Cervical Biomechanics

Question 1

What is the normal lordosis of the cervical spine?

Answer 1

30-35 degrees

Question 2

With cervical flexion how much flexion comes from the atlanto-occipital joint? Atlanto-axial joint? Lower cervical vertebrae? How much combined?

Answer 2

OA-5 degrees

AA-5 degrees

Lower Cervical- 35-40 degrees

combined-40-50 deg

Question 3

With cervical extension how much extension comes from the atlanto-occipital joint? Atlanto-axial joint? Lower cervical vertebrae? How much combined?

Answer 3

OA- 10 degrees

AA-10 deg.

Lower Cervical-55-60 deg

combined-70-80 deg

Question 4

With cervical rotation how much rotation comes from the atlanto-occipital joint? Atlanto-axial joint? Lower cervical vertebrae? Combined?

Answer 4

OA-none

AA- 35-40 deg

Lower Cervical- 30-35 deg

combined-65-75 deg

Question 5

With cervical sidebend how much sidebend comes from the atlanto-occipital joint? Atlanto-axial joint? Lower cervical vertebrae? combined?

Answer 5

OA- 5 degrees

AA-none

Lower Cervical- 30-35 deg.

combined- 35-40 deg

Question 6

What is a type 1 mechanic of the cervical spine? Where do they occur?

Answer 6

When rotation and sidebend occur in the opposite directions

upper cervical spine

Question 7

What is a type 2 mechanic of the cervical spine? Where does this occur mostly?

Answer 7

Rotation and sidebend occur to the same side

lower cervical spine

Question 8

What is a type 3 mechanic of the cervical spine? What is an example

Answer 8

when motion in 1 plane reduces motion in all remaining planes

example: when head is fully flexed it limits all other motions

Question 9

What are the flexion and extension arthrokinematic motions of the Atlanto-occipital joint?

Answer 9

(occiput is convex while C1 superior body is concave)

Flexion- occipital condyles roll anterior and glide posterior

Extension-occipital condyles roll posterior and glide anterior

Question 10

What limits the shaking or “no” movement of the atlanto-axial joint?

Answer 10

alar ligaments, apophyseal joint tension, and muscles

Question 11

What are the 3 main upper cervical ligaments and what are their functions?

Answer 11

Alar ligament- stabilizes occiput-atlas w/ rotation

Transverse lig.- prevents anterior migration C1 on C2

Tectorial Membrane

Question 12

As the lower cervical spine rotates, which way does the spine normally laterally flex?

Answer 12

To the same side as the rotation

Question 13

In the lower cervical spine, as you extend your spine which way do the vertebrae slide? How does this change with flexion?

Answer 13

The vertebrae slide posterior/inferior with extension and slide anterior/superior with flexion