Lumbar

Question 1

Degrees of Lumbar Flexion?

Answer 1

40-50 degrees

Question 2

Degrees of Lumbar Extension?

Answer 2

15-20 degrees

Question 3

Degrees of Lumbar Rotation?

Answer 3

5-7 degrees

Question 4

Degrees of Lumbar Side-bending?

Answer 4

20 degrees

Question 5

If a person is flexed forward with a total arc of 85 degrees - how many degrees does the lumbar region account for? the thoracic?

Answer 5

Lumbar: 50 degrees
Thoracic: 35 degrees

Question 6

If a person is extended with a total arc of 35-40 degrees - how many degrees does the lumbar region account for? the thoracic?

Answer 6

Lumbar: 15 degrees
Thoracic: 20-25 degrees

Question 7

If a person laterally bends, with a total arc of 45 degrees - how many degrees does the lumbar region account for? the thoracic?

Answer 7

Lumbar: 20 degrees
Thoracic: 25 degrees

Question 8

If a person is rotated 120 degrees with the head, approximately how many degrees does the craniocervical account for??Thoracic/Lumbar together? Approximately how man degrees of rotation do the thoracic and lumbar region contribute to that portion individually?

Answer 8

Craniovertebral: 80 degrees
T/L: 40 degrees
Lumbar: 5 degrees
Thoracic: 35 degrees

Question 9

Define a disc bulge

Answer 9

Expansion of disc material beyond its normal border (e.g., a normal disc during compression, or a degenerated disc with decreased disc height) – the AF is bulging

Question 10

Define disc protrusion

Answer 10

Discrete localized bulge in the AF, the disc material is displaced (i.e., the NP has protruded through the inner layers of AF) – a true herniation

Question 11

Define disc extrusion

Answer 11

NP has protruded through all layers of AF, but remains attached to disc of origin

Question 12

Define disc sequestrian

Answer 12

free disc fragment is located in the epidural space

Question 13

what motion is required for a disc herniation to occur?

Answer 13

Full Flexion!

Question 14

Describe Rotatores & Intertransversarii regarding...
Motion they contribute to
Cross-Sectional Area
Contribution to rotational torque
Highly rich in what muscular component?
Underlying Function

Answer 14

Axial Rotation
Cross-Sectional Area: Small
Contribution to rotational torque: Minimal
Highly rich in Muscle Spindles (~4-7x more rich than Multifidus)
Underlying function: length transducers or vertebral position sensors at every thoracic and lumbar joint!

Question 15

Longissimus, iliocostalis, and multifidus
Motion that they contribute to?
Thoracic Fiber Type
Lumbar Fiber Type

Answer 15

Extension
Thoracic: 75% slow twitch
Lumbar: Evenly mixed

Question 16

How do the pars thoracis (thoracic portions) of Longissimus, Iliocostalis, and Multifidus attach to the spine?

Answer 16

muscles attach to the ribs and vertebral components
short contractile fibers
long tendons that run parallel to spine

Question 17

Thoracic portion of Longissimus, Iliocostalis, and Multifidus have the _________ amount of extensor moment with __________ compressive penalty to the spine

Answer 17

GREATEST amount of extensor moment with MINIMUM compressive penalty to the spine

Question 18

Lumbar portion of Longissimus, Iliocostalis, and Multifidus generate ________ ________ forces together with extensor moment on _________ vertebrae. The force support any _________ reaction shear forces of the upper vertebrae produced as upper body is flexed.

Answer 18

POSTERIOR SHEAR; SUPERIOR; ANTERIOR

Question 19

Flexion of the torso is accomplished by ______ rotation, not ______ flexion

Answer 19

Hip rotation, not lumbar flexion

Question 20

During flexion, Longissimus, Iliocostalis lose their oblique orientation and reorient to the ________ axis of the spine, so that the flexed spine is unable to resist damaging shear forces

Answer 20

COMPRESSIVE