Surgical anatomy of female pelvis, SUI, Uro-gynaecology, Urology

1. Surgical Anatomy
Of The Female Pelvis.
Dr Sonu Kumar Plash

2. Bony pelvis
• Divided into two continuous compartments (true and false pelvis).
• True pelvis- 4 bones.
• 2 hip bones, Sacrum, Coccyx.
• Each hip bone made up of-ilium, ischium and the pubis.
• During vaginal prolapse surgery, the ischial spine is an important landmark for
identifying a safe location for fixation of apical suspension sutures.
• The pubic rami, ischial spines, and sacrum are the main anchoring points for the
ligamentous attachments supporting the pelvis.

4. Division of true and false pelvis.
• The pelvis is divided into the true and false
pelvis by an oblique line passing from the
sacral promontory posterior to the superior
margin of the pubic symphysis,
corresponding with the iliopectineal line.
• The pelvic brim defines the pelvic inlet.
• The true pelvis -below the pelvic brim.
• False pelvis is above the brim.

5. • In standing position the anterior
superior iliac spine and pubic
symphysis lie parallel to each other.
• The pelvic inlet faces anteriorly,
allowing pressure of the intra-
abdominal and intrapelvic
contents to be directed to the
bony pelvis rather than the
muscles and the fascia.

6. The principal differences in the female
true and false pelvises.
• The female pelvis is larger and broader with sides wider apart.
• The female inlet is oval (as compared with the heart-shaped
male inlet) and wider, which contributes to the weakness of the
pelvic floor.
• The angle between the inferior pubic rami is obtuse in women.
• The female sacrum is shorter and wider with a less pronounced
sacral promontory.

7. Fascia and Peritoneum
• Divided into three strata: Inner, Intermediate, and Outer.
1. Inner strata- Rectal fascia, covers the anterior and lateral rectal wall, vessels,
and nerves forming part of denonvilliers fascia.
2. Intermediate strata- surround the uterus and supporting vessels.
• Most of the support of the pelvic organs comes from the retroperitoneal
connective tissue, which is derived from the intermediate stratum.
• This includes Pubovesical and Pubocervical fascia that surround the vagina.
• Fascia attached to the uterus is called the Parametrium, and the fascia
surrounding the vagina is called the Paracolpium.

9. 3- Outer stratum-
• Transversalis fascia is part of the outer stratum and is
continuous with the endopelvic and lateral pelvic fascia, which
both play a key role at the exit points of the pelvic organs.
• Endopelvic fascia The urogenital organs are connected
bilaterally to the pelvic walls by neurovascular mesenteric
condensations en-sheathed by a meshwork of loose connective
and adipose tissue and lying above the perineal membrane. This
connections is known as the endopelvic fascia.
• Iliac fascia- covers the iliacus and psoas muscles. This attaches
to the iliac crest and runs down to the tendinous arch (white
line) and is continuous with the posterior part of the inguinal
ligament, pectineal fascia, and obturator fascia.
• Obturator fascia- covers obturator internus and piriformis
muscles.

10. Transversalis fascia

11. Iliac fascia

12. Obturator fascia

13. • Arcus tendineus fascia pelvis (ATFP), or Arcus tendinous- thickened
band of pelvic fascia running from the ischial spine to the pubic bone
and serves as a key point for fascial layer attachment.
• The ATFP originates from the pubic bone laterally (1 cm lat to
midline), pubovesical ligaments medially, and the tendinous arch of
the levator ani.
• Arcus tendineus levator ani (ATLA)- it is the aponeurotic portion of
the obturator fascia covering the obturator internus muscle. The
muscles of the levator ani attach to the ATLA.
• The inferior pelvic fascia is continuous with the obturator fascia and
fascia of the pudendal canal and covers the levator ani surface.
• The superior pelvic fascia arises from the outer stratum and
obturator fascia. It runs from the pubic symphysis laterally to the
ischial spine.
• The fascia is thinner over the muscles and organs, which allows for
more mobility.

