C1 (Quiz 2/ Test 2)

Question 1

What is the most atypical vertebra of the spine?

Answer 1

C1

Question 2

Why is C1 atypical?

Answer 2

-no body
-no SP
-no pre/post-zygopophyses
-has lateral masses
-has anterior and posterior arches
-it is a pentagonal ring embedded within a diamond shape

Question 3

What is the main bulk of C1?

Answer 3

lateral masses

Question 4

What structure on C1 supports and transmits weight of the head onto C2?

Answer 4

lateral masses

Question 5

What are the lateral masses homologous to?

Answer 5

articular pillars

Question 6

The superior articular surfaces of C1 cover the entire top of…

Answer 6

each lateral mass

Question 7

What do the superior articular surfaces of C1 articulate with?

Answer 7

occipital condyles above

Question 8

The superior articular surfaces of C1 match what other surfaces?

Answer 8

condylar surfaces

Question 9

What shape are the superior articular surfaces of C1?

Answer 9

kidney shaped, smooth, and concave (large axes converge anteriorly)

Question 10

What direction do the superior articular surfaces of C1 face?

test q

Answer 10

superomedially

Question 11

The superior articular surfaces of C1 may show a sulcus. What is this the result of?

Answer 11

subcortical vessel

Question 12

The inferior articular surfaces of C1 cover the entire bottom of….

Answer 12

each lateral mass

Question 13

What do the inferior articular surfaces of C1 articulate with?

Answer 13

C2 superior articular surfaces

Question 14

What shape are the inferior articular surfaces of C1?

Answer 14

round/ oval (long axes converge anteriorly)

Question 15

What direction do the inferior articular surfaces of C1 face?

test q

Answer 15

inferomedially (from a wedge with the superior articular surfaces)

Question 16

What are the inferior articular surfaces of C1 covered with?

Answer 16

thick cartilage (actual joint surfaces are convex)

Question 17

What tubercle is found on the lateral masses? Where does it project?

Answer 17

medial atlantal tubercle
-distinct round bump on the medial surface of each lateral mass
-projects into the neural foramen

Question 18

What is homologous to the medial atlantal tubercles on the lateral masses of C1?

test q

Answer 18

the medial condylar tubercle

Question 19

What part of the lateral masses on C1 is an attachment for the transverse ligament?

Answer 19

medial atlantal tubercle

Question 20

What is the only typical portion of C1?

Answer 20

TPs

Question 21

Which cervical vertebra has the longest TPs?

Answer 21

C1

Question 22

What are the 3 parts of C1 TPs?

Answer 22

1) anterior false costo
2) posterior true
3) distal transverse tubercle

Question 23

Where do the anterior false costo part of TPs of C1 project?

Answer 23

Postero-infero laterally

Question 24

Where do the posterior true parts of the TPs of C1 project?

Answer 24

antero-supero laterally

Question 25

What 2 parts of the TPs of C1 fuse distally? Where do they end/what is it called?

Answer 25

Anterior and posterior parts of TPs of C1 fuse distally They end in a large knobby transverse tubercle

Question 26

Do the TPs of C1 have a costo-transverse lamella?

Answer 26

No

Question 27

What is the biggest hole in C1 called? What flows through it?

Answer 27

Foramina transversaria -vertebral arteries slide in/out during rotation -blood flow may be temporarily occluded ipsilaterally -prominent lever arms for lateral flexion and rotation

Question 28

What structure joins the lateral masses of C1 anteromedially?

Answer 28

Anterior arch (straight or slightly convex bony bridge)

Question 29

What is the anterior arch of C1 homologous to?

Answer 29

Fused pedicles (C1 minus body)

Question 30

What structure on C1 is the attachment for the longus cervicus muscle and anterior ligaments? Test q

Answer 30

Anterior tubercle (low rounded bump on the anterior midline)

Question 31

What is the fovea dentalis of C1?

Answer 31

-concave, oval articular facet -smooth, raised margins -posterior median aspect of the anterior arch

Question 32

What does the fovea dentalis of C1 articulate with?

Answer 32

The anterior dens

Question 33

What structure on C1 joins the lateral masses posteromedially?

Answer 33

Posterior arch

Question 34

Is the posterior arch considered one structure or two?

Answer 34

1 structure with L/R sides

Question 35

What is the posterior arch of C1 homologous to? Test q

Answer 35

The laminae

Question 36

What is the posterior tubercle of C1?

Answer 36

-low rounded bump on the posterior midline -rudimentary SP -often slightly bifid

Question 37

What are the superior vertebral/neural grooves (L/R) of C1? What do they help form?

Answer 37

-shallow/flat superior depressions -just behind lateral masses -help form the 1st IVFs

Question 38

What enters and exits the superior vertebral/neural grooves (L/R) of C1?

Answer 38

-vertebral arteries enter anteriorly -C1 spinal nerves exit posteriorly

Question 39

What is the inferior vertebral/neural notches (L/R) of C1? What do they form?

Answer 39

-deeper inferior depression -just behind lateral masses -help form 2nd IVFs (C2 spinal nerve exits here)

Question 40

What is the neural foramen? What are its 2 parts and what are the contents in each part?

Answer 40

-looks like foramen magnum -larger posterior neural portion contains the spinal cord -smaller anterior odontoid portion contains the dens