the posterior abdominal wall - posterior abdominal muscles

Question 1

what is the posterior abdominal wall formed from?

Answer 1

lumbar vertebrae, pelvic girdle, posterior abdominal muscles, associated fascia

Question 2

what is located on the inner surface of the posterior abdominal wall?

Answer 2

major vessels, nerves, organs

Question 3

what are the posterior abdominal muscles?

Answer 3

quadratus lumborum
psoas major
psoas minor
iliacus
(diaphragm)

Question 4

where is the quadratus lumborum located?

Answer 4

laterally in the posterior abdominal wall

Question 5

what shape is the quadratus lumborum?

Answer 5

thick muscular sheet which is quadrilateral in shape

Question 6

where is quadratus lumborum positioned?

Answer 6

superficially to psoas major

Question 7

what is the origin of the quadratus lumborum?

Answer 7

iliac crest and liolumbar ligament

Question 8

where do the quadratus lumbroum fibres travel?

Answer 8

superomedially

Question 9

where does the quadratus lumborum insert?

Answer 9

onto transverse processes of L1-L4 and inferior border of 12th rib

Question 10

What is the action of quadratus lumborum?

Answer 10

extension and lateral flexion of the vertebral column

also fixes 12th rib during inspiration, so that contraction of diaphragm isn’t wasted

Question 11

what is the innervation of quadratus lumborum?

Answer 11

anterior rami of T12-L4 nerves

Question 12

Where is psoas major located?

Answer 12

near the midline of the posterior abdominal wall, immediately lateral to the lumbar vertebrae

Question 13

where is the origin of psoas major?

Answer 13

transverse processes and vertebral bodies of T12-L5

Question 14

where does the psoas major move from transverse processes and vertebral bodies of T12-L5?

Answer 14

moves inferiorly and laterally, running deep to the inguinal ligament

Question 15

where does psoas major attach?

Answer 15

lesser trochanter of the femur

Question 16

what is the action of psoas major?

Answer 16

flexion of the thigh at the hip and lateral flexion of the vertebral column

Question 17

what is the innervation of psoas major?

Answer 17

anterior rami of L1-L3 nerves

Question 18

where is the psoas minor located?

Answer 18

anterior to psoas major

Question 19

where does the psoas minor originate from?

Answer 19

vertebral bodies of T12-L1

Question 20

where does psoas minor attach to? what is it known as?

Answer 20

ridge on the superior ramus of the pubic bone, known as pectineal line

Question 21

what is the action of psoas minor?

Answer 21

flexion of the vertebral column

Question 22

which nerve innervates psoas minor?

Answer 22

anterior rami of L1 spinal nerve

Question 23

what shape and where is the ilicaus muscle found?

Answer 23

fan-shaped muscle situated inferiorly on the posterior abdominal wall

Question 24

what does the iliacus combine with? what does it form?

Answer 24

iliacus combines with psoas major to form iliopsoas

Question 25

what is the function of iliopsoas?

Answer 25

major flexor of the thigh

Question 26

where does iliacus originate from?

Answer 26

surface of iliac fossa and anterior inferior iliac spine (AIIS)

Question 27

what happens to the fibres of iliacus?

Answer 27

combine with tendon of psoas major

Question 28

where does iliacus insert into?

Answer 28

lesser trochanter of femur

Question 29

what is the action of iliacus?

Answer 29

flexion of the thigh at the hip joint

Question 30

what innervates the iliacus? nerve roots?

Answer 30

femoral nerve (L2-L4)

Question 31

which part of the diaphragm is considered to be part of the posteriro abdominal wall?

Answer 31

posterior aspect of diaphragm

Question 32

what is the psoas sign?

Answer 32

a medical sign that indicates irritation to the iliopsoas group of muscles

Question 33

what is the psoas sign elicited by?

Answer 33

flexion of the thigh at the hip

Question 34

when is the psoas sign test positive?

Answer 34

when the patient reports lower abdominal pain

Question 35

what is an indication of appendicitis?

Answer 35

right sided psoas sign

Question 36

what happens as the iliopsoas contracts? (in appendicitis)

Answer 36

it comes into contact with the inflamed appendix, producing pain