Uterosacral Nerve Transection
Pain fibers emanating from the cervix and the lower portion of the uterine corpus traverse the uterosacral ligaments posteriorly to the sacrum and finally to the inferior hypogastric plexus (Fig. 39–1A, B). Section of these ligaments close to their origin at the junction of the upper vagina and the cervix has been advocated for the relief of dysmenorrhea. The operation does not relieve pain as completely as does presacral neurectomy. Nevertheless, uterosacral transection is a simpler operation to perform and usually is done via the laparoscopic approach.
The structures that must be identified to avoid injury are the right and left ureters and the uterine arteries. The latter are millimeters from the anterolateral aspect of the uterosacral ligaments. The former are within 1 to 2 cm of the ligaments (i.e., laterally located).
The uterosacral transection may be performed by laser ablation or by electrosurgical cutting. It is preferable to cut the ligament starting 1 to 2 mm from the lateral margin and to extend the cut medially toward the cul-de-sac (Fig. 39–2). The incision starts 4 to 5 mm distal from the locus where the ligament attaches to the uterus. The cut should be approximately 4 to 5 mm deep as well (Fig. 39–2, Inset). Some surgeons prefer to carry a 2-mm shallow incision across the posterior surface of the uterus, connecting the two severed uterosacral ligaments (Fig. 39–3).
