Did you know the PELVIS has a diaphragm? 🤯

Muscles of the pelvic floor support viscera like the rectum, bladder, and reproductive organs. Openings of pelvic organs pass through hiatuses in this pelvic diaphragm.

#anatomy #pelvis

More below 👇

The PELVIC DIAPHRAGM is composed of several smaller muscles that can get tricky to keep straight (PRO TIP: know your pelvic osteology first!).

Here are some formulas to keep these muscles organized, working our way down from the whole diaphragm to its various constituent parts, then back again:

PELVIC DIAPHRAGM = LEVATOR ANI + COCCYGEUS

The coccygeus m. runs from the lower sacral vertebrae to the ischial spine - it is the most posterior of the pelvic diaphragm muscles. ✔️ that one off the list.

And, the levator ani m. has multiple sections:

LEVATOR ANI = PUBOCOCCYGEUS + ILIOCOCCYGEUS

Pubo- and ilio- coccygeus mm., commonly just called the levator ani m., form the core part of the pelvic diaphragm. They run from their respective pelvic bones to the tendinous arch of the levator ani m. on the sides of the pelvic bowl. 💓

I turned this into a mnemonic: LIP, meaning Levator ani m. is composed of the Ilio- and Pubo- coccygeus mm.

❗️ but wait, there's more, because now pubococcygeus has parts, depending on sex:

PUBOCOCCYGEUS = PUBORECTALIS + (PUBOVAGINALIS *or* PUBOPROSTATICUS)

Puborectalis forms a sling around the rectum. The other two are sex-specific and support viscera of their same name.

Just to be clear, this is still all part of LEVATOR ANI m., which is the biggest component of the whole PELVIC DIAPHRAM! Whew! We did it! 🤓

The pelvic diaphragm is nearly always "on" - keeping our insides, well, IN! The movement and relaxation that accompanies each breath keeps these muscles in good shape - supportive, but not overly tight and restrictive on the organs that pass through them.