15. Endopelvic fascia and
ATFP

17. Spaces Among Pelvic Organs
• Six potential spaces exist among the female pelvic organs.
• 1.Vesicovaginal and 2.Rectovaginal spaces are in the midline.
• The vesicovaginal space is contained by the bladder adventitia anteriorly and the vagina
posteriorly.
• This space ends where the vagina fuses with the distal urethra and at the vesicocervical
ligament (fusion of the bladder with the vagina and cervix).
• 3.Prevesical space- lies between the fascia covering the bladder and the endopelvic
fascia behind the pubis. This space extends laterally to the obliterated umbilical artery.
• 4.Retrorectal space is between the rectal fascia and the transversalis fascia over the
sacrum.
• Laterally lie the
• 5.Paravesical and 6.Pararectal spaces, which are adjacent to their respective organs.

18. Spaces among pelvic organs.

19. Spaces Among Pelvic Organs
• The pouch of Douglas, or rectouterine pouch--fold of peritoneum
(rectovaginal fold) between the uterus and rectum.
• It is bound by the uterus, posterior vaginal fornix, rectum, and
uterosacral ligaments.
• The vesicouterine pouch--fold of peritoneum (uterovesical fold)
reflected onto the bladder from the uterus at the junction of the
uterine body and cervix.

20. Ligaments
• Sacrospinous ligament- attaches from the ischial spine to the lateral border of the
sacrum and crosses in front of the sacrotuberous ligament, fusing with it medially.
• The coccygeus muscle lies over the sacrospinous ligament.
• The sciatic nerve and plexus cover the coccygeus muscle and must be avoided during
vault suspension.
• Sacrotuberous ligament- runs from the posterior iliac spine along the sacral border and
attaches to the ischial tuberosity. This attaches the ilium and ischium to the sacrum.
• The greater and lesser sciatic foramina run above and below the sacrotuberous ligament.
• In addition short and long dorsal sacroiliac ligaments connect the sacrum to the ilium
posteriorly.
• The sacrospinous ligament lies in continuity with the sacrococcygeal ligament.
• The fifth lumbar vertebrae is connected to the ilium by the iliolumbar ligament.

22. Ligaments
• The Pubovesical, Cardinal, and Uterosacral ligaments and Pubocervical
fascia are condensations of the Transversalis fascia, which help to support
the pelvic organs.
• The Pubovesical ligaments (pubourethral ligaments) are analogous to
the male puboprostatic ligaments and run from the pubic bone to the
bladder neck, providing retropubic suspension.
• They hold the bladder neck in place when it contracts and provide a
hammock-like support for the mid-urethra in continuity with the anterior
vaginal wall.

23. Pubourethral ligament

24. Broad ligament
• Formed by the peritoneum extending from the anterior and posterior surfaces of
the uterus and contains the fallopian tube and ovary.
• It lies on the posterolateral surface of the uterus attaching it to the pelvic wall.
• The uterine artery, vein, and nerves lie within the mesometrium of the broad
ligament.

25. Round ligament
• Exits at the internal inguinal ring and
crosses over the external iliac artery,
terminating in the mons pubis of the
labia majora.
• The male homolog - gubernaculum.
• Attaches the lateral uterine body
walls to the pelvic sidewalls and
contains the ovarian ligaments.

26. The infundibulo-pelvic ligament (suspensory ligament of the ovary).
• It lies behind the broad ligament and runs from the ovary to
the pelvic side wall.
• Contains the ovarian vessels and nerves.

27. Cardinal ligament and uterosacral ligaments.
• Major support.
• Lie within the parametrium.
• Nerves from the pelvic plexus travel with the vessels through the cardinal and
uterosacral ligaments.
• These structures are at risk during a hysterectomy and can lead to bladder dysfunction.
• The uterosacral (sacrouterine ligaments) originate from the greater sciatic foramen and
insert into the lateral aspect of the fascia encircling the cervix, isthmus of the uterus, and
vaginal wall.
• They contain fibrous tissue and smooth muscle--used as anchoring structures in apical
suspensions--potential for sacral nerve entrapment (s1 and s2 to s4 nerve trunks) as the
nerve crosses over the areas dorsally.
• The ureter lies lateral to the anterior portion of the uterosacral ligament (closest at the
cervix).

