Wvsom Fom 9-2-14

Front 1

[OPP - Back Pain]

1. Characterize low back pain as either acute, subacute, or chronic

Back 1

Acute lasts less than 6 weeks,

Subacute lasts between 6 and 12 weeks,

Chronic persists for more than 12 weeks

Front 2

[OPP - Back Pain]

2. Discuss the prognosis of acute low back pain

Back 2

At least 60% of patients with acute low back pain return to work within one month while Ninety percent return within 3 months regardless of the treatment applied. Recurrent back pain occurs in 25-62 percent within 1-2 years with 33% having moderate pain and 15% having severe pain.

Front 3

[OPP - Back Pain]

3. Discuss mechanical versus non-mechanical lower back pain.

Back 3

The mechanical form accounts for 97% of all low back pain. Structurally it involves muscles, nerves, bones, and joints while functionally or posturally it involves the existence of a somatic dysfunction.

The non-mechanical form of back pain accounts for 3% and is associated with Referred or visceral causes such as cancer, infection, inflammatory arthritis, and viscerosomatic reflexes.

Front 4

[OPP - Back Pain]

3. Discuss the attributes of mechanical low back pain.

Back 4

85% of patients are unable to be provided a pathoanatomical diagnosis.

common causes are sprains of ligaments, strains of muscles, degenerative disc disease, disc herniation, spinal stenosis, osteoporotic compression fracture, spondylolisthesis, traumatic fracture, congenital disease, or postural instability / scoliiosis.

Front 5

[OPP - Back Pain]

3. What are the initial treatment modalities for mechanical back pain?

Back 5

OMT, physical therapy, ice and heat, and medications such as NSAIDS, muscle relaxants, opioids, etc.

Front 6

[OPP - Back Pain]

4. List the red flag categories for potentially serious spinal pathology.

Back 6

Possible Fracture, Infection or tumor, cauda equina syndrome

Front 7

[OPP - Back Pain]

4. Discuss the Red flags of lower back pain associated with possible fractures.

Back 7

Major trauma includes an MVA, fall from ~2 stories, or physical assault.

Minor trauma includes osteoporosis, metabolic bone disease, or malignancy.

-The pain is usually axial, non-radiating, severe, and disabling.
-The pain usually begins immediately following the trauma

Front 8

[OPP - Back Pain]

4. Discuss the Red flags of lower back pain associated with a possible infection or tumor.

Back 8

Cancer is a risk, especially in people below 20 years old or greater than 50, people with a history of cancer, unexplained weight loss, or failure to improve after 4-6 weeks with conservative therapy.

Without the above risk factors, the risk of cancer can be ruled out with 100% sensitivity.

The primary risk factors are IV drug use, Immuno-suppression, fever or chills.

Lastly, if the pain worsens when supine or at nighttime, which are conditions where the pain usually lessens.

Front 9

[OPP - Back Pain]

4. Discuss the Red flags of lower back pain associated with a possible cauda equina.

Back 9

This results from any lesion that compresses the cauda equina nerve roots with symptoms such as lower back pain, unilateral or bilateral sciatica, variable lower extremity motor or sensory loss, saddle sensory anesthesia, bladder & bowel dysfunction, or erectile dysfunction in men.

This is a surgical emergency.

Front 10

[OPP - Back Pain]

4. Discuss the recovery rates with cauda equina syndrome.

Back 10

Bowel, bladder, and sexual functions are the least likely to fully return and take the longest to show signs of recovery.

Front 11

[Overview & Development of the Back]

2. Describe the neural tube differentiation.

Back 11

The Neural tube differentiates into: neuroepithelial layer which gives rise to all spinal neurons & some support cells.

The Mantle layer is formed by the neuroepithelial cells that divide & differentiate into neuroblast cells.

The marginal layers is the region that will contain the white matter.

Front 12

[Overview & Development of the Back]

2. Describe the spinal cord development.

Back 12

The neural tube thickens and the cells of the mantle layer differentiate into the Alar plate and the Basal plate. The Alar plate becomes the posterior horn with the sensory nerves while the Basal plate becomes the anterior horn with the motor nerves. There is an intermediate horn between these two that contains no cell bodies.

