PROCEDURE
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This is the procedure for the female, for male donor instructions select male instructions

1. Turn your donor to the supine position and move the lower limbs to the sides to allow view of the external genitalia.

2. Examine the female external genitalia organization.
    (Figure432) (Netter358) (Photo4022)

Mons pubis - This is formed by a fat pad in the superficial fascia anterior to the pubic symphysis, most prominent following puberty and less prominent post-menopause, as the connective tissue volume in this region is estrogen sensitive.

Labia majora - These are longitudinal folds of skin extending posteriorly from the pubic mons. Each labia majora has an exterior pigmented skin surface and an interior smooth skin surface.

The round ligament of the uterus which exited through the superficial inguinal ring separates into multiple fibers which anchor into the mons pubis and labia majora.

Labia minora - Retract the labia majora laterally to observe two folds/flaps of skin lateral to the vaginal opening. These extend posteriorly and obliquely. The prominence of these tissue flaps is highly variable between individuals, ranging from a distinct flap to a negligible elevation.

Vulvar vestibule - This is the region demarcated between the labia minora. The urethra and vagina open into this space.

Clitoris - The glans of the clitoris is present anterior to the vaginal opening, with the upper part of the labia minora passing anterior to the clitoris fusing with the labia minora of the other side.

The glans of the clitoris is only the externally visible part of the clitoris, the crus ('legs') of the clitoris extend under the skin along the perineum parallel to the inferior pubic rami nearly the full length of the rami.  Additional erectile tissue also extends from the glans of the clitoris under the skin the length of the labia minora on each side of the vaginal opening (called the 'bulb of the vestibule').

Vaginal opening - The midline opening into the muscular canal of the vagina. 

External urethral orifice - This orifice is present approximately 2cm posterior to the clitoris immediately anterior to the vaginal opening. This is difficult to observe in an embalmed donor due to heightened tissue density with embalming, but review the approximate location.

The urethral opening is the entry point for a Foley catheter, to access the bladder for drainage.

3. Observe the pelvic organs and their position relative to the pelvic bony architecture.
    (Figure413) (Netter344) (Netter346) (Netter345)
    (Photo4055)

Urinary bladder - Immediately posterior to the pubic symphysis is the bisected urinary bladder (bisected by the MS2 class during urinary systems study). Typically, fluid content has emptied and the bladder is in a completely relaxed state flattened against the anterior wall.  The superior and lateral edges of the bladder are practically invisible due to this flattening.

Rectum - Anterior to the sacrum/coccyx will be the rectum. Depending on where your viscera removal cut was made there may be a small length of colon still connected to the rectum. The rectum 'start' approximately the level of the sacral promontory (reference sources vary in the anatomic definition of the start of the rectum, thus it is approximate).

Vagina - Situated between the bladder and the rectum is the muscular tube of the vagina. This is a subperitoneal organ and thus too inferior to palpate from the peritoneal side.

Uterus - Superior to the vagina is the uterus visible posterior to the bladder and anterior to the rectum. The wall of the uterus is significantly thicker than that of the vagina, and typically sits in a sharply anteverted angle relative to the vagina. The anteverted and antiflexed position 'tilts' the fundus of the uterus towards the bladder superior surface. The upper section of the uterus is the fundus while the lower region is the body.

In 20-30% of individuals the uterus is retroflexed to some degree, thus some donors will have a uterus that may have greater or lesser antevertion tilt.

Many women will have had a hysterectomy (~30-50% of women above the age of 60). Thus, you may find all or part of the uterus absent in some individuals. Where possible, surgeons will leave at least one ovary to control hormonal balance in the patient.

Ovary - Just lateral to the uterus, attached to the posterior side of the mesentery connecting the uterus to the lateral wall, is the ovary. Typically this is an oval shaped irregular surfaced solid structure. In the elderly it is approximately 2-3cm in size. In younger individuals it is larger at approximately 3-5cm. 

