Dissection Learning Objectives

Question 1

Iliacus

Answer 1

attachments- from iliac fossa to lesser trochanter of femur

actions- flexion of thigh at the hip joint

innervation- femoral nerve

Question 2

Psoas major

Answer 2

attachments- from transverse processes of T12-L4 to lesser trochanter of femur

actions- flexion of thigh at the hip joint

innervation- ventral rami L1-L3

Question 3

Coccygeus

Answer 3

attachments- from & sacrospinous ligament to coccyx

actions- supports & compresses posterior pelvic floor

innervation- ventral rami S4-5

Question 4

Iliococcygeus

Answer 4

attachments- from ischium & tendinous arch of obturator internus to coccyx & midline raphe

action- support pelvic viscera

innervation- levator ani nerve (S4), inferior rectal nerve (pudendal S3-4), coccygeal plexus

Question 5

Pubococcygeus

Answer 5

attachments- pubis & tendinous arch of obturator internus to coccyx & midline raphe & walls of prostate or vagina

actions- support pelvic viscera & compress vagina

innervation- levator ani nerve (S4), inferior rectal nerve (pudendal S3-4), coccygeal plexus

Question 6

Puborectalis

Answer 6

attachments- pubis & wall of rectum

actions- maintain fecal continence

innervation- levator ani nerve (S4)

Question 7

Internal abdominal oblique

(lower anterior, upper anterior, & lateral fibers)

Answer 7

attachments- from thoracolumbar fascia to inguinal ligament, iliac crest & rectus sheath

actions- flexion & rotation of the trunk, & compression of the abdominal cavity

innervation- lower thoracic & L1 ventral rami T7-12, L1, iliohypogastric and ilioinguinal, ventral rami

Question 8

External abdominal oblique

(anterior & lateral fibers)

Answer 8

attachments- from lower 8 ribs to iliac crest & rectus sheath, TL fascia attachment as well?

actions- flexion & rotation of the trunk, & compression of the abdominal cavity

innervation- ventral rami T7-12

Question 9

Quadratus lumborum

Answer 9

attachments- from 12th rib & transverse processes of L1-4 to iliolumbar ligament & iliac crest

actions- extension & lateral flexion of the trunk, and fixes 12th rib during respiration

innervation- Lumbar plexus ventral rami T12-L3

Question 10

Rectus abdominis

Answer 10

attachments- from xiphoid process & adjacent costal cartilages of ribs 5-7 to pubic crest & tubercle (symphysis)

actions- flexion of trunk & compression of abdominal cavity

innervation- lower thoracic ventral rami T5-12

Question 11

Transversus abdominis

Answer 11

attachments- from lower six costal cartilages & thoracolumbar fascia to inguinal ligament, iliac crest & rectus sheath

actions- compression of the abdominal cavity

innervation- lower thoracic T7-12, ventral divisions