Urogenital Diaphragm

A. External urethral sphincter

1.action: voluntary control of urination

2.innervation: pudendal nerve



B.Deep transverse perineal muscle

1.fascias

a. superficial fascia (superior fascia)

b. perineal membrane (inferior fascia)

2. action: supports pelvic organs

3.innervation: pudendal nerve

A. Deep perineal space

1.boundaries: between the fascias of the UG diaphragm

2.contents

a.UG diaphragm

b.membranous urethra

B. Superficial perineal space

• 1. boundaries: between perineal membrane and membranous layer of the
• subcutaneous connective tissue (Colles' fascia)

2. embryology of the external genitalia

• a.Indifferent
• stage

i. genital tubercle

ii. labioscrotal swelling

iii. urethral fold

b. differentiation:

• i. dihydrotestosterone
• (+): male

• ii dihydrotestosterone
• (-): female