Pubovesical ligament: A separate structure from the urethral supports (“pubo-urethral ligaments”)

Abstract

The position and mobility of the vesical neck influences not only continence but also the initiation of micturition. During an examination of urethral topography, there appeared to be two structures running from the region around the vesical neck to the pelvic walls which might influence vesical neck function. These structures, the urethral supports (“pubo-urethral ligaments”) and pubovesical ligaments, have previously been considered to be synonymous terms for a single structure. To investigate this disparity, 1,500 serial histologic sections from eight normal cadavers were examined, 28 cadavers were dissected, and whole pelvis cross sections from an embalmed cadaver were studied. Our observations indicate that there are two structures which run from the region around the proximal urethra and vesical neck to attach to the pelvic walls. The pubovesical ligaments are an extension of the detrusor muscle and its adventitia. They attach to the pubic bone and arcus tendineus fasciae pelvis. Their structure suggests that they contract to assist in vesical neck opening but would be poorly suited to provide support for the proximal urethra. The other structures represent the urethral supports (“pubo-urethral ligaments”) which connect the vagina and periurethral tissues to the muscles of the pelvic diaphragm and to the pelvic fasciae. Their structure appears to be adequate to explain urethral support. There are, therefore, two structures running from the tissues around the vesical neck to the pelvic walls. The structure of the pubovesical ligament suggests that it could assist in vesical neck opening, and the urethral supports could determine urethral position.