4. Trace the peritoneum from the anterior wall across to the posterior wall of the abdomen as it 'drapes' over the pelvic organs forming several spaces/grooves.
    (Figure413) (Netter344) (Netter346) (Photo4055)

Begin by sliding fingers down the inner wall of the anterior abdominal wall and across onto the superior surface of the bladder. Due to collapse of the bladder, the demarcation between anterior abdominal wall and bladder lacks a distinct groove.

Vesicouterine fossa (or pouch) - Follow the peritoneum across the bladder where it dips inferiorly before reflecting superiorly up onto the uterus. The space formed by this inferior to superior reflection of peritoneum from the bladder to the uterus is the  vesicouterine fossa.

Rectouterine fossa (or pouch) - Follow the peritoneum surface over the uterus where it turns inferiorly to follow the posterior side of the uterus before reflecting superiorly up onto the rectum. The space formed by the inferior to superior reflection of peritoneum from the uterus to rectum is the rectouterine pouch (also called the pouch of Douglas in older literature).

If your donor has had a hysterectomy, in the absence of the uterus the demarcation between the vesicouterine and rectouterine pouches is not present and the peritoneum continues across where the uterus was posteriorly to the rectum.

Broad ligament - Use your fingers to trace the peritoneum on the anterior and posterior sides of the uterus as it extends as sheet laterally out to the pelvic wall. This double layer of peritoneum spanning from the uterus to the pelvic wall laterally is the broad ligament of the uterus. The ovary is attached to the posterior surface of the board ligament.

5. Identify the regions of the broad ligament of the uterus spanning from the left and right sides of the uterus across to the pelvic wall.
    (Figure414) (Netter355) (Netter357) (Netter346)
    (Photo4055) (Photo4056)

Mesosalpinx (the mesentery of the uterine tube) - This is the superior edge of the broad ligament that covers and supports the uterine tubes.

Mesovarium (the mesentery of the ovaries) - The ovaries hang partly away from the posterior side of the broad ligament, attached to the broad ligament by a small extension of posterior peritoneum called the mesovarium. The mesovarium extends over the ovaries in an incompletely cover.

Mesometrium (the mesentery of the uterus) - This is the region below the attachment of the mesovarium and includes all of the peritoneum that continues over the uterus. 

The pelvic organs have several additional supportive 'ligaments' in the endopelvic fascia, which are really just thickenings of the connective tissue between organs and pelvic wall. 

Cardinal (Transverse Cervical) Ligament: The fascia just inferior to base of the broad ligament is slightly thicker called the cardinal (or transverse cervical) ligament. While not yet visible, this region also contains the uterine artery supplying blood to the uterus and forms a lateral support to the uterus helping to prevent prolapse.

Uterosacral ligaments: These are 'arches' spanning from the uterus to each side of the rectum attaching to the sacrum. The uterosacral ligament attaches to the cervical region of the uterus and provides stability to the uterus position in the pelvic cavity helping to prevent uterine prolapse.

6. Examine the anterior side of the broad ligament of the uterus for the round ligament of the uterus.
    (Figure414) (Netter355) (Photo4056)

The round ligament traverses inside the broad ligament (sandwiched between the peritoneum sheets) and is typically visible through the peritoneum or discernable by palpating.

The round ligament of the uterus is a rod of dense connective tissue attaching at the junction between the uterus and the uterine tube, and extending out to pass through the deep inguinal ring. 

The round ligament of the uterus continues through the inguinal canal and superficial inguinal ring. Upon exiting the superficial ring the fibers of the ligament spread to anchor into the tissue of the labia majora.

7. Find the superior free edge of the board ligament which holds the uterine tube. 
    (Figure414) (Netter355) (Photo4056)

The uterine tube is connected to the uterus proximally and the diameter of the uterine tube expands at the distal end forming the infundibulum.

Delicate finger-like projections of tissue, the fimbriae, extend from the infundibulum approaching the ovary. However, the ovary is not directly connected to the fimbriae.

8. Sandwich the broad ligament between your fingers in the region between the ovary and uterus to feel the stiffer cord like structure of the proper ligament of the ovary.
    (Figure414) (Netter355) (Photo4056)

Reflecting the uterine tubes anteriorly and holding the ovary can extend this ligament making it easier to visualize.

