Uro gynaecology- anatomy- pelvic floor

1. Surgical
Anatomy of the
Pelvic floor
Dept of Urology
Govt Royapettah Hospital and Kilpauk Medical College
Chennai
1

2. Moderators:
Professors:
• Prof. Dr. G. Sivasankar, M.S., M.Ch.,
• Prof. Dr. A. Senthilvel, M.S., M.Ch.,
Asst Professors:
• Dr. J. Sivabalan, M.S., M.Ch.,
• Dr. R. Bhargavi, M.S., M.Ch.,
• Dr. S. Raju, M.S., M.Ch.,
• Dr. K. Muthurathinam, M.S., M.Ch.,
• Dr. D. Tamilselvan, M.S., M.Ch.,
• Dr. K. Senthilkumar, M.S., M.Ch.
Dept Of Urology, KMC and GRH, Chennai 2

3. Pelvic Floor
The bony pelvis form a
basin whose bottom is
covered by what is called
as the pelvic floor.
Dept Of Urology, KMC and GRH, Chennai 3

4. Sciatic Foramens
• 2 ligaments and 2 foramens
• Sacrospinous ligament: From sacrum to
ischial spine
• Sacrotuberous ligament: From sacrum
to ischial tuberosity
• Greater schiatic foramen: Above
sacrospinous ligament
• Lesser sciatic foramen: Below
sacrospinous ligament
Dept Of Urology, KMC and GRH, Chennai 4

5. Sacrotuberous and Sacrospinous ligaments
Dept Of Urology, KMC and GRH, Chennai 5

6. Pelvic Outlet
The pelvic outlet is
diamond-shaped, with the
apices defined by bony
landmarks—
the symphysis pubis
anteriorly,
the ischial tuberosities
laterally,
and the tip of the coccyx
posteriorly.
Dept Of Urology, KMC and GRH, Chennai 6

7. Pelvic Outlet
• It can be further dissected
into:
• Urogenital triangle/Anterior
triangle defined by the
symphysis and two
tuberosities and
• Anal triangle/posterior
triangle defined by the coccyx
and two tuberosities
Dept Of Urology, KMC and GRH, Chennai 7

8. Pelvic Floor
• The pelvic floor is a compound structure consisting of
• Pelvic floor muscles,
• Fascia and ligaments.
It is enclosed by the bony scaffolding of the pelvis, formed by 2
innominate bones which articulate with the sacrum posteriorly and
each other anteriorly
Dept Of Urology, KMC and GRH, Chennai 8

9. Pelvic Floor Muscles
• Pelvic diaphragm
• Piriformis
• Obturator Internus
Dept Of Urology, KMC and GRH, Chennai 9

10. Obturator Internus and Piriformis
Dept Of Urology, KMC and GRH, Chennai 10

11. Pelvic Diaphragm
Dept Of Urology, KMC and GRH, Chennai 11

12. Levator Ani
Subdivided, from medial to lateral into
• Puborectalis,
• Pubococcygeus, and
• Iliococcygeus.
Dept Of Urology, KMC and GRH, Chennai 12

13. Puborectalis and Pubococcygeus
• Originate from the inner
aspect of the pubic rami on
either side of the midline at
the level of the pubic
symphysis.
• The muscle fibers pass
laterally to the vagina and
rectum, creating a U-shaped
sling surrounding the genital
hiatus medially.
Dept Of Urology, KMC and GRH, Chennai 13

14. Iliococcygeous
• Origin from arcus tendineus
levator ani or muscle white
line.
• The muscles of the
iliococcygeous pass laterally to
the pubococcygeus muscles,
fanning out to create the
pelvic floor posteriorly and
laterally.
• Insertion into the lower aspect
of lateral sacrum.
Dept Of Urology, KMC and GRH, Chennai 14

15. Coccygeus/Ischiococcygeus
• The coccygeus is also termed
the ischiococcygeus muscle.
• It is attached medially to the
lateral margins of the coccyx
and fifth sacral segment and
laterally to the ischial spine.
Dept Of Urology, KMC and GRH, Chennai 15

