Female Internal Reproductive Organs Pt. 2/Perineal Triangles Flashcards
What are the functions of the vagina?
Female organ of copulation, lower portion of birth canal, and excretory duct for the products of menstruation
How does the vaginal canal communicate with the cervical canal above it?
Through the external os
How does the vaginal canal communicated with the vestibule below it?
Through the vaginal orifice
Where do the fundus of the bladder and the urethra lie in reference to the vagina?
Anterior
Where does the rectum lie in reference to the vagina?
Posterior
What is the recess between the cervix and the walls of the vagina?
Fornix
What are the three parts of the fornix?
Anterior, two lateral, and posterior fornices
What is the superior, expanded portion of the vagina below the cervix?
Vaginal vault
What is the vagina supported by?
Levator ani, perineal body, perineal membrane, ligament (pubocervical, transverse cervical, uterosacral)
What is the blood supply to the vagina?
Uterine artery and vaginal artery
What artery is the direct supply to the upper part of the vagina specifically?
Uterine artery
What are the lymphatics that are associated with the vagina?
Internal iliac (upper 3/4) and superficial inguinal nodes (lower 1/4)
What is the innervation of the vagina?
Pudendal nerve (lowermost part) and uterovaginal plexus
What specific area of the only part of the vagina that really has sensation?
Lowermost part
What is rectocele?
Bulging of the rectum into the posterior wall of the vagina
Rectocele can cause what issue?
Difficulty in defecation
What is cystocele?
Bulging of the bladder into the anterior wall of the vagina
Cystocele can cause what issue?
Difficulty in micturition
What is uterine prolapse?
When the uterus slips down into the vagina and descends to an abnormally low level in the pelvis
What are risk factors associated with uterine prolapse?
Multiple births, retroverted uterus
During uterine prolapse, what can also happen to the cervix?
It may protrude externally through the vaginal orifice
Inflammation of uterine lining, retroverted uterus, or traction of a large uterus on the uterosacral ligament may cause what type of pain?
Sacral
Severe menstrual cramps may be associated with subluxations of what location?
L1 or L2
What is the part of the trunk below the pelvis diaphragm called?
Perineum
The perineum has the same boundaries as what structure?
Pelvic outlet
What shape is the perineum?
Diamond
What divides the perineum into two triangles?
A transverse line connecting the two ischial tuberosities
What are the two triangles creating from the division of the perineum?
Urogenital triangle (anteriorly) and anal triangle (posteriorly)
In anatomical position, which triangle of the perineum lies in the horizontal plane?
Urogenital
In anatomical position, which triangle of the perineum is tilted upward?
Anal triangle
What are the boundaries of the urogenital triangle?
Pubic symphysis (anterior), ischiopubic rami (anterolateral), transverse line through ischial tuberosities (posterior)
What are the layers of the urogenital triangle?
Skin, superficial perineal pouch, perineal membrane, deep perineal pouch, inferior fascia of the pelvis diaphragm
What are the two layers of the superficial perineal pouch?
Superficial perineal fascia and deep perineal fascia
Which layer of the superficial perineal pouch includes a fatty layer superficially and a membranous layer that is deep?
Superficial perineal fascia
What is another name for the membranous (deep) layer of the superficial perineal fascia?
Colles’ fascia
Colles’ fascia is continuous with what structures?
Both the dartos layer of the scrotum and Scarpa’s fascia
What part of the superficial perineal pouch intimately invests the muscles of that area?
Deep perineal fascia
(Colles’ fascia) is fused anteriorly with what ligament?
Suspensory ligament of the penis (or clitoris)
The bulb and crus of the superficial perineal pouch are composed with what type of tissue?
cavernous erectile CONNECTIVE tissue (NOT MUSCLE)
What is an episiotomy?
Incision done during parturition from the posterior vaginal wall to the perineal body
What is the purpose of an episiotomy?
To prevent uncontrolled muscle tearing during parturition
What is the fibromuscular mass located in the center of the perineum between the anal canal and bulb of the penis (or vagina)?
Perineal body
The perineal body is an important attachment site for which muscles?
Superficial transverse perineal, deep transverse perineal, bulbospongiosus, levator ani, and sphincter ani externus
What muscle is important to note that does NOT have an attachment to the perineal body?