Front 13

[Overview & Development of the Back]

3. Compare and contrast the locations of various cell bodies, the pathways that motor vs. sensory neurons traverse along the typical spinal nerve.

Back 13

The spinal nerve development includes:

The spinal ganglia cells which are derived from neural crests that become the sensory root axons to the dorsal horn.

The Anterior horn cells become the motor root axons (to myotomes)

While the Intermediate horn becomes sympathetic cells of the ANS with no cell bodies.

Front 14

[Overview & Development of the Back]

3. Describe the differences between the Posterior Ramus and the Anterior Ramus.

Back 14

The posterior ramus contains the motor & sensory nerves to the dermomyotomes of the back.

The Anterior ramus contains the motor & sensory nerves to the dermomyotomes of the body wall & limbs.

Front 15

[Overview & Development of the Back]

3. Describe the differences between the Anterior versus Posterior roots.

Back 15

The anrior root transmits only motor fibers while the posteterior root transmits only sensory fibers. The posterior root also contains the posterior root ganglion (also called the spinal ganglion)

Front 16

[Overview & Development of the Back]

4. Describe the currently needed dermatome regions.

Back 16

C3 =Neck,

T4 = Nipple,

T10 = Umbilicus,

L1 = inguinal line,

C8 = 5th digit of the hand,

C6 = pollex,

L4 = Knee,

L5 = anterior ankle & foot,

S2 = posterior lower limb

Front 17

[Overview & Development of the Back]

Where would you perform a lumbar tap on an adult?

Back 17

L3-L4 or inferior

Front 18

[Overview & Development of the Back]

Where would you perform a lumbar tap on a child 2 years or younger?

Back 18

L4-L5 or inferior

Front 19

[Overview & Development of the Back]

5. Compare & contrast the clinical malformations of the spinal cord.

Back 19

1. Spina bifida occulta is the condition where no spinous process or lamina covers the posterior portion of the vertebrae

2. Meningocele is where the vertebrae is lacking the spinous process & lamina covering the posterior region and while the spinal cord itself remains within the vertebral confines, the arachnoid & subarachnoid region push outward.

3. Meningomyelocele is where the spinal cord is no longer within the vertebral foramen but is pushed into an external pouch posterior to the vertebrae

4. Rachischisis is where the posterior neuropore of the neural tube fails to close

Front 20

[Overview & Development of the Back]

6. Describe the fate of the notochord.

Back 20

The notochord eventually becomes enveloped by the sclerotomal mesenchyme and is ultimately just the nucleus pulposus in the intervertebral disc.

Front 21

[Overview & Development of the Back]

What are the three layers wrapping the spinal cord?

Back 21

The dura mater, arachnoid mater, and the Pia mater.

Front 22

[Overview & Development of the Back]

7. Compare and contrast the relationship between the vertebral level and the end of the spinal cord at birth and in adulthood.

Back 22

At the embryo stage, the spinal cord runs the full length of the vertebral canal.

At the 6 months gestation, the spinal cord ascends to the ~S1 level.

In the Newborn, the spinal cord is at the ~L2-L3 level.

In the Adult, the spinal cord is at the ~L1-L2 level.

Front 23

[Overview & Development of the Back]

7. Describe Spondylolysis.

Back 23

Spondylolysis is a fracture in the interarticular parts of the lamina. Most commonly occurs between L5 and S1

Front 24

[Overview & Development of the Back]

8. Compare & contrast the relationship between vertebral level & spinal cord segments in the adult.

Back 24

Because the spinal cord is shorter than the length of the spinal canal, the relationship of the spinal cord segments to the vertebral levels is not 1 to 1.

The inferior vertebral levels are associated with more caudal spinal cord segments.

Front 25

[DS Embryology]

What are the developmental stages of concern?

Back 25

Cleavage

Bilaminar

Trilaminar

Front 26

[DS Embryology]

Describe where fertilization usually occurs.

Back 26

Fertilization occurs in the ampulla of the fallopian tube.

Front 27

[DS Embryology]

Describe the concept of polyspermy.

Back 27

When more than one sperm fertilizes an egg, multiple copies of the genetic code combined into polyploidy resulting in malformations or death.

Front 28

[DS Embryology]

What are the multiple blocks to polyspermy?

