Muscles of the abdominal wall

Question 1

How many flat muscles are there?

Answer 1

3

Question 2

How many vertical muscles are there?

Answer 2

2

Question 3

What is an aponeurosis?

Answer 3

a broad flat tendon

covers the vertical rectus abdominis muscle

Question 4

What do all the aponeuroses of the flat muscles form when entwined in the midline?

Answer 4

linea alba

Question 5

Where does the linea alba extend from/to?

Answer 5

a fibrous structure that extends from the xiphoid process of the sternum to the pubis symphysis

Question 6

origin of the external oblique

Answer 6

ribs 5-12

Question 7

insertion of the external oblique (2)

Answer 7

iliac crest and pubic tubercle

Question 8

innervation of the external oblique

Answer 8

thoracoabdominal nerves (T7-T11) and subcostal nerve (T12)

Question 9

function of the external oblique

Answer 9

contralateral rotation of the torso

Question 10

origin of the internal oblique (3)

Answer 10

inguinal ligament, iliac crest and lumbodorsal fascia

Question 11

insertion of internal oblique

Answer 11

ribs 10-12

Question 12

innervation of internal oblique

Answer 12

thoracoabdominal nerves (T7-T11), subcostal nerve (T12) and branches of the lumbar plexus

Question 13

functions of internal oblique

Answer 13

bilateral contraction compresses of the abdomen, while unilateral contraction ipsilaterally rotates the torso

Question 14

origin of the transverses abdominis (4)

Answer 14

inguinal ligament, costal cartilages 7-12, iliac crest and thoracolumbar fascia

Question 15

insertion of the transverses abdominis (4)

Answer 15

conjoint tendon, xiphoid process, linea alba and pubic crest

Question 16

innervation of transverses abdominis

Answer 16

thoracoabdominal nerves (T7-T11), subcostal nerve (T12) and branches of the lumbar plexus

Question 17

function of transverses abdominis

Answer 17

compression of abdominal contents

Question 18

origin of rectus abdominis (1)

Answer 18

pubis crest

Question 19

insertion of rectus abdominis (2)

Answer 19

xiphoid process of the sternum and costal cartilages of ribs 5-7

Question 20

innervation of the rectus abdominis

Answer 20

thoracoabdominal nerves (T7-T11)

Question 21

functions of the rectus abdominis

Answer 21

assists the flat muscles in compressing the abdominal viscera, the rectus abdominis also stabilises the pelvis during walking and depresses the ribs

Question 22

origin of the pyramidalis (2)

Answer 22

pubic crest and pubis symphysis

Question 23

insertion of the pyramidalis

Answer 23

linea alba

Question 24

innervation of the pyramidalis

Answer 24

subcostal nerve (T12)

Question 25

function of the pyramidalis

Answer 25

acts to tense the linea alba

Question 26

what is the rectus sheath formed by?

Answer 26

aponeuroses of the three flat muscles and encloses the rectus abdominis and pyramidalis muscles