Deep Pelvis Anatomy PDF

Functional Human Anatomy Deep Pelvis D R. D O N AL M U R R AY PH D C O N T R IBU T IO N S BY: D R. E LLE N C O S T E LLO, PT, P H D Session Objectives Identify the muscles of the Pelvic Diaphragm (Pelvic floor) Identify the muscles that make up the Levator Ani Identify the neurological structures t...

Functional Human Anatomy Deep Pelvis D R. D O N AL M U R R AY PH D C O N T R IBU T IO N S BY: D R. E LLE N C O S T E LLO, PT, P H D Session Objectives Identify the muscles of the Pelvic Diaphragm (Pelvic floor) Identify the muscles that make up the Levator Ani Identify the neurological structures that arise in the deep pelvis Revisit the vascular supply in the deep pelvis from an internal perspective PELVIC DIAPHRAGM Aka Pelvic floor Composed of 2 levator ani muscles and 2 (ischio) coccygeus muscles Supports abdominal viscera Separates the pelvic cavity from the perineum Penetrated by the rectum, urethra and vagina MUSCLES OF THE PELVIS Levator Ani muscle comprised of 3 muscles: 1. puborectalis 2. pubococcygues 3. iliococcygeus  Innervated by the perineal branches of the S3 and S4 ventral rami  Actions-supports pelvic viscera, resists the thrusts of increased intra-abdominal pressure (coughing, lifting heavy objects) Piriformis ms Piriformis ms.  In lab: palpate for the ischial spine on the lateral pelvic wall X Ischiococcygeus ms puborectalis Muscles cont. (Ischio) Coccygeus muscle forms pelvic diaphragm with levator ani muscles Innervation- branches of S4 and S5 ventral rami Actions-supports coccyx, pulls it anteriorly; assists levator ani muscles. x Piriformis ms NERVES OF THE PELVIS Lumbosacral plexus  Descending portion of L4 ventral ramus unites with L5 ventral ramus to form the lumbosacral trunk  Lumbosacral trunk passes ant. to ala of sacrum and joins the ventral rami of S1, S2, S3, S4 Branches of Lumbosacral Plexus Sciatic nerve-ventral rami L4-S3  tibial and common peroneal portions- supplies post. thigh muscles, lower leg (shank) and foot Pudendal nerve-ventral rami S2- S4  Exits grtr sciactic foramen; reenters through lssr sciatic foramen  Branches: inferior anal n; perineal n., dorsal n of the penis/clitoris (nice to know)  Supplies the external urethral sphincter, anal sphincter and partial supply of levator ani; sensation to external genitalia N. To Levator Ani ARTERIES OF THE PELVIS Int. Iliac Internal iliac a.- terminal branch of a the common iliac a. (external iliac is other terminal branch) Branches of internal iliac a. to identify: Iliolumbar a.- ascends laterally and supplies iliacus, psoas major, quadratus lumborum mm. Superior gluteal a.- largest branch; runs between the lumbosacral trunk (L4,5) and S1. Supplies piriformis, obt. internus, and gluteal mm. Lateral sacral a.-pass medially, ant. to sacral ventral rami giving off spinal branches through the sacral foramina ARTERIES of THE PELVIS CONT. Obturator a.-runs on lat wall of pelvis with obturator N. and V. through obturator foramen Inferior gluteal a.  largest branch of ant. trunk, supplies buttock and post thigh. Often runs between S1 & S2 (although Netter has it between S4 and S5 in this slide & S2, S3 in atlas) Internal pudendal a. (usually closer to the ischial spine than inferior gluteal a.)  Iliolumbar a. Sup gluteal a. Vesical aa. Rectal aa. Internal Pudendal a. closest to ischial spine vs. Inf Gluteal a. Summary What soft tissues create the levator ani musculature? How is it the same or different from the pelvic floor/diaphragm? What is the innervation of the levator ani and pelvic diaphragm? What is the function of the pelvic diaphragm? Can you identify the branches of the lumbosacral plexus? Can you trace the path of the abdominal aorta and identify its branches in the deep pelvis.