GA Lab 1 - Osteology and Gluteal Region

Question 1

What is the anterior wall of the pelvis made of?

Answer 1

1. Bodies of pubic bones
2. Pubic rami
3. Pubic symphysis

Question 2

What is the posterior wall of the pelvis made of?

Answer 2

1. Sacrum
2. Coccyx
3. Piriformis muscles

Question 3

Piriformis:

1. Origin
2. Insertion
3. Innervation
4. Function

Answer 3

1. Anterior surface of sacrum between anterior sacral foramina
2. Medial side of superior border of greater trochanter of femur
3. Branches from S1 and S2
4. Lateral rotation of extended hip joint and abduction of flexed hip (same as obturator internus)

Question 4

What are the lateral walls of the pelvis made of?

Answer 4

1. Hip bones
2. Obturator membrane
3. Sacrotuberous ligaments
4. Sacrospinous ligaments
5. Obturator internus muscle

Question 5

Obturator internus:

1. Origin
2. Insertion
3. Innervation
4. Function

Answer 5

1. Anterolateral wall of true pelvis (deep surface of obturator membrane and surrounding bone)
2. Medial surface of greater trochanter of femur
3. Nerve to obturator internus: L5, S1
4. Lateral rotation of extended hip joint and abduction of flexed hip (same as piriformis)

Question 6

Location of obturator internus?

Answer 6

Obturator foramen

Question 7

What closes most of the obturator foramen?

Answer 7

Obturator membrane

Question 8

Where is the obturator canal located? What does it contain? Purpose?

Answer 8

Superiorly to obturator foramen between the membrane and adjacent bone, providing a route of communication between the lower limb and the pelvic cavity and containing obturator nerve and vessels

Question 9

What passes through the greater sciatic foramen? What does it mean for relative location?

Answer 9

Located superior to the piriformis: superior gluteal nerves and vessels

Located inferior to the piriformis:

1. Inferior gluteal nerves and vessels
2. Sciatic nerve
3. Pudendal nerve
4. Internal pudendal vessels
5. Posterior femoral cutaneous nerves
6. Nerves to the obturator internus and quadratus femoris muscles

Question 10

What passes through the lesser sciatic foramen?

Answer 10

1. Tendon of the obturator internus muscles
2. Pudendal nerve
3. Internal pudendal vessels

Question 11

What are ischio-anal fossae?

Answer 11

Inverted wedge-shaped gutters in the anal triangle on each side of the anal aperture between the levator ani muscles and adjacent pelvic walls (obturator internus muscles) as the two structures diverge inferiorly

Question 12

Lateral wall of ischio-anal fossae?

Answer 12

Obturator internus muscle

Question 13

Medial wall of ischio-anal fossae?

Answer 13

Levator ani muscles

Question 14

Superficial wall/base of ischio-anal fossae?

Answer 14

Skin

Question 15

What is the iliac crest?

Answer 15

Entire superior margin of the ilium that is thickened that terminates anteriorly as the anterior superior iliac spine and posteriorly as the posterior superior iliac spine

Question 16

What is the tubercle of the iliac crest?

Answer 16

A prominent tubercle of the iliac crest projecting laterally near the anterior end of the crest

Question 17

What is the iliac tuberosity?

Answer 17

Posterior end of the crest that thickens

Question 18

What are anterior and posterior sacral foramina? What passes through?

Answer 18

4 pairs of anterior sacral foramina on the anterior surface of the sacrum for anterior rami of S1 to S4

4 pairs of posterior sacral foramina on the posterior surface for the posterior rami of S1 to S4

In between sacral alae

Question 19

What is the arcuate line? What to note?

Answer 19

Ridge separating the upper and lower parts of the ilium that is rounded

Makes up part of the pelvic inlet

Question 20

What is the iliopubic eminence?

Answer 20

Rounded elevation on the superior surface of the pelvic bone at the junction of the ilium and the superior ramus of the pubis

Question 21

What is the pecten pubis? Other name? What to note?

Answer 21

Sharp superior margin of the triangular surface of the superior pubic ramus, which forms part of the linea terminalis of the pelvic bone

= pectineal line

Makes up part of the pelvic inlet

Question 22

Where are the iliolumbar and lumbosacral ligaments?

Answer 22

Extend from the expanded transverse processes of vertebra L5 to the ilium and the sacrum, respectively

Question 23

Where is the anterior longitudinal ligament?

Answer 23

Across the anterior surface of the vertebral column

Question 24

Where is the posterior longitudinal ligament?

Answer 24

Across the posterior surface of the vertebral column

Question 25

What is the anterior sacroiliac ligament?

Answer 25

Thickening of the fibrous membrane of the joint capsule that runs anteriorly and inferiorly to the joint

Question 26

What is the posterior sacroiliac ligament?

Answer 26

Covers the interosseous sacro-iliac ligament

Question 27

What is the supraspinous ligament?

Answer 27

Ligament across all spinous processes of all vertebrae of the vertebral column

Question 28

Boundaries of urogenital triangle?

Answer 28

Inferior pubic arch superiorly and 2 pubic rami laterally

Question 29

Boundaries of anal triangle?

Answer 29

Coccyx posteriorly and 2 ischial tuberosities laterally

Question 30

What is the epimysum?

Answer 30

Deep fascia of gluteus maximus muscle

Question 31

Muscle attached to the sacrotuberous ligament?

Answer 31

Gluteus maximus muscle