Muscles Of The Lumbar Spine

Question 1

What is the origin of the internal abdominal obliques?

Answer 1

Iliac crest, thoracolumbar fascia

Question 2

What is the insertion of the internal abdominal obliques?

Answer 2

Inferior borders of ribs 10-12, linea alba, pectin pubis

Question 3

What is the action of the internal abdominal obliques?

Answer 3

Bilateral contraction= expiration. Trunk flexion
Unilateral contraction= trunk lateral flexion to same side, trunk rotation to same side

Question 4

What is the origin of the external abdominal oblique?

Answer 4

External surfaces of ribs 5-12

Question 5

What is the insertion of the external abdominal obliques?

Answer 5

anterior half of Iliac crest, linea alba, pubic tubercle, ASIS

Question 6

What is the action of the external abdominal obliques?

Answer 6

Bilateral contraction= expiration, trunk flexion
Unilateral contraction= trunk rotation to opposite side and lateral flexion to same side

Question 7

What is the origin of the Rectus abdominis?

Answer 7

Pubic symphysis, pubic crest

Question 8

What is the insertion of the Rectus abdominis?

Answer 8

Xiphoid process, costal cartilages of ribs 5-7

Question 9

What is the action of the Rectus abdominis?

Answer 9

Trunk flexion, expiration, compresses abdominal viscera

Question 10

What is the origin of the transversus abdominis?

Answer 10

Costal cartilages of ribs 7-12, thoracolumbar fascia, iliac crest, iliopectineal arch

Question 11

What is the insertion of the transversus abdominis?

Answer 11

Pecten pubis, pubic crest, linea alba

Question 12

What is the action of the transversus abdominis?

Answer 12

Bilateral contraction= compresses abdominal viscera, expiration
Unilateral contraction= trunk rotation to same side

Question 13

What is the origin of the Multifidus?

Answer 13

Superior articular processes of C4-C7, transverse processes of all thoracic vertebra, mammillary process of lumbar vertebra, posterior aspect of sacrum, PSIS

Question 14

What is the insertion of the Multifidus?

Answer 14

Lateral aspect of spinous processes of vertebrae 2-5 levels above origin

Question 15

What is the action of the Multifidus?

Answer 15

Bilateral contraction= trunk extension
Unilateral contraction= trunk rotation to opposite side and lateral flexion to same side

Question 16

What is the origin of the quadratus lumborum?

Answer 16

Iliac crest, iliolumbar ligament

Question 17

What is the insertion of the quadratus lumborum?

Answer 17

Rib 12, transverse process of L1-L4

Question 18

What is the action of the quadratus lumborum?

Answer 18

Bilateral contraction- Flexes rib 12 in inspiration, trunk extension
Unilateral contraction- trunk lateral flexion to same side

Question 19

What is the origin of the erector spinae?

Answer 19

9 separate muscles that generally originate from lumbar and lower thoracic regions

Question 20

What is the insertion of the erector spinae?

Answer 20

Generally insert into the upper thoracic and cervical regions

Question 21

What is the action of the erector spinae?

Answer 21

Bilateral contraction= extension of spine
Unilateral contraction= lateral flexion of spine to same side