Lab 11: The Pelvis Flashcards
pelvis
- 2 os coxae
- coccyx
- sacrum
- iliac crest
- ischial spine
- ischial tuberosity
- ischial tuberosity- sit on it
- subpubic angle- broad and wide -> female
- subpubic angle- narrow and tall -> male
- arcuate line or pelvic brim- divides the true pelvis from the false pelvis
- false pelvis is above arcuate line
- true pelvis is below the arcuate line
- greater sciatic notch is bigger in females
pelvic brim
- posteriorly- sacral plateau
- anterior- pectin pubis
- lateral- arcuate line
pelvis ligaments
- anterior sacroiliac joint- stabilized anteriorly and posteriorly -> anterior and posterior sacroiliac ligament
- inguinal ligament- thickened lower margin of the external oblique muscle
- running from the anterior iliac spine to the pubic tubercle
pelvis ligaments
- greater and lesser sciatic notch
- ligaments enclose and form a foramen
- greater sciatic foramen
- lesser sciatic foramen -> goes to perineum
- sacrospinous ligament- from sacrum to ischial spine
- sacral tuberous ligament- from the sacrum to the ischial tuberosity
pelvic cavity
- continuous with abdominal cavity
- peritoneum extends into the false pelvis
- small/large intestine sits in false pelvis and are covered in peritoneum
- pelvic cavity begins at pelvic brim
- organs in true pelvis are retroperitoneal
- bounded inferiorly by pelvic diaphragm -> muscular floor
pelvic diaphragm
- separates the pelvic cavity from the perineum
- runs from the pubic bone to the coccyx
- urethra, anal canal pass through the pelvic diaphragm
- urogenital hiatus- allow passage of the urethra in both sexes -> vagina in females
- muscular components:
- levator ani
- coccygeus
- innervation- S2-S4 ventral rami
levator ani
- three muscles:
- pubococcygeus
- puborectalis
- iliococcygeus
perineum
- region of the pelvis below the pelvic diaphragm
- made of 2 triangles:
1. urogenital triangle (anterior)- perineal membrane divides superior portion and inferior portion
2. anal triangle (posterior)
muscles of the urogenital triangle
- above the perineal membrane:
- sphincter urethrae
- deep transverse perineus
- inferior to perineal membrane:
- ischiocavernous- covers the crus of the penis or clitoris (sides of triangle)
- bulbospongiosus- covers bulb of penis and the bulb of the vestibule (middle of triangle)
- superficial transverse perineus (base of triangle)
muscles of the anal triangle
-external anal sphincter
erectile tissue
-found deep to the inferior compartment muscles (bulbospongiosus and ischiocavernosus)
perineal erectile tissues: female
- ischiocavernosus covers crus of clitoris and corpus cavernosum
- bulbospongiosus covers bulb of vestibule
perineal erectile tissues: males
- ischiocavernosus covers crus of penis and crus of clitoris and corpus cavernosum
- bulbospongiosus covers bulb of penis and corpus spongiosum
- two columns of corpus cavernosum and one corpus spongiosum
- ischiocavernosus covers crus cavernosum and bulbospongiosus covers bulb and sponge tissue
corpus cavernosum
-homologous to crus of penis
bulb of the vestibule and penis
-corpus spongiosum
innervation of erectile tissues
- erection- parasympathetics to corpus cavernosum
- ejaculation- sympathetics to bulbospongiosus muscle
male perineal tissues
- bulb of penis and corpus spongiosum transmit the urethra
- paired corpus cavernosum
- corpus spongiosum and urethra running through it
- deep artery of the penis supplies the corpus cavernosum
bladder
- receives urine from the ureters
- detrusor muscle (smooth and thick) -> contracts when we pee
- orifices of the uteters
- smooth portions of the bladder- trigone
- sphincter urethrae- somatic, outside pelvis (perineum)
- urethra is short for females and long for males
urethra: males
- extends down from prostate- prostatic urethra
- membranous urethra
- spongy/penile urethra- through shaft of penis
prostate
-contributes to the ejaculatory fluid
bulbourethral glands
- outside pelvis
- perineum
- secrete fluid
- homologous to vestibular gland
- produce fluid that contributes to ejaculation
- whole purpose is to neutralize acidity of vagina
- embedded in the internal sphincter urethrae
greater vestibular gland
- during sexual aurosal- lubrication
- fluid for lubrication is highly acidic
uterus
- fundus
- body
- cervix- protrudes into the vaginal cavity -> part of the uterus still though
- covered in peritoneum
- 3 layers:
- endometrium
- myometrium
- perimetrium
broad ligament
- double layer peritoneum
