Anatomy Flashcards
What are the boundaries of the pelvic inlet?
Anterior: pubic crest (pubic symphysis)
Posterior: ala or base of sacrum and sacrovertebral angle or sacral promontory
Laterally: Iliopectineal line
What are the boundaries of the pelvic outlet?
Anterior: pubic arch (under side of pubic crest)
Posterior: tip of coccyx
Laterally: ischial tuberosities
Posteriolaterally: inferior margin of sacrotuberous ligament
Three spaces of the pelvis:
- ) Greater/false pelvis
- ) Lesser/true pelvis
- ) Pelvic floor diaphragm
What does the pelvic diaphragm consist of?
Two layers of fascia with levator ani and coccygeus in between the layers
Three parts of levator ani from medial to lateral:
Puborectalis
Pubococcygeus
Coccygeus/Iliococcygeus
What is the anococcygeal raphe/body?
The meeting of the two pubococcygeus muscles
What forms the vesicouterine pouch?
Parietal peritoneum from the posterior roof of the bladder reflecting back onto the anterior aspect of the uterus at the isthmus of the uterus
What forms Douglas pouch (rectouterine pouch)?
Peritoneum passing over the fundus of uterus and descending the entire aspect o the uterus onto the posterior vaginal wall before reflecting superiorly onto the anterior wall of the inferior rectum
What is the pararectal fossae?
Deep pouches on each side of the rectum
What is the broad ligament of the uterus?
Double peritoneal fold that extends between the uterus and lateral pelvic wall on each side
In males what is the rectovesical pouch?
Peritoneum reflects superiorly of the bladder and onto the anterior surface of the inferior rectum
What is the hypogastric sheath?
Between retropubic space and presacral space (around rectum)
From lateral to medial what are the three portions of the hypogastric sheath?
- ) Lateral ligament of bladder
- ) Cardinal ligament in female; rectovesical septum in males
- ) Lateral rectal ligament
What is the ischioanal fossae?
Two wedge-shaped spaces filled with fat and connective tissue on either side of the anus
Ischioanal fossae boundaries:
Anterior: Bodies of pubic bones
Posterior: Sacrotuberous ligament and gluteus maximus
Medial: External anal sphincter
Lateral: Ischium and overlapping inferior part of obturator fascia
What is the anterior recesses of the ischioanal fossae?
Anterior parts of the fossae that extend into the urogenital triangle superior to the perineal membrane
What is the pectinate line?
Space where the hindgut endoderm meets with the ectoderm
What does the pectinate line divide?
Upper 2/3 of anal canal from lower 1/3 of the anal canal
What innervates the upper 2/3 of pectinate line?
Inferior hypogastric plexus (visceral innervation)
What innervates the lower 1/3 of pectinate line?
Inferior rectal nerve (somatic innervation)
What does the inferior rectal nerve branch from?
Pudendal nerve
What is the blood supply to upper 2/3 of pectinate line?
Superior rectal artery branch from IMA
What is the blood supply to lower 1/3 of pectinate line?
Inferior rectal artery branch from internal pudendal artery
What are anal columns and what do they denote?
Longitudinal ridges in the anal canal; the superior ends of the anal columns is the anorectal junction
What joins the inferior portion of the anal columns?
Anal valves
What are found just superior to anal valves in between anal columns?
Anal sinuses
What is the posterior margin of the perineal membrane and perineal body?
Superficial (Colles’) perineal fascia
In males what does Colles’ perineal fascia continue with?
Superficial (dartos) fascia
What does Colles’ fascia continue with superiorly?
Scarpa’s fascia of the abdomen
What does the deep perineal fascia invest in?
Ischiocavernosus
Bulbospongiosus
Superficial transverse perineal muscles
Borders of the superficial pouch in males?
Superior: perineal membrane
Inferior: Superficial (Colles’) perineal fascia
Muscles of the superficial pouch?
Superficial transverse perineal muscle
Ischiocavernosus
Bulbospongiosus
Three cylindrical cavernous bodies of erectile tissue?
Paired corpora cavernosa (dorsally)
Single corpus spongiosum (ventrally)
What is the deep fascia of the penis (Buck’s fascia)?
Continuation of deep perineal fascia that forms a strong membranous covering for the three erectile tissue
What forms the crura of the penis?
Posteriorly where the corpora cavernosa are separate
What forms the glans penis?
Corpus spongiosum expanding at the tip containing the urethral orifice
Boundaries of the deep pouch in males?
Inferior: Perineal membrane
Superior: pelvic diaphragm
Main arterial supply to the penis?
Internal pudendal arteries (branches)
Where do the dorsal arteries of the penis run?
On each side of the deep dorsal vein in the dorsal groove between corpora cavernosa
Where do the deep arteries of the penis run?
They pierce the crura proximally and run distally in the center of the corpora cavernosa
Where is the deep dorsal vein of the penis?
In the deep fascia (Buck’s) directly on top of the corpora spongiosum
Where are the superficial dorsal veins?
On top of the deep fascia (Buck’s); drains skin and subcutaneous tissue
Muscles of the deep pouch?
External urethral sphincter
Deep transverse perineal muscle
What is contained in female perineal pouch?
Vestibular bulbs
Crura of clitoris
Greater vestibular (Bartholin’s) glands
What are the vestibular bulbs?
Paired elongated erectile tissue along the sides of the vaginal orifice
What is the vestibule of the vagina?
Space surrounded by labia minora
What does the female deep pouch contain?
External urethral sphincter
Urethra
Female bounds of deep perineal pouch?
Inferior: perineal membrane
Superior: pelvic diaphragm
