Exam II Flashcards

1
Q

How are blood vessels named?

A
  • body region they traverse or bone next to them
  • structure that is supplied
  • arteries and veins that travel together are typically named similarly
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2
Q

What is the difference between the systemic and pulmonary systems?

A
  • systemic circulation consists of the blood vessels that extend to and from the body tissues
  • pulmonary circulation consists of the vessels that take the blood to the lungs for gas exchange and then return oxygenated blood to the heart
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3
Q

What are the three main classes of blood vessels?

A

arteries, capillaries, veins

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4
Q

What are anastomoses?

A
  • site where two+ vessels merge to supply the same body region.
  • arterial anastomoses can provide alternate blood supply routes to tissues or organs
  • veins form more anastomoses than arteries
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5
Q

What is the difference between anatomical end arteries and functional end arteries?

A

Anatomical:
-vessels whose terminal branches do not anastomose. zIf those vessels become blocked the tissue will be deprived of oxygen and an infarct develops

Functional:
-anastomoses that are so small that they may be considered end arteries

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6
Q

What are tunics?

A

-these form the wall of the blood vessels and surround the lumen, there are three in blood vessels

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7
Q

What are the three tunics of the vessels and what are their characteristics?

A

tunica intima:
-the inner most layer of of the vessel wall
-composed of simple squamous epithelium aka endothelium
tunica media:
-middle layer of the vessel wall
-composed of circularly arranged layers pf smooth muscle cells under autonomic control (vasodilation nd vasoconstriction)
-arteries have a larger one
tunica externa/adventitia:
-outermost layer
-composed of areolar CT with collagen and elastic fibers and nerve fibers
-helps anchor the vessel to other tissues, protects and supports vessels

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8
Q

What is the vasa vasorum?

A
  • found on the tunica adventitia

- small blood vessels that supply the cells of the vessel wall

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9
Q

What are the differences in structure and function between the veins and arteries?

A

Arteries:
-narrower than vein, wall is thicker than vein, retains circular cross sectional shape, thickest tunic is tunica media, more elastic and collagen fibers than in a vein, bp is higher than in vein, transports blood away from heart to body, system blood is high in O2 and pulmonary is low in O2

Veins:
-wider than artery, though collapsed, thinner than an artery, cross section is flattened and collapsed, thickest tunica is tunica externa, less elastic and collagen fibers, low bp, transports blood from body to heart, ssystemic has blood low in O2 and pulmonary has blood high in O2

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10
Q

What are the three basic types of arteries? How does the diameter change?

A
  • elastic arteries
  • muscular arteries
  • arterioles

-as an artery’s diameter decreases there is a decrease in elastic fibers and increase in smooth muscle

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11
Q

What are some characteristics of elastic arteries?

A
  • conducting arteries, largest diameter
  • thick walled, near heart
  • high proportion of elastic fibers through tunica media
  • dampen bp changes associated with heart contraction
  • passive accommodation results in smooth flow of blood
  • aorta, pulmonary arties, brachiocephalic trunk, common carotid, and iliac
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12
Q

What are some characteristics of muscular arteries?

A
  • medium diameter
  • thick tunica media, more smooth muscle
  • elastic fibers restricted to internal and external elastic lamina
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13
Q

What are some characteristics of arterioles?

A
  • smallest diameter
  • generally less than 6 layers of smooth muscle in tunica media
  • loss of layers with decreasing size
  • under autonomic control -> constriction reduces blood flow and dilation increases blood flow
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14
Q

What are the common arterial disorders?

A

arteriosclerosis- hardening of the arteries
atherosclerosis- fatty deposits and occlusion
hypertension
aneurysm- ballooning and/or rupture of the vessel

-cardiac and cerebral infarct results from the occlusion of the lumen of the arteries causing morbidity

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15
Q

What is atherosclerosis?

A

-slow, complex disease in which fatty deposits/plaque build up in the inner lining of the artery, eventually causing it to narrow and restrict blood flow

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16
Q

What is the response to injury hypothesis?

A

A repeated injury, such as infection or trauma, causes an endothelial inflammation response and that inflammatory response leads to the development of plaques in the arteries

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17
Q

What are some risk factors of atherosclerosis and some treatments?

