Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

MSKI Final Exam material > Dr. Cole's Development of the Skeletal System > Flashcards

Dr. Cole's Development of the Skeletal System Flashcards

1
Q

What are vertebrae derived from?

A

sclerotomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Sclerotomes do what in the formation of vertebrae?

A

They split into caudal and cranial sections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What parts of the developing vertebrae fuse, and from what?

A

Sclerotomes divide into cranial and caudal parts, and the cranial parts fuse with the caudal part from the sclerotome adjacent to it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

During vertebrae development, what is happening with spinal nerves?

A

they are growing out between the newly forming vertebrae and merging with myotomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain why there are 8 somites originally in the cervical region but only 7 cervical vertebrae

A

the sclerotomes divide and fuse: somite number 8 divides into the caudal portion of C7 and the cranial portion of T1, which means explains why.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do cervical spinal nerves exit?

A

they exit above their respective vertebrae of the same number while the other spinal nerves exit below vertebrae

spinal nerve root C8 grows between C7 and T1, this explains the ratio of spinal nerves to vertebral segments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Sclerotomes form two things, and the notochord develops into something as well

A

Sclerotomes form neural arches around developing spinal cord and form the centrum as well
the notochord regresses and is incorporated into the intervertebral disc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Herniated intervertebral disc

A

the nucleus pulposeous herniates outward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Congenital scoliosis: 3 kinds

A

A) SEMISEGMENTED: failure of formation (there is a single wedge like vertebrae causing others to be decentered that did not form correctly)

B) BLOCK VERTEBRAE and UNSEGMENTED BAR: failure of segmentation

C) MIXED (unsegmented and semi-formed)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the “basic” cause of scoliosis?

A

abnormal formation of segmentation of somites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

a treatment for scoliosis?

A

magnetic rods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Formation of ribs:

from where do they arise, and what region?

A

arise from zones of condensed mesenchyma lateral to the vertebra FROM costal processes

develop in thoracic region only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Development of Sternum:

develops from…
fuses how…
forms….

A

develops from cartilaginous sternal bars in ventral bony wall

fuses with one another in cranial caudal direction (top down)

forms the manubrium, body and xiphoid process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pectus excavatum

A

costal cartilage overgrowth, which restricts expansion of the ribs and pushes sterum inward. largely males.

cause is truly unknown

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Pectus carinatum

A

overgrowth of cartilage causing sternum to protrude

can be evident at birth, but mostly visible at adolescents

can occur solitary or in association with other genetic disorders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Sternal Foramen

A

Ossification anomaly found in 4-10% of population
CAN BE MISTAKEN FOR A BULLET HOLE!
Directly over heart
Common area for acupuncture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Appendicular skeleton development (general big picture things)

A

1) Hox gene expression
2) Inductive interactions between mesoderm and ectoderm
3) mechanical influences

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Initiation of limb development occur what week, occurs along what axis, and is regulated by what genes?

A

4th wk, craniocaudal axis, Hox genes (overlapping patterns from head to tail

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what axis is established first in limb development?

A

cranial-caudal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Cranialcaudal axis is established ____, growth is then regulated along the….axises

A

proximodistal, anteroposterior, dorsoventral axes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Forelimb outgrowth is initiated by

A

TBX5 and FGF10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Hindlimb outgrowth is initiated by

A

TBX4 and FGF10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

TBX5, TBX4, and FGF10: which is hindlimb and which is forelimb

A

TBX5/FGF10 –> forelimb
TBX4/FGF10–> hindlimb

both development from lateral plate mesoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Holt Oram syndrome

