligament
holding the the bodies of the vertebrae in the proper anatomical relationship
The anterior and posterior longitudinal ligaments run the length of the spine, attaching to adjacent centrums (body).
What is the purpose of the ligamentum flavum?
It has a lot of yellow elastic connective tissue that holds of the lamina or roof of the vertebral canal.
allowing the lamina flexibility to go back and forth
What is the 3 column theory?
anterior: anterior 2/3 vertebrae body
middle: posterior 1/3 vertebrae body
posterior: all structures posterior to the posterior longitudinal ligament
Any one column injury is stable.
Two column injury is unstable.
Three column injury is invariably unstable.
Car accidents can cause damage to these columns.
During a car accident, hyperextension (whiplash) injuries of the cervical spine results in the tearing of what?
anterior longitudinal ligament
- which is thick and thus it is difficult to tear the ALL without affecting bone
- you can get a bulging fracture as a result leading to a lot of neck pain for a long time
The vertebral ligaments are so strong that dislocation of the vertebrae usually results in what?
avulsion or vertebral fracture
What is spondylolisthesis?
where one vertebra becomes displaced relatively to one another
thus the vertebral canal is reduced and spinal cord and/or nerves are compressed
individual may suffer neurological symptoms back pain, loss of sensation
What are the two joints associated with the spine?
zygapophyseal (synovial, called facet joint by radiologists); articular surfaces (superior and inferior) are surrounded by a synovial membrane that produces synovial fluid that lubricates bone on bone or cartilage to cartilage movement
intervertebral disc (symphysis): a fibrocartilaginous joint; limited amount of movement; would see in the pubic symphysis
The vertebral column has a wide range of movements. True or false?
TRUEE!!!
- movements BETWEEN adjacent vertebrae is very limited
- however when multiplied by a continuous column of 24 moveable vertebrae, the spine is capable of a wide range of movements
Where does the greatest mobility of the vertebral column occur?
where the secondary curvature becomes primary
- cervical-thoracic (lower cervical)
- lumbar-sacral (lower lumbar)
largest movements occur between these ranges but there’s a price to pay: they are most susceptible to damage
The intervertebral discs account for about 25% of the length of the vertebral column. As one ages, what happens to the intervertebral disc?
the intervertebral discs get smaller because of dehydration (you get shorter as you age)
What is the compact bone or endplate?
where the intervertebral disc attaches to the bones
should be well-defined in a healthy patient
however a patient with osteomyelitis (infection of bone), can have irregular endplates
What is Schmorl node?
the body of the vertebrae hollows out
An upward and downward protrusion (pushing into) of a spinal disk’s soft tissue into the bony tissue of the adjacent vertebrae
- herniation of the intervertebral disc down into the bone itself producing a cavity
- can be a results of aging
- predominantly in the lumbar and thoracic region
- usually asymptomatic
The intervertebral disc consists of what two parts? Which part is derived from the notochord?
annulus fibrosus: fibrous ring of cartilage forming the outside border
nucleus pulposus: is derived from the notochord; is filled with fibrogelatinous pulp
What is structure is responsible for the decrease in size of the intervertbebral disc?
the nucleus polposus
as you become older the nucleus polposus decreases in the amount of water it contains (dehydrates)
from 80% to 50%
full of water–> STIFF
less water–> more flexibility
What is the function of the nucleus polposus?
it’s semi-gelatinous and acts as a shock absorber
when you stand, run or walk, you generate a lot of force and compression on the vertebral column
so when you put a lot of weight on the vertebral column
What happens if the annulus fibrous becomes stretched and aged?
you get a herniated disc when you lose the strength and integrity of the annulus fibrosis
the nucleus polposis herniate DORSOLATERALLY out into the vertebral foramen thus compressing the spinal nerves as they are trying to be distribute the body
What prevents the intervertebral disc from herniating dorsally?
posterior longitudinal ligament
Is there a direct contact between the intervertebral disc and the nerve?
NOO
the edema alone could put enough pressure on the spinal nerve thus affecting nerve function (neurological symptoms, changes in sensation, changes in motor function)
There is herniated disc between L4 and L5. Which spinal nerve is going to be affected?
spinal nerve below L5
compression of roots of L5
A herniation of C7 will compress which spinal nerve?
spinal nerve below C8
If you have a herniated disc you will always have some neurological symptom. True or false?
FALSE!
A herniated disc does not always result into neurological symptoms.
Just because you have neurological symptoms, you cannot always identify a herniated disc.
If you have a herniated disc and neurological symptoms you have a diagnosis????
Which plexus is valveless and connects with veins of the thorax, abdomen, and pelvis. Why is this significant?
internal vertebral plexus
Valveless: blood can go in any direction it wants to
blood can go from cavities in the body to the ver column
this is a route for which cancer can spread (prostate cancer to venous plexus in the vertebral column forming tumors in the spine or skull)
The vertebral column is major a site for metastasis of cancers that initially began in the thorax, abdomen, and pelvis. True or false?
True!!
The back is organized in layers. You should keep track of what layer of muscle you are in. If you know the layer of back muscle you are in you know what it is innervated by!!
FACTSS!!!
The first 3 anatomical layers of the back muscles are derived from what and innervated by what?
hypomere
innervated by the ventral primary rami
The 4th layer of the back muscles AKA the true back muscles is derived from where and innervated by what?
epimere
innervated by the dorsal primary rami
Mediolateral to the neural tube is the somite which gives rise to what embryological structures to form the vertebrae, skeletal muscles of the body, and the dermis of the skin?
sclerotome: vertebrae
myotome: skeletal muscles of the body trunk and limbs
dermatome: dermis
What comprises the first layer of back muscles from the skin?
trapezius
latissimuss dorsi
both of these muscles are involved in the movement of the upper limb
Where is the triangle of auscultation and lumbar triangle?
triangle of auscultation is mediolateral to the trapezius
lumbar triangle is inferolateral to the latissimuss dorsi
The second layer of back muscles consist of which muscles?
levator scapulae
rhomboid minor
rhomboid major
The second layer of back muscles consist of which muscles? Which of them are the true back muscles?
levator scapulae
rhomboid minor
rhomboid major
NONE of them are true back muscles
The third layer of back muscles consist of which muscles?
Respiratory muscles innervated by the ventral primary rami
- serratus posterior superior
- serratus posterior inferior
They are involved in the movement of the rib cage so termed respiratory muscles.
The 4th layer of back muscle AKA true back muscles consist of what muscles?
- splenius: most superficial found in the cervical region
- erector spinae: runs parallel to vertebral column to help keep the spine erect
- transversospinalis: originate from transverse process of vertebrae running obliquely into spine
When you flex the vertebral column or spine, which vertebrae has the largest protrusion?
C7
A horizontal line drawn through which vertebrae will you hit the inferior angle of the scapula?
T7
The summit of the iliac crest is found at what vertebral level?
L4-L5 disc
The dimples on the lower back form what demarcation?
posterior iliac spine S2
The natal cleft can be found at what vertebral level?
S4