29. Cardinal ligament and uterosacral ligaments.
• The cardinal ligaments fuse posteriorly with the uterosacral
ligaments and stabilize the uterus, cervix, and upper
vagina.
• Cardinal lig originate from s2 to s4 and insert into the
posterolateral aspect of the pericervical fascia and lateral
vaginal wall.
• Contain the major blood vessels from the internal iliac artery.
• Ureter crosses the infundibulopelvic ligament under the ovarian
artery and lies medial to the uterine artery.
• Ureter also passes near the cardinal ligament and lies in
proximity to the cervix-prone to injury.

30. Muscles of the Pelvis.
Pelvic Sidewalls.
• Formed by the obturator internus, iliacus, psoas major and
minor, levator ani complex, and the coccygeus.
• The obturator internus- covers most of the lateral pelvic
sidewall,passes through the lesser sciatic foramen and inserts to
the greater trochanter of the femur.
• The piriformis- covers and pads the pelvic side walls
posterolaterally. Passes through the greater sciatic foramen and
inserts to the greater trochanter of the femur.
• The sacral plexus is found medially.

32. Muscles of the Pelvic Floor
Pelvic floor
• Composed of the pelvic diaphragm, which extends from the pubis
anteriorly to the coccyx posteriorly.
• Made by the broad, thin levator ani muscle-crucial role in support
and function of the urogenital viscera.
• Consists of the iliococcygeus, puborectalis, and pubococcygeus
muscles.
• Innervated by the fourth sacral nerve.(levator ani nerve).
• Blood supply-Inf gluteal artery(IIA).
• Name of each components is derived from its attachments.

34. Pelvic diaphragm

35. Puborectalis muscle
• Origin-back of the symphysis pubis and the superior fascia of the
urogenital diaphragm, runs backward alongside the anorectal
junction, and joins its paired muscle on the opposite side, to form a
U-shaped loop behind the rectum that slings the anorectal junction to
the pubis.

36. Pubococcygeus muscle
• Origin- posterior portion of the pubis and arcus tendineus
and attaches to the visceral organs and anococcygeal raphe.
• Important in visceral control by forming a sling around the
vagina and urethra, called the pubovaginal muscles.

38. Iliococcygeus muscle
• Origin-ischial spine and posterior part of the tendinous arch of
pelvic fascia.
• Insertion-last 2 segments of the sacrum, coccyx, and anococcygeal
raphe.
• It sits anterior to the sacrospinous ligament.
• Innervation solely from the levator ani nerve originating from S3,S4,
and S5.

39. • Opening of the levator ani muscle group is known as the levator
hiatus and allows passage of the urethra, vagina, and rectum.
• The levator plate is created by the fusion of the levator ani muscles
in the midline and serves as a shelf on which the viscera rests.
• Weakening--cause this plate to sag, opening the hiatus and
predisposing to pelvic organ prolapse.
• The sustained resting tone of the pelvic floor muscles supports
pelvic viscera, resists increases in intra-abdominal pressure, and is
crucial in passive control of urinary and fecal continence.
• With loss of tone from muscle or nerve injury, there is laxity in the
urogenital hiatus, which lessens the horizontal orientation of the
levator plate.

40. Vasculature
Arterial Supply
• The internal iliac arteries (hypogastric arteries) travels into the pelvic
cavity, along the posterior wall, and provide branches to the bladder,
uterus, vagina, and rectum.
• Uterine artery- Anterior branch of the internal iliac artery.
• Uterine artery branches to anastomose with the ovarian artery (direct br of
aorta) and descends to supply the cervix and vagina.
• The uterine artery passes in front of the ureter, making the ureter
vulnerable to injury during division of the uterine pedicle during a
hysterectomy.

43. Venous Drainage
• Corresponding veins, course with each arterial branch and drain into
the internal iliac veins or larger veins.
• The obturator vein lies posterior to the artery and ureter and drains
directly into the internal iliac vein.
• The superior and inferior gluteal veins, lateral sacral veins, and
middle rectal drain into the internal iliac vein.
• The clitoral veins drain into the retropubic plexus vesical plexus,
lying over the anterior portion of the bladder (in continuity with the
uterine plexus) and eventually drains in the internal iliac vein.
• The external iliac vein is a continuation of the femoral vein and
drains the inferior epigastric vein and deep circumflex iliac and pubic
veins.