16. Levator plate
• The levator plate is formed by the
midline fusion of the levator ani
muscles between the rectoanal
junction and the coccyx.
• The uterus and cervix, as well as
the upper two-thirds of the vagina,
are suspended over the levator
plate.
• Most important source of indirect
mechanical support for these
organs.
Dept Of Urology, KMC and GRH, Chennai 16

17. Perineal Body
• The perineal body, located
under the pelvic floor, is a
fibromuscular mass of tissue
between vagina and anus in
females, bulb and anus is males.
• It is formed by the attachments
of several muscles.
Dept Of Urology, KMC and GRH, Chennai 17

18. Perineal Body - Muscles
• Superficial transverse perineus
• Bulbospongiosus
• Sphincter urethrae in the male
• Sphincter urethrovaginalis and deep transverse perineus muscles in
the female
• Superficial part of the external anal sphincter
• Levator prostatae and pubovaginalis of the levator ani
Dept Of Urology, KMC and GRH, Chennai 18

19. Fibre types
• Majority type I (slow twitch) muscle fibers that maintain a constant
resting tone over time.
• Also contains a smaller proportion of type II (fast twitch) fibers,
permitting them to respond quickly during sudden increases in intra-
abdominal pressures.
• Contraction of the pelvic diaphragm closes the genital hiatus and
provides a horizontal levator plate on which the pelvic viscera lie.
Dept Of Urology, KMC and GRH, Chennai 19

20. Pelvic Floor Muscles
Dept Of Urology, KMC and GRH, Chennai 20

21. Foramen and Hiatus
• Obturator foramen
• Urogenital hiatus
• Rectal Hiatus
Dept Of Urology, KMC and GRH, Chennai 21

22. Fasciae
The pelvic fascia is divided into:
• Parietal pelvic fascia, which forms
the coverings of the pelvic
muscles, and
• Visceral pelvic fascia, which forms
the coverings of the pelvic organs
and their neurovascular supply
Dept Of Urology, KMC and GRH, Chennai 22

23. Parietal Pelvic Fascia
Forms the coverings of the pelvic muscles,
• Mechanically dense matrix of connective tissue consisting
predominantly of collagen fibers
• They coalesce into thick bundles that are then interwoven into a
strong, three-dimensional sheet.
Dept Of Urology, KMC and GRH, Chennai 23

24. Parietal Pelvic Fascia
It includes
• Obturator fascia,
• Fasciae over piriformis, and
• Fasica over levator ani (the pelvic diaphragm) and
• Presacral fascia.
Dept Of Urology, KMC and GRH, Chennai 24

25. Arcus Tendineus Levator Ani
• Thickened portion of
Obturator fascia.
• Anterior – Pubic rami,
Posterior- Ischial spine.
• Origin of iliococcygeus
muscle
Dept Of Urology, KMC and GRH, Chennai 25

26. Arcus Tendineus Fasciae Pelvis
• Condensation of obturator fascia and the
visceral fascia enveloping the anterior and
posterior vagina.
• Medial to and runs nearly parallel to the
arcus tendineus levator ani.
• Anterior- Pubic rami,
• Posterior- Joins arcus tendineus levator ani
• Provides the lateral anchoring sites for the
anterior vaginal wall and posterior vaginal
wall.
Dept Of Urology, KMC and GRH, Chennai 26

27. Presacral Fascia
• Part of the parietal layer of pelvic fascia.
• Located posterior to the retrorectal
space.
• Thick and strong, it covers the concave
surface of the sacrum.
• Multiple veins, several arteries, and
nerves reside beneath this fascia.
Dept Of Urology, KMC and GRH, Chennai 27