- 3 portions:
- mesovarium- attached to the ovary and bread ligament of uterus
- mesosalpinx- portion that attached to fallopian tube
- mesometrium- everything else
round ligament
- adhere to abdominal wall
- connects ovary and abdominal wall
suspensory ligament of the ovary
- where the gonadal arteries travel
- connects uterus and pelvic wall
fallopian tube
-isthmus, infundibulum with fimbriae, and ampulla
ovarian ligament
- leads to ovary
- connects ovary and uterus
ductus defernes
- gets stuck under the peritoneum between the bladder
- ampulla- widen portion
seminal vesicle
-adds fluid to ejaculation
path of ejaculation
-scrotum -> testis -> epididymis -> ductus defernes -> seminal vesicles -> ejaculatory duct -> prostate gland -> bulbourethral gland -> urethra -> penis `
testes
- covered in tunica albuginea and tunica vaginalis (makes sperm)
- testicular artery
- pampiniform plexus of veins (thermoregulation)
deep inguinal ring
- opening in the internal oblique muscle
- where the testes descend
- through inguinal canal
- come out at the external oblique at the superficial inguinal ring
spermatic cord
- lateral abdominal walls
- fascial layers:
- external spermatic fascia- from external abdominal oblique aponeurosis
- cremaster muscle and fascia- from internal abdominal oblique
- internal spermatic fascia- from transversalis fascia
- transversus abdominis is not involved!
aorta
- splits into the left and right common iliac arteries
- common iliac arteries split into the internal and external iliac arteries
arterial supply from abdominal aorta
-ovarian artery and testicular artery -> gonadal arteries
arterial supply from the inferior mesenteric artery
-superior rectal artery -> rectum
arterial supply from the external iliac artery
-inferior epigastric artery -> small branch to cremaster muscle (surrounds the testes)
arterial supply from the internal iliac
- branches into anterior division and posterior division
- anterior division- obturator artery -> exits through obturator foramen
- inferior gluteal artery -> exits through greater sciatic foramen -> gluteal
- umbilical artery -> gives off superior vesical artery to bladder, then becomes umbilical ligament
- middle rectal artery -> rectum
- internal pudendal artery -> exits through greater sciatic foramen -> into perineum through lesser sciatic foramen, then gives off: perineal artery, inferior rectal artery, and artery of penis/clitoris
- inferior vesical artery (males only)- prostate, seminal vesicles, ductus deferens OR uterine artery (females only) -> uterus
- posterior division:
- lateral sacral artery
- superior gluteal -> exits through greater sciatic foramen -> gluteal muscles
internal pudendal artery
-gives off deep artery, dorsal artery, and bulbo
parasympathetic innervation in the pelvis originates from the
-pelvic splanchnic nerves
sperm is produced in the
seminiferous tubules
innervation of bulbospongiosus and ischiocavernosus
-perineal nerve
Bony Pelvis
- left and right os coxae, sacrum, coccyx
- os coxae- composed of 3 fused elements: ilium, ischium, pubis
- pubic bones articulate with one another anteriorly by symphysis (fibrocartilaginous)
- posteriorly the ilium articulates with the ala of the sacrum at the auricular surface -> forms sacroiliac joint
- os coxae is waisted below the auricular surface by the greater sciatic notch -> delimited inferiorly by the ischial spine
- below the spine, ischium is indented by the lesser sciatic notch -> bounded inferiorly by the ischial tuberosity
- ischial pubic bodies are joined by the superior ramus of the pubis superiorly and the ischiopubic ramus inferiorly
- these rami are surrounded by obturator foramen
- upper margin of the superior ramus of the pubis has a sharp crest that continues posteriorly as a ridge -> arcuate line
- crest and arcuate line constitute the pelvic brim -> separate the false pelvis and pelvic cavity (true pelvis or obstetrical pelvis)
pelvic ligaments
- ilium and sacrum are joined anteriorly along the edge of the auricular surface by the anterior sacroiliac ligament and posteriorly by the posterior sacroiliac ligament
- ischial spine and sacrum are connected by the sacrospinous ligament -> closes the open end of the greater sciatic notch -> creating greater sciatic foramen
- ischial tuberosity and sacrum are connected by the sacrotuberous ligament -> with the sacrospinous ligament they close the open end of the lesser sciatic notch -> create the lesser sciatic foramen