Thoracic Spine Biomechanics

Question 1

What type of joint is the sternomanubrial joint?

Answer 1

Symphysis (fibrocartilagenous disc).

Allows for deformation w/ spinal movements and respiration.

Question 2

List the types of sternocostal joints.

Answer 2

I: synarthrosis
2-7: synovial joints with fibrous capsule
8-10: articulate via cartilage of other ribs.
11-12: No lateral attachment.

Question 3

Describe the congruency of the costochondral joints:

Answer 3

Cartilage is convex, rib is concave. Allows for deformation with respiration and spinal movement.

Question 4

Describe the interchondral joints.

Answer 4

Articulation of cartilage from ribs 6-9
Synovial joints
Articulate via interchondral ligaments.

Question 5

Describe the xiphisternal joint type.

Answer 5

Symphysis. Becomes fused after the age of 40.

Question 6

What visceral pain referral patterns correlate with right or left neck and shoulder symptoms?

Answer 6

Right: Liver and Gallbladder
Left: Diaphragm and Lung
- Bc somatic afferents and visceral afferents are in contact and can converge in the spinal cord.

Question 7

What is the orientation of the facet joints in the thoracic spine.

Answer 7

Aligned in the coronal plane.

Question 8

What is the thoracic vertical zone?

Answer 8

Smallest spinal canal (T3-T7, but variable).

Question 9

Where is the apex of thoracic kyphosis?

Answer 9

T7/8.

Question 10

Where is the apex of thoracic kyphosis?

Answer 10

T7/8. Vertebra are higher posteriorly than anteriorly causing kyphosis.

Question 11

How do thoracic discs compare to discs in other regions of the spine?

Answer 11

Thinner and more fibrous.

Question 12

Describe the direction of SP and TP projections in the thoracic spine.

Answer 12

SP direct posteriorly and inferiorly.

TP project posterolaterally.

Question 13

What are the articulation points for the ribs and T/S?

Answer 13

i) body of vertebra has demi facet for head of rib.

ii) TP has articular facet for neck of rib.

Question 14

Describe the orientation and congruency of thoracic facet joints.

Answer 14

i) Apparently for some fucking reason, they’re BOTH concave. OH WAIT NO THEY’RE NOT ACCORDING TO THE NEXT GOD DAMN FUCKING SLIDE. JUST FUCKING WITH ME IS ALL. On Slide 2 then SVIF are concave and IVSF are convex. Opposite the rest of the fucking entire fucking spine because why the fuck not.
ii) Coronally oriented (essentially vertical).

Question 15

What type of joint is the costovertebral joint?

Answer 15

i) synovial, modified ovoid

Question 16

How many articulations does one rib have?

Answer 16

i) Most ribs articulate with the vertebrae at its level as well as the one above via the radiate ligament.
i) The ribs may also articulate with the disc.
ii) Ribs 1, and 10-12 only articulate with one rib.

Question 17

What type of joint is the costotransverse joint? Describe the congruency.

Answer 17

i) synovial, modified ovoid.
ii) Between the tubercle of the rib and the anterior articulating process of the vertebra at the same level.
iii) Ribs 1-6 are convex and the TP is concave. Ribs 7-12 are planar.

Question 18

What is the resting position of the z-joints in the the thoracic spine?

Answer 18

Slight flexion.

Question 19

What is the close packed position of the z-joints in the T/S?

Answer 19

Full extension.

Question 20

What is the capsular pattern of the T/S?

Answer 20

SF = rot’n > extension

Question 21

Which direction do the facets face in the thoracic spine?

Answer 21

SVIF (concave) anteriorly, inferiorly and medially.

IVSF (convex) posteriorly, superiorly and laterally.

Question 22

Describe the osteokinematics and arthrokinematics of T/S flexion.

Answer 22

i) anterior rotation, anterior translation (30’-40’)

ii) SVIF slides superiorly and anteriorly.

Question 23

Describe the osteokinematics and arthrokinematics of T/S extension.

Answer 23

i) posterior rotation (20’-25’), posterior translation.

ii) SVIF slides posteroinferiorly.

Question 24

Describe the osteokinematics and arthrokinematics of side flexion in the T/S.

Answer 24

i) rotation in the coronal plane (25’).
ii) ipsilateral translation.
iii) contralateral rotation.
Note: contralateral coupling only happens at the end range of segments ROM.