28. Visceral fascia/Endopelvic fascia
• It is a loose, three-dimensional meshwork of collagen, elastin, and
smooth muscle with a richer vascular supply.
• Connective tissue that encapsulates the individual organs within the
pelvis.
• Named according to the organ it covers, such as vesical, rectal, or
prostatic.
• Where the organ passes through the pelvic floor, the visceral fascial
capsule fuses with the adjacent parietal fascia of the floor.
Dept Of Urology, KMC and GRH, Chennai 28

29. Visceral / Endopelvic fascia
Dept Of Urology, KMC and GRH, Chennai 29

30. Endopelvic Fascia-Specialisations
Dept Of Urology, KMC and GRH, Chennai 30

31. Uterosacral Ligament
• Fan shaped origin from sacrum
S2-S4 narrowing to its smallest
width just proximal to the cervix.
• This broader attachment
disperses the suspensory forces
acting on the uterosacral
ligament
Dept Of Urology, KMC and GRH, Chennai 31

32. Rectovaginal septum or Denonvillier’s Fascia
• Rectovaginal septum separates the
rectum from the posterior vaginal
wall.
• Extends from one ischial spine to
the other.
• Attached inferiorly to the perineal
body (perineal center) and floor of
the pelvis.
• Bilaminar; potential space (of
Proust) lies between the two
laminae.
Dept Of Urology, KMC and GRH, Chennai 32

33. Cardinal Ligament/Transverse Cervical
Ligament
• Condensation of the endopelvic fascia.
• It is a thickening around the uterine
vessels.
• Extends from the sidewall of the pelvis
laterally to the cervix.
Dept Of Urology, KMC and GRH, Chennai 33

34. Pubocervical Fascia
• Thickened anterior portion of the
fibromuscular coat that surrounds the
vaginal epithelium.
• Extends from underneath the urethra,
laterally to the fascial white lines, and
posteriorly to the pericervical ring of
endopelvic fascia around the cervix.
• Forms a horizontal hammock upon which
the bladder rests.
• Purpose of the intact pubocervical fascia
is to prevent cystocele
Dept Of Urology, KMC and GRH, Chennai 34

35. Pubocervical Fascia
Dept Of Urology, KMC and GRH, Chennai 35

36. Hammock Hypothesis
• Distal portion of the
pubocervical fascia
supports the urethra
and UV junction.
• Provides back drop
against which urethra is
compressed during
straining.
Dept Of Urology, KMC and GRH, Chennai 36

37. Paravaginal Defects
Dept Of Urology, KMC and GRH, Chennai 37

38. DeLancey Classification
• DeLancey introduced the concept of dividing the connective tissue
support in the pelvis into three levels.
• Levels I, II, and III represent apical, middle, and distal vaginal support,
respectively
Dept Of Urology, KMC and GRH, Chennai 38

39. DeLancey Support
• Level I - Cardinal and uterosacral
ligaments
Dept Of Urology, KMC and GRH, Chennai 39

40. DeLancey Support
• Level II is the support of the
midvagina-
• Produced by the lateral attachments
of the anterior and posterior
endopelvic fascia to the pelvic
sidewalls. (ATFP, ATLA)
Dept Of Urology, KMC and GRH, Chennai 40

41. DeLancey Support
• Level III support results from the
fusion of these same sheets with
the pubic symphysis anteriorly and
perineal body posteriorly. (Perineal
membrane and Urogenital
diaphragm)
Dept Of Urology, KMC and GRH, Chennai 41

42. Materials Used for Midurethral slings
Dept Of Urology, KMC and GRH, Chennai 42

43. Ideal Sling Material
• Chemically and physically inert,
• Sterile,
• Noncarcinogenic,
• Mechanically strong,
• Not physically modified by the body tissue,
• Readily available,
• Inexpensive, and have
Dept Of Urology, KMC and GRH, Chennai 43

44. Ideal Sling Material
• Once healed the graft should restore normal anatomy and function to
the pelvis,
• Be equally durable to autologous tissue.
• In addition the material should remain long enough for incorporation
of the surrounding host tissue.
• It should withstand mechanical stress and shrinkage, be pliable and
easily manipulated during surgery, causing minimal surrounding
reaction.
Dept Of Urology, KMC and GRH, Chennai 44