A

Risk Factors:

  • genetics
  • hypercholesterolemia
  • sex (male)
  • age
  • smoking
  • hypertension

Treatments:

  • angioplasty
  • surgery
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18
Q

What, in general, are capillaries?

A
  • smallest blood vessels that connect arterioles and venules
  • slightly larger than the diameter of an erythrocyte
  • contain only the tunica intima (basement membrane and endothelium)
  • allow gas and nutrient exchange between the blood and the body tissues to occur rapidly
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19
Q

What is the sequence of blood movement through a capillary bed?

A

terminal arteriole -> metarteriole -> pre-capillary sphincter controls blood flow into capillary -> true capillaries -> thoroughfare channel -> capillaries rejoin -> post-capillary venule

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20
Q

What are the three basic kinds of capillaries? And which one is the most common? Which ones are more “leaky?” Where are these capillaries found?

A
  • continuous capillaries (most common): muscle, skin, lungs, CNS
  • fenestrated capillaries (leaky): GI tract, kidney, endocrine glands
  • sinusoids or discontinuous capillaries (leaky): suprarenal glands, spleen, liver, ant pituitary
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21
Q

What, in general, are veins?

A
  • drain capillaries and return the blood to the heart
  • walls are thin and lumen is large
  • systemic carries deoxygenated to the right atrium and pulmonary carry oxygenated blood to the left atrium
  • bp is reduced
  • holds about 60% of body’s blood at rest
  • function as blood reservoirs
  • tunica externa is thickest
  • tunica media has less muscle and more elastin
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22
Q

How do veins prevent pooling of blood?

A
  • valves found in the veins allow for one way flow and prevent backflow
  • assist in moving the blood back to the heart
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23
Q

What is a prominent method utilized to pump the blood back to the heart?

A

Skeletal muscle pump:

-as the skeletal muscles contract, veins are squeezed to help pump the blood toward the heart

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24
Q

What are varicose veins? Risk factors? Treatments?

A

tortuous veins

  • valves are nonfunctional causing blood to pool
  • veins balloon out due to excess of blood sitting in them
  • common in lower limbs
  • genetics, aging, stress (standing, pregnancy, obesity)
  • sclerotherapy: irritant injected into smaller veins to cause scarring and closure
  • vein ablation: heat vein using a catheter until the vein closes
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25
Q

What is deep vein thrombosis? Causes? Treatments?

A
  • blood clot or thrombus, most serious complication is SE
  • common in sural (calf) or femoral (thigh) region
  • causes: pregnancy, “economy class syndrome”
  • treatment: anticoagulant
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26
Q

What is blood pressure measuring? What is hypertension?

A
  • measured in mm Hg, force blood applies to the walls of blood vessels
  • systolic (ventricular contraction, 120)
  • diastolic (during ventricular relaxation, 70)
  • hypertension: chronically elevated bp, 5-10% cases is secondary yo another disease
  • damage to a vessel can cause a thickening of the wall
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27
Q

What is pulmonary circulation?

A
  • system that carries deoxygenated blood from the right side of the heart to the lungs and returns newly oxygenated blood to the left side of the heart
  • blood is pumped into the pulmonary trunk and bifurcates into a left and right pulmonary artery
  • veins carry oxygenated blood and arteries carry deoxygenated blood
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28
Q

What, in general, are blood vessels?

A
  • an efficient mode of transport for oxygen, nutrients, and waste products to and from body tissues
  • heart mechanically pumps blood through the vessels (2 pumps in series)
  • heart and vessels form a closed loop system
  • blood is continuously pumped to the tissues
  • vessels are not rigid and immobile
  • can pulsate and change in shape and course due to bodily needs
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29
Q

Where is arterial supply from the head and neck usually supplied from?

A
  • common carotid (neck, face, ant brain)

- vertebral from subclavian to post brain

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30
Q

Where is the circle of Willis located?

A

-sella turcica

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31
Q

What are the branches of the abdominal aorta?

