Cervical Bio-mechanics

Question 1

How is cervical motion permitted?

Answer 1

By the shape of the bone and the characteristics of the discs

Question 2

How is cervical motion guided?

Answer 2

By the joint facets

Question 3

How is cervical motion restrained?

Answer 3

By the ligaments

Question 4

How is cervical motion produced?

Answer 4

By the musculature

Question 5

What are some motion segments for the cervical region?

Answer 5

Occipito-Atlantal Motion segment
Atlanto-Axial Motion segment
C2 to C6 Motion segments
C7 Motion Segment

Question 6

What do the short sentimental muscles do in the cervical region?

Answer 6

The stabilize the spine

Involuntary and adapt the spine to motion and balance

Question 7

What do the short segmental muscles do in terms of dysfunction?

Answer 7

Most commonly produce and maintain segmental dysfunction

Question 8

What are the two types of cervical motion?

Answer 8

Major motion and free play motion

Question 9

What are the major motions of the occipito atlantal joint?

Answer 9

Flexion and extension at 20 degrees (nutation)

Question 10

What are the minor motions of the occipito atlantal joint?

Answer 10

Sidebending at 5 degree bilaterally

Rotation at 3 to 8 degrees bilaterally

Question 11

What kind of dysfunctions can the occipito atlantal joint have?

Answer 11

It can be flexed for extended, sidebending and rotation are usually opposite with type 1 like mechanics
Rarely neutral

Question 12

What are the potential dysfunctions of the occipito atlantal joint (named)?

Answer 12

OA-FRRSL
OA-FRLSR
OA-ERRSL
OA-ERLSR
OA-Compressed (Uncommon)

Question 13

What is the primary motion of the atlanto-axial joint?

Answer 13

Rotation at 40 degrees bilaterally

Question 14

What is the freeplay motion of the atlanto-axial joint?

Answer 14

Flexion and extension at 20 degress

Sidebening at 5 degrees bilaterally

Question 15

Where does most cervical rotation occur?

Answer 15

Between the occiput and C2 (C1/C2) at 60%

Question 16

If there is a dysfunction with OA and C1 how can you correct both?

Answer 16

Usually if you fix the OA dysfunction the C1 gets corrected too

Question 17

What does the sternocleidomastoid do?

Answer 17

Sidebends towards and rotates away

Question 18

What do the scalene muscles do?

Answer 18

Sidebend and rotate toward

Question 19

What is the origin and insertion of splenius capitis?

Answer 19

Spines of C3 to T3

Mastoid portion of the temporal bone

Question 20

What is the origin and insertion of splenius cervicis?

Answer 20

Spines of T3 to T6

Transverse processes of C1 to C3

Question 21

What is the origin and insertion of semispinalis capitis?

Answer 21

Transverse processes of C4 to T7

Occiput

Question 22

What is the origin and insertion of semispinalis cervicis?

Answer 22

Spinous process of C2 to C5

Transverse process of T1 to T6

Question 23

What is the origin and insertion of semispinalis thoracis?

Answer 23

Spinous processes C6 to T4

Transverse process of T6 to T10

Question 24

What happens if the spine is stripped of its musculature?

Answer 24

It can only support a gead weighing less than 4.4 pounds (a normal head weight 10-12 pounds)

Question 25

What is the motion of the C2 to C7 controlled by? How is the motion coupled?

Answer 25

Facet joint orientation | Sidebending and rotation are coupled to the same side

Question 26

Which vertebrae have type 2 like mechanics?

Answer 26

C2 to C6

Question 27

Where is the largestest range of motion between C2 and C7 for flexion and extension?

Answer 27

C4-C5 and C5-C6 at 20 degrees

Question 28

What are some potential dysfunctions for C2 to C6?

Answer 28

``` FRrSr -- FRSr NRrSr -- NRSr ERrSr -- ERSr FRlSl -- FRSl NRlSl -- NRSl ERlSl – ERSl ```

Question 29

What type of mechanics does C7 follow?

Answer 29

Typical Fryette type 1 mechanics

Question 30

What is the order for treating multiple segments?

Answer 30

Occipito-atlantal (OA or C-0) C7 & T1 C2 through C6 Atlanto-axial (C-1)

Question 31

What happens to intervertebral discs when load increases?

Answer 31

Increased stability due to alternating fibers of the annular layer causing increased stiffness

Question 32

What happens when two vertebrae and their intervening disc are subjected to vertical load?

Answer 32

The first tissue to fail is the bone with fracturing of the vertebral endplates

Question 33

In terms of degrees, where is the disc the stiffest?

Answer 33

15 degrees

Question 34

What is the normal motion for a disc?

Answer 34

They bulge toward the direction of motion and flatten on the opposite side

Question 35

What is the motion of a disc in degenerative disc diesase?

Answer 35

They bulge away from the direction of motion and flatten on the same side

Question 36

At what value do lumbar discs fail?

Answer 36

5300 newtons

Question 37

At what value do cervical discs fail?

Answer 37

75 newtons