44. Lymphatic Drainage.
• 3 major LN groups are associated with the pelvic vessels.
• Most lymphatic drainage passes through the internal iliac nodes and their
branches: the presacral, obturator, and internal pudendal nodes.
• External iliac nodes are divided into three chains: external, middle, and internal.
• External chain drains the anterior abdominal wall and clitoris.
• The bladder and vagina drain into the middle chain that lies over the external
iliac artery.
• Internal chain drains the lower abdominal wall, superficial and deep inguinal
nodes, bladder neck, and urethra.
• The inguinal nodes communicate directly with the internal and external iliac
chains.
• The common iliac nodes receive efferent vessels from the external and internal
iliac nodes and the pelvic ureter and drains in the lateral aortic nodes.

46. Nerves of the Pelvis
•2 TYPES - Somatic and Autonomic
innervation.
•1.Somatic includes sensory and motor
functions and relates to the external
genitalia and the pelvic floor.
•2.Autonomic provides sympathetic and
parasympathetic nerves supply to the pelvic
organs.

47. 1.Somatic innervation-Sacral plexus.
• Formed from the ventral rami of L4-L5 and S1-S4.
• Lies on the piriformis muscle deep to the endopelvic fascia and
posterior to the internal iliac vessels.
• Exits the pelvis through the greater sciatic foramen immediately
posterior to the sacrospinous ligament (ssl) and can be injured
during a sacrospinous ligament colposuspension.
• Supplies motor and sensory innervation to the posterior thigh
and lower leg.

48. 1.Somatic innervation- Sacral plexus.
• Exaggerated lithotomy position may stretch the tibialis anterior
muscle, innervated by the L4-S1 roots, through the sciatic and
ultimately deep peroneal nerves, which can lead to foot drop.
• Pelvic and perineal branches of the sacral plexus include the
posterior femoral cutaneous nerve (S2-S3)--passes through the
greater sciatic foramen and has a sensory branch to the
perineum.
• They travel on the pelvic surface of the levator ani, innervating
these muscles as well as the striated urethral sphincter.

49. 1.Somatic innervation- Pudendal nerve.
• Arises from S2-S4 just above the sacrotuberous ligament
and ischiococcygeus, passes through the greater sciatic
foramen, and crosses the piriformis, ischiococcygeus, and
Sacrospinous ligament close to where it attaches to the
ischial spine.
• Vulnerable to injury during sacrospinous lig fixation
surgery.
• Runs medial to the internal pudendal vessels as they travel
through the lesser sciatic foramen into alcock canal.

50. 1.Somatic innervation- Pudendal nerve.
• Branches.
• (1) Inferior rectal nerve.
• (2) Perineal nerve.
• (3) Dorsal nerve of the clitoris.
• The perineal branch divides into posterior labial branch(labium
majus), superficial and deep transverse perineal muscles,
external anal sphincter, and levator ani.
• The pudendal branches carry efferent impulses to muscles of
the pelvic floor and proprioceptive afferent signals and
sensation from the urethra.
• The pudendal nerve mediates perineal pain.

51. Pudendal nerve.

52. 1.Somatic innervation.
• Additional cutaneous innervation of the mons and labia is
derived from the ilioinguinal nerves (L1), the genitofemoral
nerves (L1 and L2), and of the perineum through the posterior
femoral cutaneous nerve from the sacral plexus (S1-S3).

53. 2.Autonomic Innervation- Sympathetic.
• Arises from preganglionic fibers at the T10-T12 level.
• Supplies ovaries and fallopian tubes through sympathetic fibers
travelling along the ovarian vessels.
• Body of the uterus and cervix supplied by hypogastric plexus,
accompanying branches of the iliac vessels.
• Superior hypogastric plexus arises from the aortic plexus below the
aortic bifurcation at L5.
• The right and left pelvic (hypogastric) plexi lie near to the bladder
base, forms the vesical plexus and uterovaginal plexus, which sends
fibers through the broad ligament.

