Levator ani muscle

The levator ani (aka , also known as the muscularpelvic diaphragm) is, is the musculotendinous sheet that forms the majority of the pelvic floor, supports the pelvic viscera, and aids in urinary and fecal evacuation as well as maintaining continence.

ItThe levator ani has 3three main components, each of which is paired^1,2,5:

• pubococcygeal (pubovisceral) muscle
  • subparts: the ischiococcygeus (akapuboperineal, pubovaginal, puboanal
• iliococcygeus muscle
• puborectalis muscle

The coccygeus), the iliococcygeus, and muscle is sometimes included ³.

The pubococcygeus. Each pair of muscles fuses in the midline to form a raphe which extends runs from the coccyx posteriorly and splits anteriorly around the ano-urogenital hiatus, each sling attaching to the inner aspect of the bodysurface of the pubis.  In reality, it is difficult to seperate these muscles from one another, as portions and obturator fascia with fibres fusing medially at the perineal body and musculature of their fibers are interlacedthe prostate/vagina. They also perform similar functions.

The ischiococcygeus is a triangular muscle with it'sits base attaching attaching to the lateral lateral aspect of the inferior sacrum and coccyx and apex attached to the ischial spine. It forms the postero-superiorposterosuperior part of the levator ani. It flexes the coccyx anteriorly and partially fuses with the sacrospinous ligament. It's innervated by the inferior sacral segments (S4 and S5) directly through the sacral plexus and is supplied by the inferior gluteal artery. It is absent in some people.

The The iliococcygeus attaches the inner tip of the coccyx posteriorly. Posterolaterally, it attaches to the ischial spine and along the tendinous arch of the obturator fascia (aka(a.k.a. the tendinous arch of the levator ani), which is a thickened band of the fascia covering the inner aspect of the obturator internus muscle. AnteriolyAnteriorly and medially, it fuses with the pubococcygeus.