9/24 Questions

Question 1

What is a basilar invagination?

Answer 1

the upper cervical spine appears to be invaginated into the skull on x-ray analysis

Question 2

What is the incidence of rib-related changes following dorsalization of C7?

Answer 2

from one-half to two and one-half percent of the population

Question 3

Do patients typically present with symptoms specific for dorsalization of C7?

Answer 3

no, they are typically asymptomatic

Question 4

What is the gender bias suggested in dorsalization of C7?

Answer 4

female

Question 5

What alteration in C7 facet orientation may accompany dorsalization?

Answer 5

superior articular facet of C7 may change from back, upward, medial to that of a typical thoracic facet, back, upward, lateral
The inferior articular facet is unchanged

Question 6

What percent of the population may demonstrate thoracic-like features at C7?

Answer 6

up to 46%

Question 7

What T1 facet orientation changes may accompany cervicalization?

Answer 7

Superior articular facet may change from back, upward, lateral to back, upward, medial
The inferior articular facet is unchanged

Question 8

What is the incidence of cervicalization of T1 in the population?

Answer 8

up to 28% of the population

Question 9

What is the incidence of lumbar ribs in the population?

Answer 9

over 7% of the population demonstrates lumbar ribs

Question 10

What L1 facet orientation changes may accompany dorsalization?

Answer 10

Superior articular facet may change from concave, back, upward, medial to flat, back, upward, lateral
The inferior articular facet is unchanged

Question 11

What is the gender bias associated with dorsalization of L1?

Answer 11

males are two to three times more affected

Question 12

What T12 facet orientation changes may accompany lumbarization?

Answer 12

Superior articular facet may change from flat, back, upward, lateral to concave, back, upward, medial
The inferior articular facet is unchanged

Question 13

What T11 facet orientation changes may accompany lumbarization?

Answer 13

Inferior articular facet may change from flat, forward, medial, downward to convex, forward, lateral, downward
The superior articular facet is unchanged

Question 14

What is the usual way of identifying the number of cervicals, thoracics and lumbar vertebrae during imaging studies?

Answer 14

Identify the vertebrae with ribs-they will be thoracics; those higher are cervicals, those lower are lumbars

Question 15

What is characteristic of lumbarization of S1?

Answer 15

the failure of synostosis between S1 and S2, squaring of the vertebral body of S1 and flaring of the sacral ala

Question 16

What is a basilar impression?

Answer 16

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