A
  • to diaphragm (inferior phrenic)
  • GI tract (celiac, sup. and inf. mesenteric)
  • other organs not part of the gut (suprarenal, renal, gonadal)
  • to the body wall (lumbar arteries, analogous to intercostal arteries)
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32
Q

What is the hepatic portal system?

A
  • a venous network that drains the GI tract and shunts the blood to the liver for processing and absorption of transported materials.
  • blood exits the liver through hepatic veins that merge with the inf. vena cava
  • is needed bc the GI tract absorbs digested nutrients, and these nutrients must be processed and/or stored in the liver
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33
Q

What artery is the primary provider of oxygenated blood to the lower limb?

A

internal iliac artery

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34
Q

What are the three sources of blood to the thoracic wall?

A
  • axillary _> supreme thoracic and lateral thoracic
  • subclavian -> internal thoracic/mammory -> ant. intercostal branches
  • aorta -> intercostal arteries
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35
Q

What is CABG?

A

coronary artery bypass graft, typical bypass involves grafting the great saphenous vein or newer procedure involves the left internal thoracic artery

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36
Q

How does aging affect the cardiovascular system?

A
  • heart and blood vessels become less resilient
  • elastic arteries are less able to withstand the forces from the pulsating blood
  • systolic blood pressure may increase with age
  • apt develop an aneurysm and wall is more prone to rupture causing major bleeding and death
  • incidence and severity of atherosclerosis increases
  • skeletal pump system begins breaking down causing edema and varicose veins
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37
Q

What type of epithelium does the neural tube have? Why is this special?

A

pseudostratified columnar

bipotential -> differentiate into either glial or neuronal progenitor cells

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38
Q

What are glial cells responsible for?

A

supporting cells of the CNS. Insulate, nourish, support, and protect neurons

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39
Q

What are the three layers in the developing spinal cord? What cells can be found in each layer?

A

inner most: ventricular- ependymal cells, radial cells, mitotic cells
middle: mantle (gray matter)- young neuron, radial glia, glioblast
outer most: marginal layer (white matter)- neuroepithelial cells, neuron

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40
Q

What do glioblasts differentiate into?

A

astrocytes and oligodendrocytes

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41
Q

How is nerve differentiation in the spinal cord regulated?

A
  1. BMP4 and BMP7 secreted in the ectoderm establish a signaling center in the roof plate
  2. BMP4 in the roof plate upregulated a cascade of TGF-beta proteins, including BMP5 and 7, activin, and dorsalin
  3. SHH from the notochord establishes additional SHH signaling on the floor plate

-overlapping gradient involving the dorsal and ventral factors is established in the neural tube

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42
Q

What are the three types of mesoderm located laterally to the notochord and what will they eventually form?

A

paraxial mesoderm- longitudinal blocks of tissue on either side of the notochord. Gives rise to the axial skeleton and skeletal muscle

intermediate mesoderm- gives rise to urogenital system

lateral plate mesoderm- fives rise to CT and skeleton of the limbs and smooth muscle and CT viscera and blood vessels. NO SKELETAL MUSCLE

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43
Q

What are the segmented blocks of tissue on either side of the notochord called? What type of mesoderm differentiates into it?

A
  • body -> somites
  • head -> somitomeres
  • paraxial mesoderm
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44
Q

Segmentation is controlled by the expression of what gene? What pattern does it follow to create a somite?

A
  • Hox gene

- Hox genes oscillate longitudinally

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45
Q

What is a clock and wavefront model? What is this used for?

A
  • used for creating somites

- peak and fall of Hox genes in different areas of the mesoderm, this shows where a single somite is going to be formed

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46
Q

What protein actually breaks up the blocks of mesoderm? How is this accomplished?

A

-The Notch protein accumulates in presomatic mesoderm destined to form the next somite and then decreases as that somite is established. The increase in Notch activates other segment patterning genes that establish the somite

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47
Q

What controls the boundaries in the somite?

A
  • retinoic acid, FGF8 and WNT3a
  • RA is higher concentration cranially and decrease caudally
  • FGF8 and WNT3a are in higher conc caudally
  • these overlapping expression gradients control the segmentation clock and activity of the Notch pathway
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48
Q

How are creatures that are more segmented develop in terms of number of somites?

