Topographic formations of the pelvis

Topographic formations are spaces that are bounded by given anatomical structures and are important for locating other anatomical structures - typically nerves, arteries and veins. More information can be found on the pages of specific structures. In the pelvic area, we describe the following topographic formations:

Ischioanal fossa
It is located lateral to the rectum. Its contents are the corpus adiposum fossae ischioanalis and the below mentioned canalis pudendalis, or the pudendal canal of Alcock.

Pudendal canal
Also called Alcock's canal, it is located dorsal to the iliococcygeus muscle and on the medial side of the obturator internus muscle. A nerve runs through the channel, after which the topographical place is named - pudendal nerve. We also mention it in topographic formations of the lower limb.

Rectouterine pouch
Also called space of Douglas, found only in women. This is the deepest point of the peritoneal cavity when standing, so fluid and other pathological contents can accumulate here. The space is palpable during rectal examination.

Vesicouterine pouch
It is found only in women.

Rectovesical pouch
Also called Proust's space, it is only found in men. The deepest point of the peritoneal cavity in a man.

Urogenital triangle
Front triangle

Anal triangle
Back triangle

Trigone of the urinary bladder
Triangular field on the dorsal side of the urinary bladder. The border is formed by the junction between the mouths of the ureters and the urethra.

Spermatic cord
Although it is not a typical topographic formation, but rather a bundle of anatomical structures, we present it here as well.