45. Types
• Natural Biomaterials
• Synthetic Biomaterials
Dept Of Urology, KMC and GRH, Chennai 45

46. Natural Biomaterials
• Autologous grafts (tissue harvested from the patient),
• Allografts (tissue obtained from a source other than the recipient but
from the same species), and
• Xenografts (tissue obtained from a species different from the
recipient).
Dept Of Urology, KMC and GRH, Chennai 46

47. Autologous grafts
The commonly used materials here are
• Rectus fascia and
• Tensor fascia lata.
Dept Of Urology, KMC and GRH, Chennai 47

48. Rectus Fascia
• Easily harvested, even in patients with multiple abdominal
operations.
• Durable and rarely causes urethral erosion.
• Disadvantages: longer operative time, higher surgical morbidity,
postoperative pain and longer recovery.
• Rectus fascia may be scarred and thickened owing to prior operations.
Dept Of Urology, KMC and GRH, Chennai 48

49. Fascia Lata
• Easily obtainable long graft.
• Generally unscarred and of uniform thickness.
• The length means it is easier to achieve adequate tension on the
sling.
• As there is no abdominal incision, recovery time is less, and there is
no risk for abdominal hernias.
• Disadvantage: Longer operative time.
Dept Of Urology, KMC and GRH, Chennai 49

50. Allograft
• Cadaveric human fascia lata, dura or dermis has been used.
• It decreases operative time and avoids the possible morbidity
associated with a second surgical site.
• Risk of infectious disease transmission, in particular Creutzfeldt-Jakob
disease and other prion transmission-related illnesses
Dept Of Urology, KMC and GRH, Chennai 50

51. Xenograft
• Porcine dermis and small intestine submucosa has been used.
• Acellular graft made up of collagen and elastin fibers which provide a
matrix on which new tissue and cells are supported.
• Comparatively less immune response.
Dept Of Urology, KMC and GRH, Chennai 51

52. Synthetic Biomaterials-Advantages
• Lack of potential infectious disease transmission
• High tensile strength,
• Readily available,
• Cost-effective,
• Do not require harvesting, therefore reduce operative risks.
Dept Of Urology, KMC and GRH, Chennai 52

53. Synthetic Mesh Types
Classified on the basis of pore size and the filamentous nature of the
material.
• Type I meshes are macroporous (>75mm) and monofilament.
• Type II meshes are microporous with pore sizes less than 10 mm.
• Type III meshes are macroporous meshes with multifilamentous
components.
• Type IV meshes are ‘coated’ biomaterials that have submicronic (less
than 1 mm) pore size.
Dept Of Urology, KMC and GRH, Chennai 53

54. Polyethylene Terapthalmate Mesh
• First used mesh, not used now.
• Long chain polymer of the monomer ethylene,
• Classified into several categories based on density and branching.
• Merisilene was a famous Type III mesh.
• With the introductionof polypropylene mesh, it has been abandoned.
Dept Of Urology, KMC and GRH, Chennai 54

55. Polypropylene Mesh
• It is a thermoplastic polymer which has a variety of applications
including food packaging and car components.
• When used in a mesh, this material is composed of loosely woven
strands of synthetic material.
• If pore size is greater than 80 μm supposedly allows the passage of
macrophages which may result in improved host tissue ingrowth.
• Eg: TVT, Ethicon
Dept Of Urology, KMC and GRH, Chennai 55

56. Polytetrafluoro ethylene (PTFE)
• It is a microporous material. Classified as Type II mesh
• Soft and pliable multifilament with fewer adhesions and a less
obvious inflammatory response.
• Eg: Gore-Tex
• Not widely used to problems of erosion and high rejection rates
(37.5%)
Dept Of Urology, KMC and GRH, Chennai 56

57. Thank You
Dept Of Urology, KMC and GRH, Chennai 57