The superior fold or ligament extends from the summit of the bladder to the posterior surface of the recti muscles, and is partially reflected over the remains of the urachus and hypogastric arteries. This fold rather consists of three folds which diverge below and con verge towards the umbilicus; they present a falciform appearance towards the abdomen, particularly when the bladder is contracted. In the foetus these superior folds, particularly the lateral, are very distinct, as they each con tain the umbilical artery. The urachus, which is in the centre, is also at that age very distinct though shorter; its vesical end is often pervious for about an inch : it is always closed before it arrives at the umbilicus, it then becomes fila mentous, and is soon lost on the umbilical arteries.
The second medium of connexion between the bladder and the parietes of the pelvis is the vesical fascia, the reflections of which con stitute the true ligaments of the bladder. The vesical is the internal lamina of the pelvic fascia reflected from the latter at the upper border of the levatores ani muscles : it covers the internal surface of this muscle on each side, and descends as low as a line drawn from the inferior border of the symphysis pubis to the spinous processes of the ischia., On this level it is reflected on the prostate gland and on the sides of the bladder, and posterior to this organ on the rectum and on several of the pelvic vessels and nerves. The anterior or vesical portion of this fascia is distinct and strong, and forms a pouch on each side of the bladder which assists in closing the pelvis; posteriorly this fascia is thin and cellular, being perforated by several vessels. Its anterior reflections constitute the true anterior liga ments of the bladder, which are described as arising from the lower margin of the pubis on either side of the symphysis, then passing back wards and upwards on the upper surface of the prostate gland, and expanding on the an terior region of the bladder; many of their fibres become continuous with the muscular fibres of the bladder. A depression exists between these two ligaments, along which the dorsal veins the penis run from beneath the arch of the pubis to the side of the bladder in their course to the internal iliac veins, in which they terminate. The fascia, however, is not deficient in this depression between these ligaments, but is continued from one to the other so as to line this hollow and to cover the upper surface of these veins. The anterior ligaments present a smooth concavity towards the abdomen or pelvis; .their perineal or infe rior aspect is convex, and has inserted into it the posterior lamina of the inter-osseous or triangular ligament of the urethra.
The true lateral ligaments of the bladder are also two in number, one on each side ; each is continuous with the anterior, and is formed by the reflection of the vesical fascia from the internal surface of the levator ani muscle to the side of the prostate gland, and of the bladder immediately above and outside the vesiculm seminales. The pelvic and vesical
fasciae will be more particularly noticed in the article PELVIS.
Lastly, the bladder is retained in situ by the attachments of the cervix; these take place not only directly by the ligaments which have been just described, but also indirectly through its connexion to the urethra and of the latter to the pubes through the medium of the trian gular ligament of the urethra. This ligament, for a fuller description of which we refer to the article PERINEUM, is a strong aponeurosis intimately connected to the rami of the pubes and ischia, and there continuous with the obtu rator fascia of each side. It is strong, tense, and unyielding, and closes all the anterior portion of the inferior orifice of the pelvis; it is perforated by a small opening, through which the urethra passes about an inch inferior to the bony edge of the pubes; the edges of this opening are continued on the urethra both to wards the perineum and towards the pelvis. The process which extends in the former or inferior direction is lost on the bulb of the urethra, while that which extends in the pos terior or superior direction, and which is more distinct and strong, encompasses the mem branous part of the urethra, (which, while in situ, is very short,) and is then inserted or becomes continued into that reflected portion of the vesical fascia which forms the true anterior and lateral ligaments of the bladder ; thus the commencement of the urethra, the prostate gland, and the neck of the bladder, which must be nearly synonymous with the prostatic portion of the urethra, are all retained in a nearly fixed position, and the continuity of the different aponoreuses in this region serves to afford mutual strength and general security.
The bladder, notwithstanding the foregoing connexions, is subject to displacement. In the male this occurrence seldom happens, although in some cases of very large inguinal or scrotal herniae this viscus has been gradually drawn into the sac, in consequence, most probably, of adhesion between it and the omentum or some other of the protruded parts. We have already mentioned how a portion of the lining membrane may become protruded between the muscular fasciculi and form a sac which may increase to a considerable size, and extend into some new and even remote situation. In the female the bladder is very liable to partial pressure as well as to displacement, owing to different conditions of the uterus, such as retroversion, inversion, and prolapses.