Diaphragma Urogenitale

Abstract

For many years, the radical prostatectomy has been an established method for treating prostatic cancer in the clinical stage T1–T2. In terms of operative technique, although both suprapubic and perineal access are possible, the latter having a number of advantages. Both sphincters of the neck of bladder, the vesical sphincter and the urethral sphincter, can easily be prepared and anastomosed. During preparation, it becomes apparent that in the area of the urethral sphincter there is no continuous transversal muscle plate which could correspond to the diaphragma urogenitale (urogenital diaphragm). This is even more surprising as this structure has been described in well-known anatomical textbooks (Pernkopf 1994) and urological surgery manuals (Marshall 1991; Glenn 1992) as a prominent structure in the small pelvis. Apparently, fascie and transversal muscle fibres are supposed to strengthen the pelvic floor between the lower branches of the pubic bone, keep the urethra (and in the female the vagina, too) in the median line in both sexes. This muscle plate enclosed by fascie is called the diaphragma urogenitale, the main element of which has been defined as the musculus transversus perinei profundus (deep transverse perinei muscle; Alverdes 1959; Brooks et al. 1998).

“All these distinctions go either too far or not far enough. If the muscle mass filling a certain space were to be separated further, the number of muscle cords deserving a special term could be easily increased. The first thing to do is to find a name for the whole, more or less complicated muscular plate from the front point of the pelvic aperture, and I choose the oldest name, which has the advantage of suiting both sexes and which does not prejudge anything by virtue of its physiological name.” Henle (1866)