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CHAPTER 1  Surgical Anatomy of the Female Pelvis

point of division between these two structures. The term parametrium refers to all the tissue that attaches to the uterus (both cardinal and uterosacral ligaments), and the term paracolpium is used to describe that portion that attaches to the vagina (cardinal ligament of the vagina). The uterosacral ligament portion of the parame- trium is composed predominantly of smooth muscle, the autonomic nerves of the pelvic organs, and some intermixed connective tissue and blood vessels, whereas the cardinal ligament portion consists primarily of peri- vascular connective tissue, nerves, and pelvic vessels. Although the cardinal ligaments are often described as extending laterally from the cervix to the pelvic wall, in the standing position, they are almost vertical as one would expect for a suspensory tissue. Near the cervix, the uterosacral ligaments are discrete, but they fan out in the retroperitoneal layer to have a broad, if some- what ill-defined, area of attachment over the second, third, and fourth segments of the sacrum. The utero- sacral ligaments hold the cervix posteriorly in the pelvis over the levator plate of the pelvic diaphragm. The cardinal ligament lies at the lower edge of the broad ligament, between the peritoneal leaves, begin- ning just caudal to the uterine artery. The cardinal ligaments attach to the cervix below the isthmus and fan out to attach to the pelvic walls over the pirifor- mis muscle in the area of the greater sciatic foramen. Although when placed under tension they feel like lig- amentous bands, they are composed simply of perivas- cular connective tissue and nerves that surround the uterine and vaginal arteries and veins. Nevertheless, these structures have considerable strength. They provide support not only to the cervix and uterus but also to the upper portion of the vagina (paracolpium) to keep these structures positioned posteriorly over the levator plate of the pelvic diaphragm and away from the urogenital hiatus. During radical pelvic surgery, the cardinal ligaments provide a surgical boundary between the anterior paravesical space and the poste- rior pararectal space. Vaginal Connective Tissue Attachments and Extraperitoneal Surgical Spaces The attachments of the vagina to the pelvic walls are important in maintaining the pelvic organs in their nor- mal positions. Failure of these attachments, along with damage to the levator ani muscles, can result in various degrees of pelvic organ prolapse. The layer that is dissected during anterior or pos- terior colporrhaphy is often referred to as the vaginal fascia . The term fascia has many meanings; in this case, the vaginal “fascia” is the muscularis of the vagina. Multiple histologic studies over the past 100 years have failed to show a true fascial layer between the bladder and vagina or vagina and rectum. Histologically, this

PS = pubic

PS

symphysis

B = bladder V = vagina R = rectum

I

B

Retropubic or prevesical space

Vesicovaginal space

Cardinal ligament

V

Rectovaginal space

Pararectal space

R

Retrorectal or presacral space

The term ligament is most familiar when it describes a dense connective tissue band that links two bones, but it also describes ridges in the peritoneum or thickenings of the endopelvic fascia. The ligaments of the genital tract are diverse. Although they share a common desig- nation (i.e., ligament), they are composed of many types of tissue and have many different functions. Uterine Ligaments The broad ligament comprises peritoneal folds that extend laterally from the uterus and cover the adnexal structures. They have no supportive function and were discussed in the section on the pelvic viscera. At the base of the broad ligament, beginning just caudal to the uterine arteries, there is a thickening in the endopelvic fascia that attaches the cervix and upper vagina to the pelvic side walls ( FIG. 1.28 ), consisting of the cardinal and uterosacral ligaments (parametrium and paracervix). Use of the term ligament has caused confusion over the years because it implies a separate structure that connects two bony structures. In fact, they are mesenteries that transmit vessels and nerves from the pelvic walls to the genital tract. The term uterosacral ligament refers to that portion of this tissue that forms the medial and posterior mar- gin of the parametrium and that borders the rectouter- ine pouch (cul-de-sac of Douglas). The term cardinal ligament is used to refer to that portion that attaches the lateral margins of the cervix and vagina to the pel- vic walls. The course of the ureter as it forms a tunnel between the cardinal and uterosacral ligament forms a FIGURE 1.27  Schematic cross section of the pelvis showing cleavage planes and spaces including the retropubic (prevesi- cal), vesicovaginal, pararectal, rectovaginal, and retrorectal spaces.

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