A

-the clock component is four times faster in a snake (relative to growth rate) than short bodied animals leading to smaller, shorter somites

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49
Q

What are the three components of a somite?

A

-sclerotome: ventromedial portion closest to notochord, rise to skeleton
-dermamyotome:
+myotome- gives rise to muscles
+dermatome- gives rise to dermis

50
Q

What is resegmentation and where does it take place?

A
  • takes place ONLY in the sclerotome

- rostral and caudal halves of the somite segregate and refuse with neighboring halves to form the vertebrae

51
Q

What forms the nucleus pulposus?

A

notochord

52
Q

How are the vertebra differentiated?

A
  • interaction of different groups of Hox genes
  • Hox 5: cervical
  • Hox 6 and 9: thoracic
  • Hox 10: lumbar, sacral, coccygeal
53
Q

What differentiates the epaxial and hypaxial muscles?

A
  • many regulators, transcription factors myogenic regulatory factors (MyoD, Myf5)
  • epaxial: Pax3, MyoD
  • hypaxial: Myf5
54
Q

Where does the intermediate mesoderm move? What does it form?

A
  • moves to position on posterior abdominal wall
  • forms gonads, ducts, accessory glands or urinary and reproductive tracts

*yolk sac develops the oogonia and spermatogonia

55
Q

What is the lateral plate mesoderm responsible for? How does this generally happen?

A
  • responsible for closing body wall, two separate areas of mesoderm (somatic and splanchnic)
  • splanchnic closes first (forming gut tubes) and somatic lags behind forming body cavity
  • splanchnic is autonomically innervated
56
Q

How is the vertebra formed?

A
  • resegmentation -> nerves slither through the breaks in somites and the caudal portion of the sclerotome fuses with the cranial portion caudal to it
  • originally 8 cervical somites (8 spinal nerves)
  • fusion results in 7 cervical vertebrae
  • cervical spinal nerves exit above vertebra of same number
  • other spinal nerves exit below vertebra
57
Q

What is congenital scoliosis and what are the different types? What is a treatment for scoliosis?

A

-abnormal lateral curvature of the spine, resulting from disruption of normal vertebral development -> result from abnormal formation and segmentation of vertebral precursors
Types:
-hemivertebrae: triangular vertebrae between normally formed ones
-block vertebrae/unsegmented bar: vertebrae fused in strange fashion
-unsegmented bar with hemivertebrae: mix of the two
Treatment:
-surgery
-magnetic bars that can be stretched

58
Q

What is neurofibromatosis?

A

genetic disorder characterized by tumors or neurofibromas that grow in the nervous system and under the skin

59
Q

How are the ribs formed?

A
  • arise from zone of condensed mesenchyme lateral to the body of the vertebra (sclerotome)
  • develop from costal processes, grow into ribs in thoracic region only
  • can develop extra ribs in cervical or thoracic regions
60
Q

How does the sternum develop?

A
  • develops from cartilaginous sternal bars in ventral body wall
  • fuse with one another in cranial-caudal direction
  • forms manubrium, body, and xiphoid process
61
Q

What are the three defects of the sternum discussed in class?

A

pectus carinatum: overgrowth of the cartilage causing the sternum to protrude. Can be evident at birth or during growth spurt (most common). Can occur as solitary congenital abnormality or in association with other genetic disorders.
pectus exacvatum: assumed to be caused by the overgrowth of the costal cartilage. Restricts the expansion of the ribs and pushes the sternum inward. causes unknown, more common in guys.
sternal cleft

62
Q

What is a sternal foramen?

A
  • ossification anomaly found in 4-10% of population
  • can be mistaken for bullet wound
  • common acupuncture point -> directly over heart
63
Q

How is limb growth initiated?

A
  • outgrowth body wall late in week 4, front limbs before hind
  • positioning of the limbs along the craniocaudal axis is regulated by the Hox gene
  • expressed in overlapping patterns from head to tail
  • forelimb: TBX5 and FGF10
  • hindlimb: TBX4 and FGF10
  • secreted by lateral plate mesoderm cells
64
Q

What kind of defects are there when limb development is arrested or never starts?

