Abd/Pelvic Mm - Actions

Question 1

Nerves of perineum in MALE?
(3 bb of pudendal)

Answer 1

– inf rectal b
– perineal b
– dorsal n of penis b

Question 2

Nerves of perineum in FEMALE?
(3 bb of pudendal)

Answer 2

– inf rectal b
– perineal b
– dorsal n of clitoris b

Question 3

What is the difference between the pudendal nerves in females and males?

Answer 3

dorsal n of clitoris b
dorsal n of penis b

Question 4

rectus abdominis (3)

Answer 4

flexion of lumbar spine
approximate chest to pubis,
increase intrabdominal pressure (to aid in defecation, urination, childbirth, etc)

Question 5

external oblique (3)

Answer 5

bilaterally – aids in trunk flexion
unilaterally – lat bending in lumbar spine, lat rotation of trunk

Question 6

internal oblique (3)

Answer 6

bilaterally – aids in trunk flexion
unilaterally – lat bending, lat rotation

Question 7

transversus abdominis (1)

Answer 7

compression of abdomen

Question 8

quadratus lumborum (3)

Answer 8

lat bending of vertebral column
aids in forced expiration and deep inspiration

Question 9

iliacus (2)

Answer 9

flex and ER thigh (iliopsoas action)

Question 10

psoas major (2)

Answer 10

flex and ER thigh (iliopsoas action)

Question 11

piriformis (1)

Answer 11

ER thigh

Question 12

obturator internus (2)

Answer 12

abduct and ER thigh

Question 13

ischiococcygeus (3)

Answer 13

elevate pelvic floor
support pelvic viscera
flexes coccyx

Question 14

levator ani mm (3)

Answer 14

resist intraabdominal pressure
contraction elevates diaphragm over fecal mass
puborectalis pulls anal canal forward to prevent defecation (major role in fecal continence)

Question 15

superficial transverse perineus

Answer 15

stabilize perineal body (central tendon)

Question 16

bulbospongiosus

***both and male/female action

Answer 16

– both: helps expel last drops of urine, “kegel exercises”

– male: helps propel semen along urethra, may help with penis erection

– female: decreases vaginal orifice, assists in erection of clitoris

Question 17

ischiocavernosus

Answer 17

maintain erection of penis (male) or clitoris (female)

Question 18

deep transverse perineus

Answer 18

both: expel last drops of urine
male: expel last drops of semen

Question 19

external urethral sphincter

Answer 19

both: maintains continence, expels last drops of urine
males: expel last drops of semen

Question 20

external anal sphincter

Answer 20

keeps anal canal and orifice closed

Question 21

• aids in compression of abdominal cavity
• protects and supports abdominal viscera
• aids in stability of trunk/spine & maintain posture

Answer 21

1. rectus abdominis
2. internal/external oblique
3. transverse abdominis