The proper ligament of the ovary is a fibromuscular tissue that connects the inferior pole of the ovary to the junction between the uterus and the uterine tube.

9. Observe on the superior pole of the ovary (opposite to the connection of the proper ligament of the ovary), a fold of peritoneum extending laterally out to the pelvic wall.
    (Figure414) (Netter355) (Netter382) (Photo4056)

This peritoneal fold is the suspensory ligament of the ovary, which contains the ovarian (gonadal) blood vessels, nerves, and lymphatic vessels.

Recall, in females the specific term for the generic gonadal artery is the ovarian artery.

10. Return to the aorta where you had identified the ovarian arteries in the previous labs and follow the ovarian artery inferiorly all the way along to the ovary via the suspensory ligament of the ovary.
    (Netter346) (Netter382) (Photo4056)

In a previous lab connections of the kidneys were transected, which often results in transection of the ovarian vasculature prior to the junction with the aorta and vena cava. So you may only have a section of the suspensory ligament with the vasculature close to the ovaries intact.

The ovarian artery provides branches to the uterine tubes, and commonly, but not always, continues across to the superior part of the uterus.

SWAP POINT #1: At this point, swap with your pre-identified table (Laboratory Swap Map). containing a donor of the opposite sex and go through the steps on the appropriate instruction set until you reach the swap point in those instructions. Then return to your donor to continue steps below.

11. Just inferior to the level of the pelvic brim cut though both ovarian arteries and round ligaments of the uterus.

12. Separate the peritoneum between the uterus and the bladder so you can push your hand several inches inferiorly into the loose fascia.

The peritoneum can be strong so you may need to start with a lateral incision using a scalpel through into the fascia before you can blunt dissect to separate.

13. Separate the peritoneum between the uterus and the rectum so you can push your hand several inches inferiorly into the loose fascia.

The peritoneum can be strong so you may need to start with a lateral incision using a scalpel through into the fascia before you can blunt dissect to separate.

14. Separate the broad ligament from its pelvic wall attachment.

15. At the level inferior to the uterus transect through the vagina (i.e. between the pelvic diaphragm and cervix).

CAUTION: Since you are working almost vertically into the pelvis be extremely careful of cutting yourself with the use of the scalpel as your view of where the blade is located is limited.

Progressively reflect the uterus/vagina organ block while making small cuts through the tissue to separate the uterus.

The uterus organ organ block with ovaries attached should now be free of any major connections to the pelvic cavity and small endopelvic fascia can be separated using fingers with blunt dissection.

16. Make a mid-sagittal incision through the vagina and uterus separating into two halves.
    (Figure417) (Netter355) 

The uterus is situated at an almost 90 degree anterior tilt relative to the vagina and curving anteriorly (i.e. in the anteverted/anteflexed position).

17. Examine the cut surfaces of the vagina and examine the interior structures.
    (Figure417) (Netter355) 

The vagina is a fibromuscular tube with the inferior end open to the outside world (transected in the steps above) and the superior end connecting to the uterus.

The wall is thinner than that of the uterus and contains a higher proportion of elastic connective tissue as part of the muscularis layer.

Observe the superior end and note how the wall of the vagina connects to uterus such that part of the cervix protrudes into the vagina forming a recess around the edges of the cervix. This recess are the vaginal fornices.

18. Examine the cut surfaces of the uterus and examine the interior structures.
    (Figure417) (Netter355) 

Identify the general regions of the uterus. The uterus is divided up into the fundus (rounded region superiorly), the body (central part of the organ), the isthmus (narrow portion superior to the cervix) and the cervix (narrow region protruding partially into the vagina).

Observe the thick muscular layer, the myometrium, which makes up most of the wall of the uterus. The endometrium lining the internal surface is typically difficult to see with the naked eye (refer to your Virtual Histology guide for more microscopic detail).

Observe the muscular wall of the cervix and cervical canal. Note how the cervix protrudes into the vagina forming the vaginal fornices around the edges of the cervix.

