Abdominal Muscles

Question 1

External Oblique origin and insertion

Answer 1

Origin- External surfaces of ribs 5-12

Insertion- Anterior part of iliac crest, abdominal aponeurosis to linea alba

Question 2

External Oblique Action

Answer 2

Unilaterally: Laterally flex vertebral column to the same side; Rotate vertebral column to the opposite side

Bilaterally: Flex the vertebral column
Compress Abdominal contents

Question 3

Internal oblique origin and insertion

Answer 3

Origin- Lateral inguinal ligament, iliac crest and thoracolumbar fascia

Insertion- Internal surface of lower three ribs, abdominal aponeurosis to linea alba

Question 4

Internal oblique Action

Answer 4

Unilaterally: Laterally flex vertebral column to the same side; Rotate vertebral column to the same side

Bilaterally: Flex the vertebral column
Compress abdominal contents

Question 5

Transverse Abdominis origin and insertion

Answer 5

Origin- Lateral inguinal ligament, iliac crest, thoracolumbar fascia and internal surface of lower six ribs

Insertion- Abdominal aponeurosis to linea alba

Question 6

Transverse Abdominis Action

Answer 6

Compress the abdominal contents

Question 7

Rectus Abdominis origin and insertion

Answer 7

Origin- Pubic crest, pubic symphysis

Insertion- Cartilage of fifth, sixth and seventh ribs and xiphoid process

Question 8

Rectus Abdominis Action

Answer 8

Flex the vertebral column

Tilt the pelvis posteriorly

Question 9

Quadratus Lumborum origin and insertion

Answer 9

Origin-Posterior Iliac Crest

Insertion- Last rib and transverse processes of first through fourth lumbar vertebrae

Question 10

Quadratus Lumborum Action

Answer 10

Unilaterally: Laterally tilt the pelvis; Laterally flex the vertebral column to the same side; Assist to extend the vertebral column
Bilaterally: Fix the last rib during forced inhalation and exhalation

Question 11

Psoas Major origin and insertion

Answer 11

Origin- Bodies and transverse processes of lumbar vertebrae

Insertion- Lesser Trochanter

Question 12

Psoas Major Action

Answer 12

With origin fixed: Flex the hip; May laterally rotate the hip

with insertion fixed: Flex the trunk toward the thigh; Tilt the pelvis anteriorly

Unilaterally: Assist to laterally flex the the lumbar spine

Question 13

Iliacus origin and insertion

Answer 13

Origin- Iliac fossa

Insertion- Lesser trochanter

Question 14

Iliacus Action

Answer 14

With origin fixed: Flex the hip; May laterally rotate the hip

With insertion fixed: Flex the trunk toward the thigh; Tilt pelvis anteriorly