Pelvic nerve plexus trauma at radical hysterectomy and simple hysterectomy: the nerve content of the uterine supporting ligaments.

Abstract

A major cause of the pelvic morbidity after a radical hysterectomy (RH) is thought to be damage to the pelvic nerve plexus, but direct evidence is lacking. We set out to determine the nerve content of the uterosacral ligaments (USLs) and cardinal ligaments (CLs) at the level at which they are divided during a radical hysterectomy and a simple hysterectomy. Intraoperative cross-sectional biopsies were collected from the lateral third of the uterosacral ligaments (USLs) and cardinal ligaments (CLs) in 20 women undergoing radical hysterectomy (RH) and from the uterine insertion of these ligaments in 11 women undergoing a simple hysterectomy. Quantitative immunocytochemistry was utilized to demonstrate and quantify the nerve content of the uterine supporting ligaments at the level at which they are divided in a RH and in a simple hysterectomy. Indirect immunofluorescence staining of frozen cryostat sections was performed using primary antibodies to PGP 9.5 (a pan-neuronal marker). A computer-assisted image analyzer measured the percentage area of immunoreactivity (PAI) that was used to quantify the nerve density. Confocal microscopy was used to determine the composition and spatial arrangement of nerve fibers in the ligaments. The PAI was significantly greater in the RH biopsies than in the simple hysterectomy biopsies, for both the CLs (P < 0.001) and the USLs (P < 0.001). In the RH biopsies, more nerve tissue was present in the USL than CL (P = 0.01), and compared with the CL more of the nerve fibers in the USL were concentrated in large trunks. Excluding these trunks and autonomic ganglia, the free nerve content of the USL was lower than that of the CL (P < 0.001). The presence of nerve trunks, autonomic ganglia, and free nerve fibers within the lateral third of the USL and CL is consistent with extension of the inferior hypogastric plexus along these ligaments to the pelvic organs. The uterine supporting ligaments contain autonomic nerves and ganglia, as extensions of the inferior hypogastric plexus. The USLs have a greater nerve density than the CLs. Because RH disrupts more nerve tissue than a simple hysterectomy, these data provide further evidence for the neurogenic etiology of pelvic morbidity after RH.