Quiz 1: Abdominal Muscles

How many abdominal muscles are there?

four

What are the four abdominal muscles?

• Transverse Abdominis

• Internal Oblique

• External Oblique

• Rectus Abdominis

What is the name of this muscle?

transverse abdominis

What is the origin of the transverse abdominis?

the inguinal ligament, iliac crest, thoracolumbar fascia, and cartilage of ribs 6-12

Where does the transverse abdominis insert?

the abdominal aponeurosis to linea alba, xiphoid process, and pubic symphysis

What is the action of the transverse abdominis?

it acts to compress the abdominal contents and stabilize the core

What nerve innervates the transverse abdominis?

thoracoabdominal

What is the name of this muscle?

internal oblique

What is the origin of the internal oblique?

inguinal ligament, iliac crest, and thoracolumbar fascia

Where does the internal oblique insert?

costal cartilage of ribs 8-12, abdominal aponeurosis to linea alba

What are the actions of the internal oblique?

• flex the vertebral column

• laterally flex the vertebral column to the same side

• rotate the vertebral column to the same side

What nerve innervates the internal oblique?

intercostal

What is the name of this muscle?

external oblique

What is the origin of the external oblique?

the external surfaces of ribs 5-12

What is the insertion of the external oblique?

anterior iliac crest and abdominal aponeurosis to linea alba

What are the actions of the external oblique?

• flex the vertebral column

• laterally flex the vertebral column to the same side

• rotate vertebral column to the opposite side

What nerve innervates the external oblique?

intercostal

What is the name of this muscle?

rectus abdominis

What is the origin of the rectus abdominis?

pubic symphysis and pubic crest

Where does the rectus abdominis insert?

the costal cartilage of ribs 5-7 and the xiphoid process

What are the actions of the rectus abdominis?

flex the vertebral column

What nerve innervates the rectus abdominis?

intercostal