Abdominal Muscles

Question 0

External abdominal oblique

Answer 0

PA: lower 8 ribs on exterior and inferior surfaces

DA: anterior half iliac crest, ASIS, abdominal aponeurosis to linea alba

I: ventral rami t7-12

A: trunk flexion, compresses abdominal viscera and posteriorly tilts pelvis, unilateral SB, and contra rotation

Question 1

Rectus Abdominus

Answer 1

PA: pubic crest, symphysis, and ligaments

DA: xiphoid process, costal cartilage of ribs 5-7

I: ventral rami of t6-12

A: bilat flex trunk and compresses abdominal viscera, posterior pelvic tilt

Question 2

Internal abdominal oblique

Answer 2

PA: lateral 2/3 ingiunal ligament, anterior iliac crest, thoracolumbar fascia

DA: lower 3-4 ribs and their costal cartilage, aponeurosis to midline linea alba and public crest

I: ventral rami t7-12

A: bilat trunk flexion, compresses viscera, ipsi SB and rotation; CC: posteriorly tilts pelvis

Question 3

Transversus abdominus

Answer 3

PA: lateral 1/3 inguinal ligament, anterior iliac crest, thoracolumbar fascia between 12th rib and iliac crest, lower 6 costal cartilages

DA: aponeurosis of linea alba to pubic crest

I: ventral rami of t7-12

A: compression of viscera, lumber stabilization

Question 4

Quadratis Lumborum

Answer 4

PA: posteromedial iliac crest, iliolumbar ligament

DA: 12th rib along medial 1/2 of lower border, TPs of t12-l4

I: ventral Rami of t12-l3

A: stabilizes 12th rib and lumbar spine, ipsi SB, bilat extension, hikes hip