thoracic and abdominal wall muscles

Question 1

internal intercostal

Answer 1

O and I: lower margin of rib to upper margin of next lower rib (forward and upward from costal angle to sternum) 
N: 1st to 11th intercostal nerves
A: lowers ribs (expiration)
supports intercostal spaces
stabilizes chest wall

Question 2

innermost intercostal

Answer 2

O and I: lower margin of rib to upper margin of next lower rib (forward and upward from costal angle to sternum) 
N: 1st to 11th intercostal nerves
A: lowers ribs (expiration)
supports intercostal spaces
stabilizes chest wall

Question 3

transversus thoracis

Answer 3

O: sternum and xiphoid process (inner surface)
I: 2nd to 6th ribs (costal cartilage, inner surface)
N: 2nd to 6th intercostal nerves
A: Weakly lowers ribs (expiration)

Question 4

external oblique

Answer 4

O: 5th to 12th ribs (outer surface)
I: linea alba;
pubis tubercle;
anterior iliac crest
N: intercostal nerves T7-T12
A: Unilateral: bends trunk to same side; rotates trunk to opposite side
Bilateral: flexes trunk, compresses abdomen, stabilizes pelvis

Question 5

internal oblique

Answer 5

O: thoracolumbar fascia (deep layer);
iliac crest (intermediate line);
anterior superior iliac spine;
iliopsoas fascia
I: 10th to 12th ribs (lower borders);
linea alba (anterior and posterior layers)
N: intercostal nerves T7-T12;
iliohypogastric nerve;
ilioinguinal nerve
A: Unilateral: bends trunk to same side; rotates trunk to opposite side
Bilateral: flexes trunk, compresses abdomen, stabilizes pelvis

Question 6

transverses abdominus

Answer 6

O: 7th to 12th costal cartilages (inner surfaces);
thoracolumbar fascia (deep layer);
iliac crest;
anterior superior iliac spine (inner lip);
iliopsoas fascia 
I: linea alba; 
pubic crest 
N: intercostal nerves T7-T12;
iliohypogastric nerves;
ilioinguinal nerves 
A: unilaterally- rotates trunk to same side 
bilaterally- compresses abdomen

Question 7

rectus abdominus- lateral head

Answer 7

O: crest of pubis to pubic tubercle 
I: cartilages of 5th to 7th ribs,
xiphoid process of sternum
N: intercostal nerves T5- T12
A: flexes trunk;
compresses abdomen;
stabilizes pelvis

Question 8

rectus abdominis- medial head

Answer 8

O: anterior region of pubic symphysis 
I: cartilages of 5th to 7th ribs,
xiphoid process of sternum
N: intercostal nerves T5- T12
A: flexes trunk;
compresses abdomen;
stabilizes pelvis

Question 9

diaphragm- costal part

Answer 9

O: 7th to 12th ribs (inner surface; lower margin of costal arch)
I: Central tendon
N: phrenic nerve C4-C5 (cervical plexus)
A: principal muscle of respiration (diaphragmatic and thoracic breathing);
aids in compressing abdominal viscera (abdominal press)

Question 10

diaphragm-lumbar part

Answer 10

O: ~medial part: L1-L3 vertebral bodies, intervertebral disks, and anterior longitudinal ligament as right and left crura
~lateral part: lateral and medial arcuate ligaments
I: central tendon
N: phrenic nerves C3-C5 (cervical plexus)
A: principal muscle of respiration (diaphragmatic and thoracic breathing);
aids in compressing abdominal viscera (abdominal press)

Question 11

diaphragm- sternal part

Answer 11

O: xiphoid process (posterior surface)
I: central tendon
N: phrenic nerve C3-C5 (cervical plexus)
A: principal muscle of respiration (diaphragmatic and thoracic breathing);
aids in compressing abdominal viscera (abdominal press)

Question 12

external intercostal

Answer 12

O and I: lower margin of rib to upper margin of next lower rib (costal tubercle from upper to chondro-osseous junction of lower)
N: 1st to 11th intercostal nerves
A: raises ribs (inspiration)
supports intercostal spaces 
stabilizes chest wall