PELVIS & PERINEUM: Pelvic floor muscles

Question 1

PELVIC DIAPHRAGM

Levator ani: Puborectalis - origin

Answer 1

Posterior surface of bodies of pubic bones

Question 2

PELVIC DIAPHRAGM

Levator ani: Pubococcygeus - origin

Answer 2

Posterior surface of bodies of pubic bones (lateral to puborectalis)

Question 3

PELVIC DIAPHRAGM

Levator ani: Iliococcygeus - origin

Answer 3

Tendinous arch of interal obturator fascia, Ischial spine

Question 4

PELVIC DIAPHRAGM

Levator ani: Puborectalis - insertion

Answer 4

None (forms ‘puborectal sling’ posterior to rectum)

Question 5

PELVIC DIAPHRAGM

Levator ani: Pubococcygeus - insertion

Answer 5

Anococcygeal ligament, Coccyx, Perineal body and musculature of prostate/vagina

Question 6

PELVIC DIAPHRAGM

Levator ani: Iliococcygeus - insertion

Answer 6

Anococcygeal ligament, Coccyx

Question 7

PELVIC DIAPHRAGM

Levator ani: Puborectalis / Pubococcygeus / Iliococcygeus - innervation

Answer 7

Nerve to levator ani (S4) (Pubococcygeus also receives branches via inferior rectal/perineal branches of pudendal nerve (S2-S4))

Question 8

PELVIC DIAPHRAGM

Levator ani: Puborectalis / Pubococcygeus / Iliococcygeus - function

Answer 8

Supports pelvic viscera, Increases intraabdominal pressure, Assists with fecal and urinary continence

Question 9

PELVIC DIAPHRAGM

Coccygeus - origin

Answer 9

Ischial spine

Question 10

PELVIC DIAPHRAGM

Coccygeus - insertion

Answer 10

Inferior end of sacrum, Coccyx

Question 11

PELVIC DIAPHRAGM

Coccygeus - innervation

Answer 11

Anterior rami of spinal nerves S4 & S5

Question 12

PELVIC DIAPHRAGM

Coccygeus - function

Answer 12

Supports pelvic viscera, Flexes coccyx

Question 13

PELVIC DIAPHRAGM

Obturator internus - origin

Answer 13

Ischiopubic ramus, Posterior surface of obturator membrane

Question 14

PELVIC DIAPHRAGM

Obturator internus - insertion

Answer 14

Greater trochanter of femur

Question 15

PELVIC DIAPHRAGM

Obturator internus - innervation

Answer 15

Nerve to obturator internus (L5-S2)

Question 16

PELVIC DIAPHRAGM

Obturator internus - function

Answer 16

Hip joint: Thigh external rotation, Thigh abduction (from flexed hip); Stabilises head of femur in acetabulum

Question 17

PELVIC DIAPHRAGM

Piriformis - origin

Answer 17

Anterior surface of S2-S4 segments of sacrum, Superior margin of greater sciatic notch, Sacrotuberous ligament

Question 18

PELVIC DIAPHRAGM

Piriformis - insertion

Answer 18

Greater trochanter of femur

Question 19

PELVIC DIAPHRAGM

Piriformis - innervation

Answer 19

Nerve to piriformis (S1, S2)

Question 20

PELVIC DIAPHRAGM

Piriformis - function

Answer 20

Hip joint: Thigh external rotation, Thigh abduction (from flexed hip); Stabilises head of femur in acetabulum

Question 21

PERINEAL MUSCLES

External anal sphincter - origin

Answer 21

Skin/fascia surrounding anal canal/anus

Question 22

PERINEAL MUSCLES

External anal sphincter - insertion

Answer 22

Perineal body, Anococcygeal ligament (encircles anus)

Question 23

PERINEAL MUSCLES

External anal sphincter - innervation

Answer 23

Inferior anal/rectal branch of pudendal nerve (S2-S4)