Back 28

The Corona Radiata, Zona Pellucida, and the Cortical Reaction

Front 29

[DS Embryology]

Describe the Corona Radiata.

Back 29

It is the first barrier to polyspermy. It is a layer of cuboidal cells surrounding the egg that screens for capacitated sperm. These sperm penetrate the barrier by the secretion of proteolytic enzymes.

Front 30

[DS Embryology]

Describe the Zona Pellucida.

Back 30

This is the second barrier to polyspermy. When sperm contact the zona, the acrosome reaction occurs, where a cap surrounding the sperm head ruptures. The acrosome releases digestive enzymes that dissolve the glycoproteins of the zona.

Front 31

[DS Embryology]

Describe the zona reaction.

Back 31

this is the final barrier to polyspermy. Sperm penetrate the zona to reach the plasma membrane. This process induces the rupture of the cortical granules lining the ovum's plasma membrane. The enzymes (such as peroxidases) are released (this is the cortical reaction) inactivate the receptors for spermatozoa binding to the surface of the zona. No further sperm can bind or penetrate into the ovum.

Front 32

[DS Embryology]

Explain the process and relevance of compaction during the Morula stage.

Back 32

The blastomeres of the 8 or 16 cell embryo are pulled closer together by tight junctions into an inner cell and outer cell.

Front 33

[DS Embryology]

In the Morula stage, what does the Inner cell differentiate into versus those in the outer cells?

Back 33

Those blastomeres that pull toward the center are committed to differentiate into both fetal and extra-embryonic tissues while the blastomeres that remain around the perimeter (outer cells) are committed to differentiating into solely extra-embryonic tissues.

Front 34

[DS Embryology]

Describe the derivations and fates of all components of the cleavage stage embryos from morula to implant

Back 34

In the blastocyst, the Inner cell mass becomes the Embryoblast while the outer cell mass becomes the trophoblast.

Front 35

[DS Embryology]

What happens to the trophoblast as it nears the uterine mucosa?

Back 35

The trophoblasts secrete proteolytic enzymes that assist in the penetration of the epithelial cells of the uterine mucosa.

Front 36

[DS Embryology]

When is the zona pellucida removed?

Back 36

The zona pellucida is removed upon reaching the Uterus.

Front 37

[DS Embryology]

Describe the syncytiotrophoblast.

Back 37

The syncytiotrophoblast is a new layer produced from the trophoblast after implantation. The trophoblasts release their nuclei into an extended, continuous cytoplasm called the syncytium. This syncytiotrophoblast expands & penetrates into the endometrial stroma, drawing the blastocyst behind it.

Front 38

[DS Embryology]

What is the name for the remnant of the trophoblasts after they have expelled their nuclei into the syncytium.

Back 38

Cytotrophoblasts

Front 39

[DS Embryology]

Describe the locations in the bilaminar stage of the Epiblast, Amnion, Amniotic cavity, Hypoblast, and the bilaminar germ disc.

Back 39

The syncytium surrounds a layer of cytotrophoblasts that contains the beginnings of a yoke sac on one side of the embryo while the bilaminar germ disc (that includes the hypoblast and the epiblast) cordon off the amniotic cavity and the amnion that are all pushed distinctly off to one side.

Front 40

[DS Embryology]

The entire fetus will develop from this single layer:

Back 40

epiblast

Front 41

[DS Embryology]

This is a sheet of small cuboidal cells between the epiblast and the blastocele during the bilaminar stage that later becomes the yolk sac.

Back 41

Hypoblast

Front 42

[DS Embryology]

During the bilaminar stage, the hypoblast expands around the periphery of the blastocoel creating this tissue type:

Back 42

extraembryonic endoderm

Front 43

[DS Embryology]

Describe the three layers of the Chorion

Back 43

The chorion consists of the syncytiotrophoblast, the cytotrophoblast, and the Somatic Extraembryonic Mesoderm

Front 44

[DS Embryology]

Describe the Chorionic cavity:

Back 44

The chorionic cavity is the space between the splachnic (inner) extraembryonic mesoderm and the somatic (outer) extraembryonic mesoderm.