A
  • meromelia: part of limb isn’t formed
  • amelia: all of limb is missing
  • phocomelia: feet and hands arise close to the trunk
65
Q

What is mesomelia?

A
  • shortened forelimb

- fetal sonograph performed at week 20 demonstrates the typical finding of mesomelic dysplasia

66
Q

What is a radial club hand?

A
  • congenital absence or hypoplasia of the radial structures of the forearm and hand
  • hypoplastic or absent muscular structures and radial nerve
  • treatment is best if early passive stretching exercises and corrective casting is started
67
Q

What is the apical ectodermal ridge?

A
  • runs development and divides and programs cells to differentiate correctly
  • thickened ectoderm on apex of limb bud
  • directs limb bud organization along proximo-distal; axis
  • maintains dorsal/ventral axes
68
Q

Limb development is organized around three axes, what are the three axes?

A
  • apical ectodermal ridge
  • zone of polarizing activity
  • progress zone (mitosis and limb lengthening)
69
Q

How does outgrowth of the limb occur?

A
  • after AER is established, it expressed FGF4 and FGF8, which maintain the progress zone, the rapidly proliferating population of mesenchyme cells adjacent to the ridge
  • distal growth of the limb is then affected by these rapidly proliferating cells under the influence of FGFs
70
Q

What is the zone of polarizing activity in charge of?

A
  • mesodermal cells located at base of limb bud
  • produces retinoic acids which initiates expression of SHH
  • directs organization of limb bud and patterning of digits
  • misexpression of RA or SHH results in a mirror image duplication of the limb structures
  • determines anterior and posterior
71
Q

What are two possible explanations for duplicate defects?

A
  • misexpression of RA a/o SHH

- duplication of AER

72
Q

What is a polydactyl?

A
  • common
  • extra digit that is incompletely formed and useless
  • dominant trait
73
Q

Segmentation of limb bud.

A
  • limb grows and develops proximo-distally
  • zone of cell division/progress zone: region of actively diving cells
  • zone of differentiation: region of cell specialization
74
Q

How is the type of bone in the limb determined and regulated?

A

-Hox genes -> different expression of different bone types determine the formation of the bone

75
Q

What influences the development of distal structures?

A
  • AER secretes FGFs that influence the closest cells (progress zone) to development into distal structures
  • cells no longer within range of AER remain proximal in nature
76
Q

What is thalidomide and what does it cause?

A
  • a teratogen commonly taken for morning sickness, now utilized for leprosy
  • disrupts signaling from AER to progress zone, so babies are born with limb defects (partially formed or not formed limbs)
77
Q

How are the digits formed?

A

APOPTOSIS!!

78
Q

What is a syndactyl?

A
  • most common limb abnormality
  • webbed fingers or toes
  • failure of programmed apoptosis in digital ray
  • simple dominant or recessive inheritance
  • common between 3rd and 4th fingers and 2nd and 3rd toes
79
Q

What is brachydactyly?

A
  • short digits
  • uncommon
  • reduction in the length of phalanges
  • inherited as dominant trait
  • short stature
80
Q

What is a cleft hand or foot?

A
  • uncommon
  • lobster-claw
  • absence of one or more central digits or between digits 2 and 4
81
Q

Where does nervous tissue and muscle derive from?

A
  • hypaxial mesoderm- muscles
  • neural crest: Schwann cells
  • neural tube: motor/sensory axons (dermatome map)
82
Q

How do the limbs rotate?

A
  • upper limbs rotate 90 degrees laterally

- lower limbs rotate 90 degrees medially

83
Q

What is sirenomelia?

A
  • “mermaid syndrome”
  • legs fused together, different severities
  • can be fixed via surgery
84
Q

What is achondroplasia?

A
  • most prevalent form of dwarfism
  • mutation on FGF-R3
  • pathologic changes at epiphyseal plate; zones of proliferation and hypertrophy are narrow and disorganized
  • autosomal dominant
  • failure of proliferation and column formation of epiphyseal cartilage cells (a defect in endochondral bone formation which impairs longitudinal growth of tubular bones)
85
Q

What is osteogenesis imperfecta?