This transitional zone at the cervix is the region of tissue from which cells are collected in a PAP smear. Collected cells are examined histologically for indications of pre-cancerous and cancerous processes that could be occurring in the uterus.

Observe the narrowing leading into the fallopian tubes and the continuation of the tubes all the way to the infundibulum end containing the fimbriae.

SWAP POINT #2: At this point, swap with your pre-identified table (Laboratory Swap Map) containing a donor of the opposite sex and review through the steps on the appropriate instruction set for the second block of dissection work  (note the dissection will have been performed by the other table so you will be examining the exposed structures at their table). Then return to your donor to close up with he steps below.

PROCEDURE - PUDENDAL

19. Turn the donor over to prone position

20. Partially spread the donor's lower extremities as this will make access into the anal triangle easier.
    (Figure549)

Placing the wood block between the legs may assist in keeping the donor's lower extremities spread while working in this region.

The anal triangle is an region formed by imaginary lines from the left and right ischial tuberosity and the midline coccyx. The anus, ischiorectal fat, and inferior rectal branches of the pudendal neurovascular bundle are the important structures in the region.

21. Identify the sacrotuberous ligament between the hard point of the ischial tuberosity and the edge of the sacrum.
    (Figure504) (Netter493) (Photo5048)

Pressing your fingers onto the ligament you will feel a slight 'bounce' to the tight ligament which can give a guide to where the ligament is positioned.

The triangularly shaped sacrotuberous ligament is attached to the ischial tuberosity and spans to the sacrum. Only limited movement is possible between these bony points. The ligament primarily serves to stabilize the sacroiliac joint and as a shock absorber during locomotion.

22. Clean any remaining fascia from the posterior surface of the sacrotuberous ligament to define the borders of the ligament.
    (Figure504) (Netter493) (Photo5048)

The pudendal nerve courses deep to the sacrotuberous ligament, which must be severed in order to view the nerve.

23. Insert a blunt probe just deep to the sacrotuberous ligament passing from superior to inferior.
    (Photo4020)

24. Using the blunt probe as a guide, transect the sacrotuberous ligament in the middle.
    (Photo4031)

Transecting the sacrotuberous ligament exposes the area of the lesser sciatic foramen where we will observe the pudendal branches.

25. Reflect the cut ends of the ligament laterally and medially exposing the fascia below.

26. Blunt dissect into the fascia below the sacrotuberous ligament to find the pudendal neurovascular bundle.
    (Figure503) (Netter493) (Photo4021)

The pudendal neurovascular bundle (nerve, artery and vein) exits the pelvis through the greater sciatic foramen, inferior to the piriformis muscle and medial to the sciatic nerve. 

The pudendal neurovascular bundle travels deep to the sacrotuberous ligament and superficial to the sacrospinous ligament (i.e. through the lesser sciatic foramen you opened by cutting the sacrotuberous ligament).

The pudendal neurovascular bundle bifurcates into rectal (to the anus) and perineal (to the perineum) branches as it passes out from under the sacrotuberous ligament. 

We will not dissect the nerve further than the nerve's passage deep to the sacrotuberous ligament. This location, as the nerve courses towards the perineum/anal regions, is a common target for local anesthesia for OBGYN procedures.

The bifurcation of the nerve can occur prior to emerging from the greater sciatic foramen, in which case you will see two neurovascular bundles passing deep to the sacrotuberous ligament (one turns to the anus and a second towards the perineum).

The perineal branch continues anteriorly to the medial side of the ischial tuberosity and then to the perineum. The location just distal to the ischial tuberosity is the approximate target for injecting anesthesia in a pudendal nerve block. Most commonly, the needle approach is from the inferior aspect using the ischial spine as a palpable landmark. The needle is inserted parallel to the plane of the urogenital triangle in order to anesthetize the main branch of the pudendal nerve innervating the urogenital region. (Figure444)

27. Place the excised reproductive organs into the biohazard bag with the heart/lungs in the organ box when complete for the day.

CHECKLIST

Return to the main pelvis page HERE for the combined male/female checklist.