The perineum is the diamond-shaped region below the pelvic diaphragm. It is divided into anterior and posterior triangles by the ischial tuberosities. The anal triangle in the posterior contains the anus and sphincters. The urogenital triangle in the anterior differs in males and females. It contains the superficial and deep perineal spaces, which house various muscles, nerves and vessels. The urogenital diaphragm forms a triangle and separates the spaces, supporting the urethra and vagina. The perineal central tendon provides support and attaches various muscles in the region.

1. PERINEUM & UROGENINTAL
DIAPHRAGM

2. Perineum
• It is a diamond-shaped region below the pelvic diaphragm.
• Boundaries of the perineum are those of the pelvic outlet
• Lower border of symphysis pubis
• Rami of pubis and ischium
• Ischial tuberosity
• Sacrotuberous ligament
• Tip of coccyx
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3. Perineum
Two triangles
• The perineum is divided into
anterior and posterior triangles
by joining the ischial
tuberosities with an imaginary
line
• Urogenital region/ urogenital
triangle (anterior)－differs in
male and female
• Anal region/ anal triangle
(posterior) －similar in
both sexes
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4. Anal triangle
• The anal triangle contains
• the anus
• its sphincters and
• also the ischioanal fossa on either side in both males and females.
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5. Contents of the anal triangle
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6. Urogenital region
Superficial fascia
• The fatty layer
• The membranous layer － superficial
fascia of perineum or Colles’ fascia
• Attached posteriorly to the posterior
border of the urogenital diaphragm
• Laterally to the margins of pubic arch
and ischial tuberosity
• Anteriorly it is continuous with:
• Dartos of the scrotum
• Fascia of the penis
• Scarpa’s fascia
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7. Camper’s fascia
Position of penis
Scarpa’s fascia
Fascia later
Line of fusion
Position of scrotum
superficial fascia of perineum
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8. Urogenital region
Deep fascia
• Superior fascia of urogenital diaphragm
• Inferior fascia of urogenital diaphragm
• Attached
• posteriorly to the posterior border of
the urogenital diaphragm
• Laterally to pubic arch
• In front they fuse together forming the
so-called: transverse perineal
ligament
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9. Urogenital region
• Two spaces
• Deep perineal space
• Superficial perineal
space
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10. Superior fascia of urogenital diaphragm
Inferior fascia of urogenital diaphragm
Superficial fascia of perineum
(Colles’ fascia)
Deep perineal space
Superficial perineal space
Fascia of the penis
Scarpa’s fascia
Dartos of the scrotum
Urogenital region
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11. Urogenital region
Superficial perineal space
• Lies between inferior fascia of urogenital
diaphragm and superficial fascia of
perineum.
• It is closed behind and laterally.
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12. Urogenital region
Superficial perineal space
• Anteriorly, the space communicates
with the potential space lying
between the Scarpa’s fascia and
the anterior abdominal muscles.
• In rupture of cavernous part of
urethra, urine can extravasate from
scrotum upward in front of
symphysis pubis into anterior
abdominal wall deep to Scarpa’s
fascia
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13. Urogenital region
Superficial perineal space
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14. Urogenital region
Superficial perineal space
• Contents
• Posterior part－superficial transverse
muscle of perineum
• Lateral part－crus penis (male), crus of
clitoris (female) and ischiocavernousus
covering them
• Central part－bulb of urethra (male), bulb of
vestibule (female) and bulbocavernousus
covering them
• Branches of pudendal nerves and internal
pudendal vessels
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15. Clitoris
Crus of clitoris
Bulb of vestibule
Great vestibular gland
Superficial transverse
m. of perineal
Ischiocavernousus
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16. Urogenital region
Superficial perineal space
• Contents
• Posterior part－superficial transverse
muscle of perineum
• Lateral part－crus penis (male), crus
of clitoris (female) and
ischiocavernousus covering them
• Central part－bulb of urethra (male),
bulb of vestibule (female) and
bulbocavernousus covering them
• Branches of pudendal nerves and
internal pudendal vessels
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17. Urogenital region
Deep perineal space
• The closed space that is contained
between superior and inferior fascia of
urogenital diaphragm
• Contents
• Deep transverse muscle of perineum
• Bulbourethral gland (male)
• Sphincter of urethra
• Arteries, veins and nerves
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18. Urogenital region
Urogenital diaphragm
• Triangular in shape
• Formed by sphincter of urethra,
deep transverse perineal muscle,
superior and inferior fascia of
urogenital diaphragm
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19. Perineal central tendon
• Wedge-shape fibromuscular mass
• In female, between anal canal and lower end of vagina
• In male, between anal canal and root of penis
• It is larger in the female than in the male and fine support to the posterior
wall of the vagina
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20. Perineal central tendon
• Sphincter ani externus
• Levator ani
• Superficial transverse muscle of
perineum
• Deep transverse muscles of perineum
• Bulbocavernousus
• Sphincter of urethra (male) or
urethrovaginal sphincter (female)
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21. Sphincter ani externus
Levator ani
Superficial transverse muscle of perineum
Bulbocavernousus
Deep transverse muscles of perineum
Sphincter of urethra (male) or
urethrovaginal sphincter (female)
Perineal central tendon
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22. Episiotomy Tear of perineum
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23. THANK YOU FOR YOUR ATTENTION