A
  • brittle bone disease
  • bone fragility that predisposes to fractures and deformities related to CT abnormalities
  • blue sclera
  • not always evident at birth
86
Q

What is talipes equinovarus?

A

-club foot
-1/1000 births, two times more frequent in males
-sole if foot is turned medially and inverted
-two types: flexible and rigid
Flexible
-results from abnormal positioning or restricted movement of the lower limbs in utero
-feet are structurally normal
-correct themselves spontaneously
Rigid:
-abnormal development of the ankle and foot joints during the 6th and 7th week
-bone deformities, particularly the talus
Treatment:
-rotate gradually

87
Q

What are the differences between ligaments and tendons?

A

ligaments- connect bone to bone

tendon- connect bone to muscle

88
Q

What are some characteristics of tendons?

A
  • usually have a thick, cordlike structure

- sometimes forms a thin, flattened sheet called an aponeurosis

89
Q

What is the difference between an origin and an insertion?

A

origin- less moveable attachment of a muscle, typically lies proximal to the insertion
insertion- more moveable attachment of the muscle and is toward the origin

90
Q

What are the four organization patterns of muscle fascicles?

A

circular- muscle is also called a sphincter because of the muscle closes off the opening
convergent- muscle has widespread muscle fibers that converge on a common attachment site and are often triangular in shape
parallel- fascicles run parallel to its long axis -> have a central belly or gaster
pennate- have one or more tendons extending through their body, and the fascicles are arranged at an oblique angle to the tendon (most powerful, pack more fascicles per area)

91
Q

What are the definitions for force arm and resistance arm?

A

force arm: distance between axis and point of force

resistance arm: distance between axis and point of resistance application

92
Q

What is the formula used to calculate force and resistance?

A

F * FA = R * RA

93
Q

What are the three classes of levers found in the body?

A

first class: has a fulcrum in the middle, between the force and resistance
second class: resistance between force and fulcrum
third class: force between fulcrum and resistance

94
Q

What is the most common lever in the body?

A

third class

95
Q

What are the skeletal muscle actions?

A

-agonist: prime mover, contracts to produce a particular movement
-antagonist: actions oppose those of the agonist
-synergist: assist the prime mover in performing its action
+the contraction contributes to tension exerted close to the insertion of the muscle or stabilizes the point of origin
+may also assist an agonist by preventing movement at a joint and thereby stabilizing the origin of the agonist
+called fixators

96
Q

What is the vertebral column?

A
  • segmented structure that supports trunk posture, allows trunk movement, transmits the weight of the head, neck, trunk, and upper limb to the lower limb, and protects the spinal cord
  • axial skeleton
97
Q

How many vertebrae are in each “zone?”

A
7 cervical
12 thoracic
5 lumbar
5 sacral
4 coccygeal
98
Q

Where are the curvatures and what are they called?

A
  • cervical lordosis -> secondary
  • thoracic kyphosis -> primary
  • lumbar lordossi -> secondary
  • sacral kyphosis -> primary
99
Q

Characteristics of cervical vertebrae.

A
  • body small and wide side to side
  • spinous process short, bifid, projects posteriorly
  • triangular shaped vertebral foramen
  • transverse process have foramen for vertebral artery
  • movements: flexion and extension, lateral flexion, rotation (greatest range of motion for entire vertebral column)
100
Q

What are the two “oddball” cervical vertebrae? Distinguishing features.

A

ATLAS (C1)
-no centrum, only a tubercle instead of spinous process

AXIS (C2)
-dens (pivot and synovial joint)

101
Q

What are supernumerary ribs?

A
  • extra pair of ribs that arises from C7
  • can result in thoracic outlet syndrome
  • pitchers can develop this with hypertrophied muscles and cut off blood flow
102
Q

What is thoracic outlet syndrome?

A

-an extra rib(s) in the lower cervical region that can cause impingement of the large vessels and nerve (brachial plexus) in this region

Causes include:

  • fractured clavicle
  • extra muscle of scar tissue in scalene muscle area
  • poor posture of the neck and shoulder regions
  • anomalous anatomical variation involving muscles and/or vasculature
  • occur in different areas
103
Q

Characteristics of thoracic vertebrae.

