The pelvic fasciae are the fascia of the pelvis and can be divided into: * (a) the fascial sheaths of ** the

Obturator internus The internal obturator muscle or obturator internus muscle originates on the medial surface of the obturator membrane, the ischium near the membrane, and the rim of the pubis. It exits the pelvic cavity through the lesser sciatic foramen. The i ...

muscle ( Fascia of the Obturator internus) ** the

Piriformis The piriformis muscle () is a flat, pyramidally-shaped muscle in the gluteal region of the lower limbs. It is one of the six muscles in the lateral rotator group. The piriformis muscle has its origin upon the front surface of the sacrum, and in ...

muscle ( Fascia of the Piriformis) ** the

pelvic floor The pelvic floor or pelvic diaphragm is composed of muscle fibers of the levator ani, the coccygeus muscle, and associated connective tissue which span the area underneath the pelvis. The pelvic diaphragm is a muscular partition formed by the lev ...

* (b) fascia associated with the organs of the pelvis.

Structure

Fascia of pelvic organs

Pelvic fascia extends to cover the organs within the pelvis. It is attached to the fascia that runs along the pelvic floor along the tendinous arch. The fascia which covers pelvic organs can be divided according to the organs that are covered: * The front is known as the "vesical layer". It forms the anterior and lateral ligaments of the

bladder The urinary bladder, or simply bladder, is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine enters ...

. * In males, its middle lamina crosses the floor of the pelvis between the rectum and vesiculæ seminales as the ''rectovesical septum''; in the female this is perforated by the cervix and is named the transverse cervical ligament. * At the back, the fascia passes to the side of the rectum; it forms a loose sheath for the rectum, but is firmly attached around the

anal canal The anal canal is the part that connects the rectum to the anus, located below the level of the pelvic diaphragm. It is located within the anal triangle of the perineum, between the right and left ischioanal fossa. As the final functional seg ...

. This portion is known as the "rectal layer".

Fascia of the pelvic floor

;Superior The part of the pelvic fascia on the pelvic floor covers both surfaces of the Levatores ani muscle. The layer covering the upper surface of the

pelvic diaphragm The pelvic floor or pelvic diaphragm is composed of muscle fibers of the levator ani, the coccygeus muscle, and associated connective tissue which span the area underneath the pelvis. The pelvic diaphragm is a muscular partition formed by the le ...

follows, above, the line of origin of the Levator ani and is therefore somewhat variable. In front it is attached to the back of the

pubic symphysis The pubic symphysis is a secondary cartilaginous joint between the left and right superior rami of the pubis of the hip bones. It is in front of and below the urinary bladder. In males, the suspensory ligament of the penis attaches to the pubi ...

about 2 cm above its lower border. It can then be traced laterally across the back of the superior ramus of the pubis for a distance of about 1.25 cm, when it reaches the

obturator fascia The obturator fascia, or fascia of the internal obturator muscle, covers the pelvic surface of that muscle and is attached around the margin of its origin. Above, it is loosely connected to the back part of the arcuate line, and here it is conti ...

. It is attached to this fascia along a line which pursues a somewhat irregular course to the spine of the ischium. The irregularity of this line is because the origin of the Levator ani, which in lower forms is from the

pelvic brim The pelvic brim is the edge of the pelvic inlet. It is an approximately Mickey Mouse head-shaped line passing through the prominence of the sacrum, the arcuate and pectineal lines, and the upper margin of the pubic symphysis. Structure The pel ...

, is in man lower down, on the obturator fascia. Tendinous fibers of origin of the muscle are therefore often found extending up toward, and in some cases reaching, the pelvic brim, and on these the fascia is carried. ;Inferior The diaphragmatic part of the pelvic fascia covers both surfaces of the Levatores ani. The inferior layer is known as the anal fascia. It is attached above to the

along the line of origin of the Levator ani, while below it is continuous with the superior fascia of the

urogenital diaphragm Older texts have asserted the existence of a urogenital diaphragm, also called the triangular ligament, which was described as a layer of the pelvis that separates the deep perineal sac from the upper pelvis, lying between the inferior fascia of ...

, and with the fascia on the Sphincter ani internus.

Additional images

File:Gray547.png, The relations of the femoral and abdominal inguinal rings, seen from within the abdomen. Right side.

References

External links

* {{Authority control Pelvis Fascia