A

mutation in the TBX5
important in development of both upper limbs and heart

upper limb abnormalities always present

abnormalities may be unilateral or bilateral and asymmetric

MOST PREVALENT FINDINGS ARE FUSED CARPALS or MALFORMATIONs of carpals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Holt Oram abnormalities may effect which bones of the upper limbs?
thenar, radial, ulnar bones most prevalent findings are malformations or fusions of the carpal bones
26
Holt Oram: meromelia amelia phocomelia
Meromelia: partial abnormality, some development Amelia: total non-development (all limb is missing) Phocomelia: feet an hands arise close to trunk
27
AER
Apical Ectodermal Ridge thickening ectoderm on apex of limb bud
28
Formation of the AER
Once limb outgrowth is established, BMPs induce formation of aplical ectodermal ridge
29
Radical Fringe: location of expression and function
expressed in the dorsal half of limb ectoderm | restricts location of the AER to the distal top of the limbs
30
RF: expresses what and where
SER2 at border between cells between RF expressing cells and non-RF expressing cells this is where AER is formed
31
Engrailed-1
represses expression of RF in ventral ectoderm cells
32
3 axes of limb development
Anterior-Post: Proximal-Distal: Dorsal-Ventral
33
When 3 axes are visible, what two areas control/regulate growth?
AER, ZPA, PZ
34
PZ
progress zone where mitosis and limb lengthening occurs
35
AER direct limb growth along
proximo-distal axis
36
AER maintains
dorsal/ventral axis
37
After AER is established, is expresses
FGF4 and FGF8
38
What do FGF4 and FGF8 do?
maintains the progress zone, which are rapidly proliferating population of mesenchyme cells adjacent to the ridge
39
FGF4/FGF8
maintains progress zone affects distal growth of the limb
40
FGF4/8 leads to
distal growth of the limb bud
41
ZPA
zone of polarizing activity mesodermal cells located at base of the limb which produces retinoic acid which expresses Shh
42
RA leads to expression of ___ in the ZPA
Shh
43
ZPA directs
organization of limb bud and patterns of digits
44
Misexpression of RA or Shh results in
miror image reduplication of the limb structures
45
ZPA determines what?
Pre-axial/thumb and Posterior (postaxial)
46
misexpression of RA and Shh cause what?
polydactyly and duplication of AER
47
In Polydactyly, what is most commonly the case of the extra digit?
that it is located either medial or later non-functional in foot, usually lateral dominant trait
48
a limb grows
proximo-distally
49
segmentation of the limb buds: what two zones are there
the Zone of Cell division (progress zone): region of actively dividing cells) the Zone of Differentiation: region of cell specialization
50
What is the relation of Hox genes to bones?
they regulate type and shape of bones
51
AER secrete ____ that cells in the _____ to
FGFs, progress zone, distal structures
52
What happens if a cell is not within range of the AER?
it remains proximal in nature
53
Progress zone and FGF signaling and Thalidomide Phocomelia
FGF secreted by AER causes cells in PZ to proliferation; thalidomide disrupts this. So limb is developing but there is no growth. FGF re-specifies in PZ to become later and later distal components
54
Digit formation
apoptosis of webbing cells allows for digits to develop
55
syndactyly
failure of apoptosis, so digits are fused
56
Where does cell death in digit formation occur?
in the AE: creates a separate ridge for each digit
57
what is the most common limb abnormality?
syndactyly, most commonly between 3rd/4th finger and 2/3rd toes simple dominant or simple recessive
58
Brachydactyly
short digits uncommon, reduction in the length of the phalanges inherited as dominant trait short stature
59
Cleft hand/foot
uncommon, lobster claw | absence of one or more central digits or between fingers 2 & 4
60
Lateral plate mesoderm =
skeleton and vasculature
61
Hypaxial mesoderm =
muscles
62
Neural crest -
Schwann cells
63
Neural tube =
motor neurons/sensory axons (dermatome map)
64
Developing Dorsal ramus ramify through
epimeres
65
Developing ventral ramus ramify through
hypomeres
66
brachial plexus processes ramify through two regions that are split by a third region: name them
posterior process --> posterior condensation anterior process --> anterior condensation divides by lateral plate mesoderm
67
what degrees do the upper and lower limbs rotate?
90 degrees | some dorsal musculature lags behind and comes to lie on the anterior/pre-axial border (explains brachioradialis)
68
Sirenomelia
"mermaid syndrome" legs are fused
69
Congenital limb anomalies are mostly
of unknown etiology , probably multifactorial between genetics and environment complex interactive nature of limb development
70
Separation Surgery of sirenomelia (4 steps)
1) legs are fused together by skin; feet splayed in V shape 2) saline sacks progressively inserted to stretch skin 3) two operations, 3 months apart, separate the legs then use the stretched skin to cover wounds 4) last operation will rotate splayed feet forward
71
Achondroplasia
most prevalent form of dwarfism mutation on FGF-R3 pathologic changes at epiphyseal plate; zones of proliferation and hypetrophy are narrow and disorganized
72
Achondroplasia genetics and causes
autosomal dominant failure of proliferation failure of column formation of epiphyseal cartilage cells impairment causes lack of tubular bones to grow
73
Osteogenesis Imperfecta
also known as brittle bone disease bone fragility that predisposes individual to deformities related to connective tissue abnormalities blue sclera not always evident at birth
74
Talipes Equinovarus
Club foot talipes equinovarus is the most common type of club foot sole of foot is turned medially and foot is inverted
75
Club foot
results from restricted movement of lower limbs in utero or abnormal position of fetus
76
What do the feet look like in club foot?
normal, feet are normal appearing
77
Feet are structurally ___ in club foot
normal
78
Rigid club foot
abnormal development of the ankle and foot joints during 6th/7th week
79
what bony deformity is particularly common in club foot?
talus
80
Axial skeleton is formed from
sclerotomes of the somite
81
appendicular skeleton is formed from
somatic lateral plate mesoderm
82
limb musculature develops from
hypaxial mesoderm

MSKI Final Exam material (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions