Abdominal Cavity IV

Question 1

What are the hiatal openings of the diaphragm?

Answer 1

Inferior Vena Cava - T8

Esophagus - T10

Aorta - T12

Question 2

What are the motor and sensory innervations of the diaphragm?

Answer 2

Motor: Phrenic C3,4,5

Sensory: Phrenic (C3,4,5), intercostal (T5-11), and subcostal (T12)

Question 3

What are the arcuate ligaments of the diaphragm and what structures do they occur at?

Answer 3

Lateral arcuate ligament - diaphragm meets quadratus lumborum

Median arcuate ligament - diaphragm arches over aorta and R. and L. crus meet

Medial arcuate ligament - diaphragm meets psoas major

Question 4

What are the origins and insertions of the psoas major?

Answer 4

Origin: Transverse processes of lumbar vertebrae and sides of vertebral bodies T12-S1

Insertion: Lesser trochanter

Question 5

What is the action and innervation of the psoas major?

Answer 5

Flexes thigh, flexes vertebral column laterally and when sitting, acts inferiorly to flex trunk

Innerv: Lumbar plexus via ant. branches of nerves L1-3

Question 6

What are the origins and insertions of the psoas minor?

Answer 6

Origin: Sides of vertebral bodies of T12-L1

Insertion: Pectineal line and iliopubic eminence

Question 7

What is the action and innervation of the psoas minor?

Answer 7

Trunk flexion

Innervation: L1

Question 8

What is the origin and insertion of the illiacus?

Answer 8

Origin: Superior 2/3rd of illiac fossa, sacrum and ant. sacro-iliac ligaments

Insertion: Lesser trochanter and shaft inferior to it

Question 9

What is the action and innervation of the illiacus?

Answer 9

Flexes thigh and stabilizes hip joint

Innerv: Femoral nerve (L2-L4)

Question 10

What is the origin and insertion of the quadratus lumborum?

Answer 10

Origin: Medial half of inferior border of 12th rib and tips of lumbar transverse processes

Insertion: Iliolumbar ligament and internal lip of iliac crest

Question 11

What is the action and innervation of the quadratus lumborum?

Answer 11

Extend and laterally flexes vertebral column, fixes 12th rib during inspiration

Innerv: Ant. branches of T12 and L1-4 nerves

Question 12

What is the spinal level of the subcostal nerve and what does it innervate?

Answer 12

T12

Ext. oblique
Skin of anterolateral abdominal wall

Question 13

What is the spinal level of the illiohypogastric nerve and what does it innervate?

Answer 13

L1

Abdominal muscles
Overlying skin

Question 14

What is the spinal level of the illioinguinal nerve and what does it innervate?

Answer 14

L1

Skin of inguinal and pubic regions

Question 15

What is the spinal level of genitofemoral nerve and what does it innervate?

Answer 15

L1-2

Skin below the inguinal ligament including cremaster muscle

Question 16

What is the spinal level of the lateral femoral cutaneous nerve and what does it innervate?

Answer 16

L2-L3

Anterolateral skin of thigh

Question 17

What is the spinal level of the femoral nerve and what does it innervate?

Answer 17

L2-L4

Illiacus, hip flexors, knee extensors
Skin of anterior leg

Question 18

What is the spinal level of the obturator nerve and what does it innervate?

Answer 18

L2-L4

Thigh adductors
Skin of medial thigh

Question 19

What is the spinal level of the lumbosacral trunk and what does it innervate?

Answer 19

L4-L5

Continues to becomes part of sciatic nerve