abdominal wall muscles

Question 1

what are the origin/insertion/action of the external oblique?

Answer 1

origin: external aspect of lower 8 ribs
insertion: aponeurosis to linea alba from xiphoid to symphysis and iliac crest
actions: compress abdomen and laterally rotate and flex spine. depress ribs

Question 2

what are the origin/insertion/action of the internal oblique?

Answer 2

origin: thoracolumbar aponeurosis, iliac crest, and inguinal ligament
insertion: costal cartilages of last 3 or 4 ribs via aponeurosis to linea alba
actions: compress abdomen, laterally rotate/flex spine, depress ribs

Question 3

what are the origin/insertion/action of the transversus abdominis

Answer 3

origin: thoracolumbar fascia, internal aspect of lower 6 costal cartilages, iliac crest
insertion: aponeurosis to linea alba
actions: compress abdomen, depress ribs

Question 4

what are the origin/insertion/action of the rectus abdominis?

Answer 4

origin: crest of pubic bone and pubic symphysis
insertion: the 5, 6, and 7th costal cartilages and xiphoid process
actions: compresses abdomen, flexes spine

Question 5

what is the layer under the transversus abdominis?

Answer 5

transversalis fascia , then parietal peritoneum.

Question 6

whats different below arcuate line

Answer 6

deficiency of rectus sheath

Question 7

what is the blood supply to the abdominal wall? where is it? (whats the origins ?)

Answer 7

superior epigastric *origin from aorta to internal thoracic artery) and inferior epigastric (origin from external iliac artery)
-under rectus abdominis muscle! (which is on the same level as the internal oblique

Question 8

what nerves innervate the abdominal wall? which ventral primary rami do they come from

Answer 8

1. ventral primary rami of L1 origin
   - iliohypogastric nerve and ilioinguinal nerve
2. abdominal branches of ventral primary rami intercostals T7-T8, to T12.

Question 9

what is in the inguinal canal?

Answer 9

spermatic cord in males, round ligament in females, ilioinguinal nerve both, and cremaste muscle extending in both M/F

Question 10

whats the function of the intercostal muscles

Answer 10

expansion and/or contraction of thoracic cavity (external, internal, innermost)

Question 11

what are the arterial origins of the intercostal nerves and arteries?

Answer 11

nv bundle of intercostal artery, vein and nerve

arterial origin: thoracic aorta and internal thoracic artery

innervation origin: ventral primary rami

Question 12

what innervates pectoral muscles and serratus anterior

Answer 12

pect major: median and lateral pectoral nerves
pect minor: median pectoral nerve
serratus anterior: long thoracic nerve

Question 13

what arteries supply pectoral muscles and serratus anterior?

Answer 13

pectoral muscles (major and minor) : thoracoacromial artery and lateral thoracic artery 
serratus anterior: lateral thoracic artery

Question 14

what are the origin/insertion/action of the serratus anterior

Answer 14

origin: ribs 1 to 8 ,9 or 10
insertion: vertebral border of scapula
action: rotate scapula, raise point of shoulder, draw scapula forward

Question 15

what are the origin/insertion/action of the pectoralis minor

Answer 15

origin: ribs 3 to 5
insertion: coracoid process of scapula
action: draws scapula down and forward

Question 16

what are the origin/insertion/action of the pectoralis major

Answer 16

origin: clavicle (medial third) and ribs 2 to 5
insertion: humeral shaft (below greater tubercle of humerus)
action: flexes, adducts and rotates arm medially