Extra: anatomy of the pelvic wall and floor

Question 1

What is the inferior pelvic aperture formed by?

Answer 1

It runs from the inferior part of the pubic symphysis → ischiopubic ramus → sacrotuberous ligament → tip of coccyx.

Question 2

What type of joint is the pubic symphysis?

Answer 2

secondary cartilaginous joint (symphysis) with hyaline cartilage on the symphyseal surface and
united by fibrocartilage

Question 3

What type of joint is the sacroiliac joint?

Answer 3

synovial plane joints with a posterior fibrous component.

Question 4

What is the orientation of the bony pelvis?

Answer 4

The ASIS and pubic tubercles are in coronal plane, the superior symphysis pubis and coccyx are in horizontal plane.
Planes of pelvic inlet, about 60o, outlet about 10o above horizontal

Question 5

Origin and insertion of the coccygeus muscle

Answer 5

Runs from the ischial spine to coccyx. Located on the internal surface of sacrospinous ligament.

Question 6

Function, origin and insertion of the levator ani muscle.

Answer 6

Major part of the pelvic diaphragm, supports pelvic viscera and contributes to sphincter mechanism of the anal canal. Attaches to the body of pubis, ischial spine and tendinous arch (which runs across the inner surface of the obturator internus muscle) to the perineal body, coccyx, and anococcygeal lig.

Question 7

Name the parts of the pubococcygeus m

Answer 7

Male – Puboprostaticus, puboperinealis, pubo-analis,

Female – Pubovaginalis, puboperinealis, pubo-analis.

Question 8

What is the perineum?

Answer 8

Diamond shaped region between thighs and buttocks, subdivided into anal and urogenital triangles. The anal triangle contains the anus and anal canal. The urogenital triangle contains the urethra, external genitalia and inferior vagina.

Question 9

What are the boundaries of the perineum?

Answer 9

Most inferior part of the trunk – located below pelvic diaphragm. Boundaries: pubic symphysis and body of pubis, ischiopubic ramus, ischial tuberosity, sacrotuberous ligament, coccyx, obturator internus.

Question 10

What is the pudendal canal?

Answer 10

The Pudendal canal is located on the lateral wall of ischioanal fossa, on the obturator internus muscle. Contains internal pudendal vessels, pudendal nerve