Suspensory axis is key to pelvic reconstruction.(Gynecology)

ST. LOUIS -- Recognition of the importance of the suspensory axis of the vagina is necessary for a successful pelvic support surgery, according to Carl W. Zimmerman, M.D.

If disruptions of this axis around the pericervical ring are corrected surgically, the mechanical function of suspension can be reestablished, said Dr. Zimmerman, professor of obstetrics and gynecology at Vanderbilt University, Nashville, Tenn. He outlined the restoration of the vaginal suspensory axis, what he called the "most important concept in pelvic reconstructive surgery," at the 14th International Pelvic Reconstructive and Vaginal Surgery Conference.

The vaginal suspensory axis is a continuum of connective tissue that serves as the primary structure to hold the central pelvic organs above the levator plate and behind the urogenital hiatus. The named components of this axis are the perineum, rectovaginal septum, pericervical ring, uterosacral ligaments, and presacral periosteum. The elements involved with holding the bladder, uterus, rectum, and vagina above the pelvic diaphragm are located within the posterior vagina.

"When these structures are anatomically intact, prolapse does not occur. When they are disrupted, one or more of the central pelvic organs have a tendency to fall through the pelvic floor and to create prolapse," Dr. Zimmerman said at the conference, which was sponsored by the Society of Pelvic Reconstructive Surgeons and Emory University.

"The mechanical function of suspension should be contrasted with support. Support of the pelvic floor is provided by the muscles of the pelvic diaphragm and their associated parietal fasciae," he said.

Analysis of the mechanics of childbirth can provide information to deduce the most likely location of damage during labor. "The narrowest diameter in the pelvis is between the ischial spines. This plane is intersected by all named components of the endopelvic fascia. The passage of a baby's head through the diameter subjects this area to high and sustained pressures during childbirth," he said.

In addition, the pericervical ring is substantially stressed by dilation of the cervix. The cardinal movements of internal rotation, flexion, and descent are required to allow the baby to negotiate this area of the pelvis. Maximum pelvic connective tissue strength is located within the most restricted ...