Flashcards in Transition Zones Deck (40)
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1
What is/are the characteristics of occipitalization of C1?
the atlas may be partially or completely fused to the occiput
2
What is another way of implying occipitalization of C1?
atlas assimilation
3
What is the incidence of occipitalization of C1?
0.1% to 0.8%
4
When do the centers of ossification for the odontoid process first appear?
during the last trimester in utero
5
When do the bilateral ossification centers for the odontoid process fuse?
at or shortly after birth
6
What joint is formed between the odontoid process ossification centers and the centrum of C2?
the subdental synchondrosis
7
What is the classification of the joint formed between the C2 odontoid process and centrum?
amphiarthrosis synchondrosis
8
Ossification between the odontoid process and centrum joint of C2 first appears at what age?
4 years old
9
A joint between the odontoid process and centrum of C2 is last identified at what age?
7 years old
10
What is the name given to the condition in which the joint formed between the odontoid process and centrum of C2 persists beyond age 7?
os odontium
11
What is the name given to the joint between the odontoid process and centrum of C2 which is still evident beyond age 7?
persistent subdental synchondrosis
12
What is the name given to the joint formed between the tip of the dens and odontoid process centers of ossification?
tip of the dens synchondrosis
13
What is the classification of the joint formed between the tip of the dens and the odonotoid process center of ossification?
amphiarthrosis synchondrosis
14
At what age will the tip of the dens center of ossification appear?
sometime in early adolescence
15
Based on the age of appearance, how is the tip of the dens center of ossification classified?
secondary center of ossification
16
At what age will the tip of the dens fuse with the odontoid process?
before age 12
17
If the joint formed between the tip of the dens and odontoid process centers of ossification persists beyond age 12, what is the condition called?
terminal ossicle
18
What is a basilar impression?
persistence of the nonunion of the basilar and condylar parts of the chondrocranium such that the cartilage deforms due to the weight of the brain
19
What is the basilar invagination?
the upper cervical spine appears to be invaginated into the skull on x-ray analysis
20
What is the incidence of rib-related changes following dorsalization of C7?
From one-half to two and one-half percent of the population
21
Do patients typically present with symptoms specific for dorsalization of C7?
no, they are typically asymptomatic
22
What is the gender bias suggested for dorsalization of C7?
female
23
What alteration in C7 facet orientation may accompany dorsalization?
the superior articular facet of C7 may change from back, upward, and medial (BUM) to that of a typical thoracic facet...back, upward, and lateral (BUL); the inferior articular facet is unchanged
24
What alteration in C6 facet orientation may accompany dorsalization?
C6 demonstrates a change in inferior articular facet orientation from forward, lateral, and downward (FoLD) to forward, medial and downward (ForMeD); the superior articular facet is unchanged
25
What percent of the population may demonstrate thoracic-like features at C7?
up to 46%
26
What rib-related changes may accompany cervicalization of T1?
the first rib may decrease in mean relative length or become absent
27
What is the incidence of cervicalization of T1 in the population?
up to 28% of the population
28
What is the incidence of lumbar ribs in the population?
over 7% of the population demonstrates lumbar ribs
29
What T12 face orientation changes may accompany dorsalization?
the inferior articular facet may change from convex, forward, lateral, and downward (FoLD) to flat, forward, medial, and downward (ForMeD); the superior articular facet is unchanged
30
