Back Muscles

Question 1

What does the back do?

Answer 1

Provides attachment site for muscles from different parts of the body.

Question 2

Give examples of parts of the body which get muscle attachment at the back.

Answer 2

-Head
* Upper limb
* Thorax
* Abdomen
* Hips
* Lower limbs

Question 3

Name the two groups of back muscles.

Answer 3

Intrinsic and Extrinsic

Question 4

What do the extrinsic back muscles assist with?

Answer 4

• Upper limb movement and respiration (movement of the chest wall)

Question 5

Name the three layers of intrinsic back muscles.

Answer 5

Superficial
Intermediate
Deep

Question 6

What do intrinsic back muscles do?

Answer 6

• Maintain posture
• Control movement of the vertebral column

Question 7

What do muscles attached from the front of the vertebral column do?

Are these muscles bilateral or unilateral?

Answer 7

Cause flexion of the vertebral column.

Bilateral

Question 8

What do muscles attached from the back of the vertebral column do?

Are these muscles bilateral or unilateral?

Answer 8

Cause extension of the vertebral column.

Bilateral

Question 9

What other movements can be caused by unilateral back muscles?

Answer 9

Rotation
Lateral flexion

Question 10

Muscles with oblique fibre orientation assist with?

Answer 10

Rotation

Are unilateral.

Question 11

Which muscles are anterior to the spine and can therefore assist with flexion?

Answer 11

Rectus abdominis and psaos Major (front muscles)

Question 12

Which muscles are posterior to the spine and can therefore assist with extension?

Answer 12

Erector Spinae (back muscle)

Question 13

Which muscles have oblique fibre orientation an can therefore assits with rotation?

Answer 13

External oblique, internal oblique
(opposite side), and erector spinae

Question 14

Which muscles can assist with lateral flexion?

Answer 14

– Erector Spinae, external and internal oblique

Question 15

What are the 3 large and flat muscles with different fibre orientation found in the anterior abdominal walls and Rectus abdominis?

Answer 15

Internal oblique muscle
External oblique muscle
Transversus abdominis

Question 16

Describe the direction of the fibres in each of the following-
Internal oblique muscle
External oblique muscle
Transversus abdominis

Answer 16

Internal oblique muscle- steeply upwards, in pocket direction
External oblique muscle- horizontal direction to the spine.
Transversus abdominis- horizontally

Question 17

What are the three large flat muscles associated with in terms of movement?

Answer 17

Anterior flexion, lateral flexion & rotation of the trunk

Question 18

Name the posterior abdominal wall muscles

Answer 18

Illiacus
Psoas major
Quadratus lumborum

Question 19

What does Iliopsoas help with?

Answer 19

Forward bending or flexion

Question 20

What does Quadratus lumborum help with?

Answer 20

Lateral flexion

Question 21

What does the erector spinae do?

Answer 21

-Is intrinsic muscle

*Extension of vertebral column(bilaterally)
* Lateral flexion of vertebral column (unilaterally)

Question 22

What happens to intervertebral discs when aging occurs?

Answer 22

Become dehydrated so loses some of their shock absorption.
Becomes thinner.

Water conc decreases and collagen conc increases

Question 23

Describe osteoporosis.

Answer 23

Compression fractures altering the curvature of the spine.

Question 24

What can age-related weakness of back muscles and disability in older population lead to?

Answer 24

Loss of muscle mass, muscle strength, and physical function