Front 45

[DS Embryology]

Describe the splacnic extraembryonic mesoderm:

Back 45

This is an inner layer that surrounds the yolk sac and amnion during the bilaminar stage. It is itself surrounded by the somatic extraembryonic mesoderm layer followed by the syncytiotrophoblast that embeds it within the uterine lining.

Front 46

[DS Embryology]

Describe the somatic extraembryonic mesoderm:

Back 46

This is an outer layer that surrounds a chorionic cavity, then the splacnic extraembryonic mesoderm, then the yolk sac, bilaminar disc, amnion and amniotic cavity.

Front 47

[DS Embryology]

Describe the connecting stalk during the Bilaminar stage:

Back 47

this is a column of extraembryonic mesoderm that connects the splacnic & somatic layers and ultimately develops into the umbilical cord.

Front 48

[DS Embryology]

During what stage does the primitive streak form?

Back 48

Trilaminar stage

Front 49

[DS Embryology]

Describe the Primitive streak:

Back 49

this consists of a primitive groove along with slight elevations on each side called primitive ridges. There is a bulge at the cranial end known as the Hensen's node or the primitive node/knot. This node is the organizer of the cellular changes and processes to come.

Front 50

[DS Embryology]

Describe the process of the primitive streak's elongation & regression during the trilaminar stage.

Back 50

The streak begins at the caudal end and elongates towards the cranial end until it is two-thirds the length of the germ disc. The streak then regresses, ultimately disappearing leaving an independent notochord behind.

Front 51

[DS Embryology]

What are the three layers of the trilaminar germ disc?

Back 51

Ectoderm, Mesoderm, and Endoderm

Front 52

[DS Embryology]

Describe the process of gastrulation:

Back 52

This is the first mass movement of embryonic cells, serving to compartmentalize the embryo into three germ layers. The epiblast cells invaginating through the primitive streak initially creating the endoderm that pushes the previous extraembryonic endoderm out of the way. This space between the newly formed endoderm layer and the Ectoderm layer is filled by Mesodermal mesenchymal cells.

Front 53

[DS Embryology]

Describe the trilaminar endoderm:

Back 53

The endoderms are the first cells to invaginate through the streak wedge into the hypoblast. These cells ultimately grow into the epithelium tissues. (aka Gut)

Front 54

[DS Embryology]

Explain why invagination & spread of mesoderm cells between the epiblast & hypoblast causes multiple embryonic features to develop earlier in the cranial region than the caudal region:

Back 54

The primitive streak progresses from caudal to cranial before regressing back to caudal. This initial progress towards the cranial portion pushes the mesenchymal cells (stem cells) faster into the cranial portion but later these spread throughout. This creates an initial difference in the development preference in the cranial area. The notochord plays the role of organizer here as it secretes morphogens that control differentiation of adjacent tissues.

Front 55

[DS Embryology]

4. Describe how the notochord develops by elongation of Hensen's node, & note the inductive relevance of Hensen's Node and the notochord.

Back 55

Cells that ingress through the Hensen's node do not dissociate, instead they form a hollow tube of contiguous cells known as the notochord that signals the creation & differentiation of nearby cells. wThis stimulates the formation of the neural tube (ultimately the C.N.S.) just above the notochord. The neural groove folds & zips together, the neural tube dissociates, and the ectoderm seals leaving an independent notochord.

Front 56

[DS Embryology]

Discuss the three regions of trilaminar stage mesoderm:

Back 56

The lateral mesoderm develops into the coelem which is the body cavity. One layer of the mesoderm (visceral lateral plate mesoderm) folds in on itself to form the gut tube and connective tissue (messentery). The Somatic portion (parietal lateral plate mesoderm) circles anteriorly to form the thoracic cage and pelvis. The Intermediate Mesoderm develops into the components of the urinary system. The Paraxial mesoderm (somatic) thickens near the midline on each side of the notochord & neural plate to create the sclerotomes, myotomes, and the dermatomes.

Front 57

[DS Embryology]

Explain how the paraxial mesoderm differentiates into somites.

Back 57

The somites differentiate into sclerotomes and dermomyotomes. The sclerotomes eventually develop into the vertebrae while the dermomyotomes split into dermatomes and myotomes to become ultimately dermis and muscle respectively.