L18. GA - Anatomy of the Pelvic Cavity

The bony structure that forms the front wall of the pelvic cavity. Includes the pubic bone and the pubic symphysis.

Muscles that contribute to the floor of the pelvic cavity, forming the anterior portion of the pelvic floor. These muscles are essential for supporting organs and controlling defecation.

The iliac bone, ischium, and obturator internus muscles, form the lateral walls of the pelvic cavity. These muscles contribute to both support and movement in the pelvis.

The muscles, ligaments and bones that make up the posterior wall of the pelvic cavity include the sacrum, coccyx, sacroiliac joint, sacrotuberous ligament, and sacrospinous ligament. These are also involved in supporting the pelvic organs.

The muscles that contribute to the posterior pelvic floor. These muscles are essential for proper pelvic support and organ positioning.

The obturator artery and nerve, along with other branches of the internal iliac artery, reside medial to the obturator internus muscle. They play a vital role in supplying blood and nerve function to the pelvic structures.

The sacral plexus, autonomic plexuses, and branches of the internal iliac artery reside medial to the piriformis muscle. This area is vital for nerve and blood supply to the pelvis and lower extremities.

The uterine artery courses within the broad ligament towards the cervix. It ascends lateral to the uterus and connects with the ovarian artery near the uterine tube.

The vaginal artery is typically a branch of the uterine artery, but can also be a separate branch of the anterior trunk. It supplies blood to the vagina, bladder and rectum, serving a similar role to the inferior vesical artery in males.

Interconnected groups of veins form plexuses on the surface of pelvic organs, allowing for potential spread of infection or cancer.

The internal iliac vein receives drainage from the pelvic venous plexuses and connects to the inferior vena cava.

An anastomosis between the middle/inferior rectal veins and the superior rectal vein provides a connection between the systemic and portal circulations.

Lymphatic drainage from the pelvis and perineum ultimately flows to the aortic nodes. However, inferior structures near the external surface drain into the inguinal nodes first.

The sacral plexus, formed by nerves from the lumbar and sacral region, is located medial to the piriformis muscle and innervates the pelvis and lower limb.

The coccygeal plexus, a small network of nerves derived from the sacral and coccygeal region, innervates the skin of the anal triangle.

The obturator nerve, though not part of the sacral plexus, passes through the pelvis and ultimately innervates the medial thigh.

The internal iliac artery, located medial to the piriformis muscle, branches to supply various pelvic structures.

The internal iliac artery gives off branches to supply different structures in the pelvis. These branches are grouped into anterior and posterior trunks, and they further divide into smaller arteries.

The umbilical artery is a remnant of fetal development. It originally carried blood from the fetus to the placenta. In adults, it is a small, vestigial structure.

The superior vesical artery is responsible for supplying blood to the upper part of the urinary bladder and the distal part of the ureter. It usually arises from the umbilical artery.

The inferior vesical artery provides blood to the lower part of the bladder, the seminal vesicles (in males), and the prostate gland. It is a key artery for the male reproductive system.

The middle rectal artery supplies blood to the rectum, connecting with vessels from the superior and inferior rectal arteries. This creates a network for continuous blood flow to the rectum.

The obturator artery travels with the obturator nerve to the medial thigh providing blood supply to the leg. It often arises from the external iliac artery.

The internal pudendal artery exits the pelvis through the sciatic foramen and travels through the perineum, supplying blood to the pelvic floor and external genitalia.

The inferior gluteal artery, also exiting through the sciatic foramen, supplies the gluteal region and the hip joint, essential for movement.

The gonadal arteries provide blood to the reproductive organs. The ovarian artery travels with the suspensory ligament of the ovary, while the testicular artery enters the inguinal canal.

Supports pelvic organs and forms part of the pelvic floor; it's continuous with the pelvic walls where they meet the organs.

The connective tissue that forms a 'roof' over the pelvic diaphragm, helping to support the organs, and guides nerves and blood vessels.

An important passage for nerves and blood vessels in the ischioanal fossa, derived from the obturator fascia.

Keeps pelvic organs properly positioned and anchored to the pelvic walls, often carrying neurovascular bundles.

Forms pouches between pelvic organs, helping to compartmentalize the space and support organ positioning.

The largest nerve in the body, formed by the merging of the L4-S3 spinal nerves. It innervates the posterior thigh, and the entire leg and foot, which are essential for movement and sensation.

It is a nerve that provides sensory innervation to the skin over the posterior thigh and leg.

This nerve is responsible for motor control of the gluteus medius and minimus muscles, as well as the tensor fascia lata. They help with hip abduction (moving the leg away from the body) and external rotation.

This nerve innervates the gluteus maximus muscle. This muscle is crucial for hip extension (straightening the leg) and external rotation.

It is a nerve responsible for sensory innervation to the perineum, penis and clitoris and motor control over the external urethral and anal sphincters, and the levator ani muscle. These muscles are vital for bladder and bowel control, as well as sexual function.

These nerves are a part of the parasympathetic nervous system, which helps regulate bodily functions like digestion and bladder control in the pelvis. They originate from the sacral spinal cord between S2 and S4.

The sympathetic nervous system is crucial for 'fight or flight' responses. This system is responsible for regulating blood flow and other physiological processes.

They are a series of nerves that connect the sympathetic chain to the pelvic organs. It delivers signals to the pelvic viscera and external genitalia via the inferior hypogastric plexus?

The pelvic nerves are primarily responsible for the voluntary control of bowel and bladder function. They also regulate the sexual organs while the hypogastric plexus can modulate the activity of the pelvic viscera, making it a key player in visceral functions

These nerves are responsible for 'rest and digest' functions, like digestion and urination. They are located within the pelvic cavity, extending up to the splenic flexure of the large intestine.