54. 2.Autonomic Innervation- Parasympathetic.
• Lie deeper to the sympathetic fibers within the
intermediate stratum and arises from S1-S3 segments.
• Controls smooth muscle function of the bladder and
anal sphincter systems (smooth muscle of the internal
anal sphincter and striated muscle of the external anal
sphincter).
• Pain from cervix is mediated through the
parasympathetic afferent nerves passing backward to
S1-S2.

55. Pelvic organ support.
De-lancey level I support-
• Suspends the uterus and upper third of vagina to the sacrum and
lateral pelvic sidewall.
• Level 1 is composed of parametrium and paracolpium.
• The uterosacral and cardinal lig forms the parametrium.
• Paracolpium is a long sheet of tissue that suspends the superior
portion of vagina by attaching it to the pelvic wall.
• Broad and round ligaments- no significant role in pelvic organ
support.
• Loss of level 1 contributes to the prolapse of the uterus or
vaginal apex.

56. Pelvic organ support.
• Level II support - paravaginal attachments of the
middle third of vagina laterally to the superior fascia
of the levator ani muscle and ATFP.
• Anterior vaginal wall prolapse results from loss of
level II support (anterior vaginal wall support).

57. Pelvic organ support.
• Level III support is created by the distal vagina attachments to the
levator muscles laterally, anteriorly to the urethra, and posteriorly to
the perineal body.
• Level III support provides foundation to the urethra, and disruption
leads to urethral hypermobility.

58. level I support are
oriented vertically and
suspend the uterus
and upper vagina.
Level II support is more
horizontal in its
orientation and is
attached to the mid-
vagina.
Distally, level III support
fuses directly into support
structures.

61. Urethra.
• 4 cm long and 6 mm in diameter.
• Suspended beneath pubis by the posterior pubo-urethral ligaments
and anteriorly by the suspensory ligaments of the clitoris.
• Eum is 2.5 cm behind the glans clitoris and 1 cm anterior to the
vaginal opening.
• Urethral wall-
• 1.Outer, circular muscular layer.
• 2.Inner, longitudinal mucosal layer- lines the lumen, is continuous
with the bladder mucosa and constitutes the involuntary urethral
sphincter.
• Internal sphincter- continuation of detrusor muscle and is made of
smooth muscle, under involuntary or autonomic control.

62. Urethra.
• The external sphincter is anatomically separate from the striated
muscles of the anterior pelvic floor.
• The longitudinal fibers shorten the urethra and increase the
diameter during voiding.
• Distal two-thirds of the urethra- voluntary sphincter(striated
muscle).
• At the most proximal portion (mid-urethra) it forms a
horseshoe around the urethra.
• Closing pressure is highest at mid urethra.

63. Urethra.
• Lateral sides of the urethra has muscle fibers continuous with the anterior and
lateral walls of the vagina (urethral compressor).
• When they contract, the urethra closes against the anterior vaginal wall.
• The additional fibers surrounding the urethra and vagina compose the
urethrovaginal sphincter. Contracts to tighten the urogenital hiatus.
• Pubococcygeus runs along the urethra bilaterally--increases resistance in urethra.
• Periurethral glands- many, when obstructed--urethral diverticula or cysts.
• Most prominent are skene glands (homologous with the prostate), open distally
just inside the meatus.
• The mucosa and submucosa are primarily responsible for urethral closure
pressure and are estrogen dependent.

64. Urethra.

65. Urethra.

66. Urethra.
• Arterial supply- primary- vaginal artery.
• Some from the inferior vesical artery and internal pudendal
arteries.
• Venous drainage- the inferior, middle, and superior vesical
veins, as well as the clitoral plexus into the internal pudendal
veins.
• Lymphatics-
• Distal one-third of the urethra (anterior urethra)- superficial
and deep inguinal LN.
• Proximal two-third (posterior urethra) - iliac and obturator
LN.

68. Laparoscopic view of female pelvis.

71. Medial most-ureter

75. Thankyou