Question 24

PERINEAL MUSCLES

External anal sphincter - function

Answer 24

Constricts anal canal, Supports pelvic floor

Question 25

PERINEAL MUSCLES Bulbospongiosus [male] - origin

Answer 25

Perineal body, Median penile raphe

Question 26

PERINEAL MUSCLES Bulbospongiosus [female] - origin

Answer 26

Perineal body

Question 27

PERINEAL MUSCLES Bulbospongiosus [male] - insertion

Answer 27

Perineal membrane, Dorsal aspect of corpus spongiosum and corpora cavernosa, Fascia of bulb of penis

Question 28

PERINEAL MUSCLES Bulbospongiosus [female] - insertion

Answer 28

Pubic arch, Fascia of corpora cavernosa and clitoris

Question 29

PERINEAL MUSCLES Bulbospongiosus - innervation

Answer 29

Deep branch of perineal nerve (of pudendal nerve) (S2-S4)

Question 30

PERINEAL MUSCLES Bulbospongiosus [male] - function

Answer 30

Compresses bulb of penis during urination/ejaculation, Assists in erection of penis, Supports perineal body

Question 31

PERINEAL MUSCLES Bulbospongiosus [female] - function

Answer 31

Assists in erection of clitoris/bulb of vestibule, Supports perineal body

Question 32

PERINEAL MUSCLES Ischiocavernosus - origin

Answer 32

Ischial tuberosity & ramus

Question 33

PERINEAL MUSCLES Ischiocavernosus - insertion

Answer 33

Crus of clitrois or penis

Question 34

PERINEAL MUSCLES Ischiocavernosus - innervation

Answer 34

Deep branch of perineal nerve (of pudendal nerve) (S2-S4)

Question 35

PERINEAL MUSCLES Ischiocavernosus - function

Answer 35

Pushes blood from root of clitoris/penis to body i.e. maintains erection of penis/clitoris

Question 36

PERINEAL MUSCLES Deep transverse perineal muscle - origin

Answer 36

Inferior pubic rami, Ischial rami

Question 37

PERINEAL MUSCLES Deep transverse perineal muscle - insertion

Answer 37

Walls of vagina (female)/Prostate (male), Perineal body

Question 38

PERINEAL MUSCLES Deep transverse perineal muscle - innervation

Answer 38

Deep branch of perineal nerve (of pudendal nerve) (S2-S4)

Question 39

PERINEAL MUSCLES Deep transverse perineal muscle - function

Answer 39

Strengthens pelvic floor/perineal body to support abdominopelvic viscera

Question 40

PERINEAL MUSCLES Superficial transverse perineal muscle - origin

Answer 40

Ischial tuberosities

Question 41

PERINEAL MUSCLES Superficial transverse perineal muscle - insertion

Answer 41

Perineal body

Question 42

PERINEAL MUSCLES Superficial transverse perineal muscle - innervation

Answer 42

Deep branch of perineal nerve (of pudendal nerve) (S2-S4)

Question 43

PERINEAL MUSCLES Superficial transverse perineal muscle - function

Answer 43

Strengthens pelvic floor/perineal body to support abdominopelvic viscera

Question 44

PERINEAL MUSCLES External urethral sphincter [male] - origin & insertion

Answer 44

Encircles membranous urethra, extends to anterior aspect of prostatic urethra/neck of urinary bladder and to ischial rami (compressor urethrae)

Question 45

PERINEAL MUSCLES External urethral sphincter [female] - origin & insertion

Answer 45

Encircles urethra/neck of bladder, extends to ischial rami (compressor urethrae), encircles urethra/vagina (urethrovaginal sphincter)

Question 46

PERINEAL MUSCLES External urethral sphincter - innervation

Answer 46

Deep branch of perineal nerve (of pudendal nerve) (S2-S4)

Question 47

PERINEAL MUSCLES External urethral sphincter - function

Answer 47

Maintains urinary continence (compresses urethra) (Female: Constricts vaginal canal)