ABDOMEN: Muscles of abdominal wall

Question 1

External abdominal oblique - origin

Answer 1

External surfaces of ribs 5-12

Question 2

External abdominal oblique - insertion

Answer 2

Linea alba, Pubic tubercle, Anterior half of iliac crest

Question 3

External abdominal oblique - innervation

Answer 3

Intercostal nerves (T7 T11), Subcostal nerve (T12), Iliohypogastric nerve (L1)

Question 4

External abdominal oblique - function

Answer 4

Bilateral contraction - Trunk flexion, Compresses abdominal viscera, Expiration
Unilateral contraction - Trunk lateral flexion (ipsilateral), Trunk rotation (contralateral)

Question 5

Internal abdominal oblique - origin

Answer 5

Anterior two-thirds of iliac crest, Iliopectineal arch, Thoracolumbar fascia

Question 6

Internal abdominal oblique - insertion

Answer 6

Inferior borders of ribs 10-12, Linea alba, Pubic crest, Pecten pubis (via conjoint tendon)

Question 7

Internal abdominal oblique - innervation

Answer 7

Intercostal nerves (T7-T11), Subcostal nerve (T12), Iliohypogastric nerve (L1), Ilioinguinal nerve (L1)

Question 8

Internal abdominal oblique - function

Answer 8

Bilateral contraction - Trunk flexion, Compresses abdominal viscera, Expiration
Unilateral contraction - Trunk lateral flexion (ipsilateral), Trunk rotation (ipsilateral)

Question 9

Cremaster - origin

Answer 9

Lateral part: Lower edge of internal abdominal oblique and transversus abdominis muscles, Middle of inguinal
ligament
Medial part: Pubic tubercle, Lateral part of pubic crest

Question 10

Cremaster - insertion

Answer 10

Tunica vaginalis of testis

Question 11

Cremaster - innervation

Answer 11

Genital branch of genitofemoral nerve (L1, L2)

Question 12

Cremaster - function

Answer 12

Retraction of testis

Question 13

Transversus abdominis - origin

Answer 13

Internal surfaces of costal cartilages of ribs 7-12, Thoracolumbar fascia, Anterior two thirds of iliac crest, Iliopectineal arch

Question 14

Transversus abdominis - insertion

Answer 14

Linea alba, Aponeurosis of internal abdominal oblique muscle; Pubic crest, Pectinal line of pubis

Question 15

Transversus abdominis - innervation

Answer 15

Intercostal nerves (T7-T11), Subcostal nerve (T12), Iliohypogastric nerve (L1), Ilioinguinal nerve (L1)

Question 16

Transversus abdominis - function

Answer 16

Bilateral contraction - Compresses abdominal viscera, Expiration
Unilateral contraction - Trunk rotation (ipsilateral)

Question 17

Rectus abdominis - origin

Answer 17

Pubic symphysis, Pubic crest

Question 18

Rectus abdominis - insertion

Answer 18

Xiphoid process, Costal cartilages of ribs 5-7

Question 19

Rectus abdominis - innervation

Answer 19

Intercostal nerves (T7-T11), Subcostal nerve (T12)

Question 20

Rectus abdominis - function

Answer 20

Trunk flexion, Compresses abdominal viscera, Expiration

Question 21

Pyramidalis - origin

Answer 21

Pubic crest, Pubic symphysis

Question 22

Pyramidalis - insertion

Answer 22

Linea alba

Question 23

Pyramidalis - innervation

Answer 23

Subcostal nerve (T12)

Question 24

Pyramidalis - function

Answer 24

Tenses linea alba

Question 25

Quadratus lumborum - origin

Answer 25

Iliac crest, Iliolumbar ligament

Question 26

Quadratus lumborum - insertion

Answer 26

Inferior border of rib 12, Transverse processes of vertebrae L1-L4

Question 27

Quadratus lumborum - innervation

Answer 27

Subcostal nerve (T12), Anterior rami of spinal nerves L1-L4

Question 28

Quadratus lumborum - function

Answer 28

Bilateral contraction - Fixes rib 12 during inspiration, Trunk extension Unilateral contraction - Lateral flexion of trunk (ipsilateral)