A
  • articulate with ribs
  • looks like a giraffe
  • body is large and heart shaped, costal facets
  • spinous process is long and sharp, project inferiorly
  • circular vertebral foramen
  • transverse facets house facets for ribs
  • movements: rotation, lateral flexion limited, flexion and extension prevented
104
Q

Characteristics of lumbar vertebrae.

A
  • carry majority of weight
  • moose shaped
  • body is large and kidney shaped
  • spinous processes are short and blunt, rectangular shaped and project posteriorly
  • vertebral foramen is triangular in shape
  • transverse process is thin and tapered
  • movements: flexion and extension, some lateral flexion, no rotation
105
Q

Characteristics of sacrum and coccyx.

A
  • composed of 5 fused vertebrae
  • provides strength and stability to the pelvis
  • houses and anchors inferior portion of spinal cord
  • inferior are 3-4 fused vertebrae called the coccyx
106
Q

Herniated disc

A
  • tend to occur in the lumbar region and the herniation typically occurs in the posterior and lateral direction, in part because the posterior longitudinal ligament is not very broad, and the herniated material of the disc will take the path of least resistance.
  • usually a result of wear and tear, disc degeneration
  • sudden and forceful twisting of the midback region
  • abnormal kyphosis (Scheuermann’s disease) predispose individual
  • lumbar bears most of weight
  • frequent bending, twisting, and improper lifting increase tendomns that reinforce region
  • acute or sudden injury
107
Q

What is a stenosis?

A

-bone growth created by inflammation or other reasons

108
Q

What arteries feed each plexus?

A

cervical: vertebral and cervical
thoracic: post intercostal arteries
lumbar: subcostal and lumbar arteries
sacral: iliolumbar, medial and lateral sacral arteries

109
Q

What veins (plexus) discussed in class drain the vertebral column?

A
  • internal vertebral venous plexus
  • external vertebral venous plexus
  • basivertebral veins
  • intervertebral veins
110
Q

Thoracolumnar fascia and supporting muscles

A
  • posterior lamina
  • middle lamina
  • anterior lamina
  • psoas major
  • erector spinae
  • quadratus lumborum
  • transverso-spinal muscles
111
Q

What are some abnormal curvatures of the back?

A
  • kyphosis: abnormal or exaggerated thoracic curve, result from development abnormalities, trauma, or degenerative disease
  • lordosis: abnormal or exaggerated lumbar curvature, result congenital abnormalities, musculoskeletal problems, degenerative disease
  • scoliosis: exaggerated lateral curvature of the spine, can be congenital, neuromuscular, and idiopathic in origin
112
Q

What is spondylolysis?

A
  • broken vertebrae
  • trauma or degenerative disease
  • common cause of spondylolisthesis
113
Q

What is the spinal fracture that looks like a scottie dog?

A
  • located between the inferior and superior articular facets, between the lamina and pedicles of vertebrae
  • fractures at this point associated with spondylolysis
  • fracture is dog’s collar
114
Q

What is spondylolisthesis?

A
  • anterior/ventral displacement of one vertebra on adjacent
  • common progression from spondylolysis, can also be congenital
  • centra slide on one another
115
Q

What is a compression fracture?

A
  • collapse of bone of vertebral body

- can be caused by trauma or degenerative disease

116
Q

What is sacralization?

A
  • fusion or partial fusion of L5 to the sacrum

- congenital

117
Q

Difference between osteopenia and osteoporosis.

A

osteopenia: thinning or decrease in bone mass
- osteoporosis: the condition of having diminished bone density making bones prone to fracture
- degenerative

118
Q

What is a burst or Jeffersonian fracture?

A
  • lateral masses of C1 are compressed between the occipital condyles and the axis (C2), fracturing ant and post arches of C1
  • may also involve rupture of transverse ligament, resulting in dislocation
  • causes include: sudden, forceful compression of C1
119
Q

What is a hangman’s fracture?

A
  • fracture of pars interarticularis (spondylolysis of C2)

- causes include: hyperextension of the neck

120
Q

What is a fracture of the dens?

A
  • fracture at the base of dens (most common) or along body of axis
  • causes include: horizontal blow to the head