Innervations and actions of thorax muscles

Question 1

external intercostals action

Answer 1

elevate ribs during inspiration

Question 2

internal intercostals action

Answer 2

draw ribs downward during forced expiration

Question 3

tranversus thoracis action

Answer 3

depresses the ribs

Question 4

quadratus lumborum action

Answer 4

• extension and side flexion of lumbar spine
• expiration

Question 5

psoas major action

Answer 5

• forward flexion and side flexion of lumbar spine
• flexion of the hip joint

Question 6

iliacus action

Answer 6

flexion of hip joint

Question 7

rectus abdominis action

Answer 7

• expiration
• flexion of the spine

Question 8

external oblique action bilaterally

Answer 8

flexion of the trunk and posterior tilt of the pelvis

Question 9

external oblique action unilaterally

Answer 9

• lateral flexion
• contralateral rotation of the trunk

Question 10

internal oblique action bilaterally

Answer 10

• flexion of the trunk
• posterior tilt of the pelvis

Question 11

internal oblique action unilaterally

Answer 11

• lateral flexion
• ipsilateral rotation of the trunk

Question 12

tranversus abdominis action bilaterally

Answer 12

• stabilization of attachment sites for other abdominal muscles
• compression of the abdominal cavity

Question 13

transversus abdominis innervation

Answer 13

• lower six thoracic nerves
• first lumbar nerve

Question 14

internal oblique innervation

Answer 14

• lower six thoracic nerves
• first lumbar nerve

Question 15

external oblique innervation

Answer 15

lower six thoracic nerves

Question 16

rectus abdominis innervation

Answer 16

Lower six or seven thoracic nerves

Question 17

iliacus innervation

Answer 17

femoral nerve

Question 18

psoas major innervation

Answer 18

branches of ventral rami L1-L3

Question 19

quadratus lumborum innervation

Answer 19

ventral ramus of spine nerve roots T12-L3

Question 20

Transversus thoracis innervation

Answer 20

intercostal nerves

Question 21

internal intercostals innervation

Answer 21

intercostal nerves

Question 22

external intercostals innervation

Answer 22

intercostal nerves