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