Ischiocavernosus
What is the origin of the superficial transverse perineal muscle?
Ischial tuberosity
What is the insertion of the superficial transverse perineal muscle?
Perineal body
What is the innervation of the superficial transverse perineal muscle?
Perineal branch of pudendal nerve
What is the function of the superficial transverse perineal muscle?
Stabilizes the perineal body
What is the origin of the ischiocavernosus muscle?
Medial surface of ischial tuberosity and ischiopubic ramus
What is the insertion of the ischiocavernosus muscle?
Crus of the penis or clitoris
What is the innervation of the ischiocavernosus muscle?
Perineal branch of pudendal nerve
What is the function of the ischiocavernosus muscle?
Impedes venous return by compressing the crus of the penis or clitoris, thereby maintaining erection
What is the origin of the bulbospongiosus muscle in males?
Perineal body, median raphe of the bulb of the penis
What is the insertion of the bulbospongiosus muscle in males?
Corpus spongiosum, deep fascia on dorsum of penis
What is the innervation of the bulbospongiosus muscle in both sexes?
Perineal branch of pudendal nerve
What is the function of the bulbospongiosus muscle in males?
Impedes venous return by compression the bulb of the penis, thereby maintaining erection. It also constricts the corpus spongiosum to empty the urethra at the end of micturition and during ejaculation
What is the origin of the bulbospongiosus muscle in females?
Perineal body, fibers surround the bulb of the vestibule and vagina
What is the insertion of the bulbospongiosus muscle in females?
Pubic arch and corpus cavernosum of clitoris
What is the function of the bulbospongiosus muscle in females?
Constricts the vaginal orifice and maintains erection of clitoris
What are the two ovoid glands located in the superficial perineal pouch of the female?
Greater vestibular glands
The greater vestibular glands lie where in reference to the bulb of the vestibule?
Posterior
Where do the ducts of the greater vestibular glands open?
Into the vestibule along the posterolateral margin of the vaginal orifice
The greater vestibular gland is homologous to what male structure?
Bulbourethral gland
What is the main function of the greater vestibular glands?
Lubrication of the vagina during sexual intercourse
Parasympathetic activation of what cord levels occur during erection?
S2, S3, S4
What arteries are dilated within the corpora cavernosa during erection?
Small, coiled arteries called helicine arteries
What two muscles are important for maintain erection?
Bulbospongiosus and ischiocavernosus
Where is the deep perineal pouch located?
Between the perineal membrane and inferior fascia of the pelvic diaphragm
Where is the superficial perineal pouch located?
Between the superficial perineal fascia and the perineal membrane
What are the contents of the superficial perineal pouch?
Perineal body, superficial transverse perineal muscle, ischiocavernosus muscle, crura of the penis (or clitoris), bulbospongiosus muscle, bulb of the penis (or vestibule), greater vestibular gland (females), branches of the internal pudendal artery and pudendal nerve
What are the contents of the deep perineal pouch?
Deep transverse perineal muscle, external urethral sphincter, intermediate part of the urethra (membranous part), bulbourethral gland (males), branches of the internal pudendal artery and pudendal nerve
What is the origin of the deep transverse perineal muscle?
Medial surface of ischial ramus
What is the insertion of the deep transverse perineal muscle?
Perineal body and median raphe (males) or wall of the vagina (females)
What is the innervation of the deep transverse perineal muscle?
Perineal branch of the pudendal nerve
What is the function of the deep transverse perineal muscle?
Stabilizes the perineal body and supports the prostate gland or vagina
What part of the external urethral sphincter in males is the true anatomical sphincter which encircles the urethra below the prostate?
Inferior part
Which part of the external urethral sphincter in males is the trough-like portion which extends up to the neck of the bladder, investing anterior part of prostatic urethra within the isthmus of the prostate?
Superior part
What structure is commonly damaged during parturition and results in what issue?
External urethral sphincter, urinary incontinence
What part of the female external urethral sphincter muscle is the inferior part that encircles both the urethra and vagina?
Sphincter urethrovaginalis
What part of the female external urethral sphincter muscle originates from the ischiopubic ramus on each side and forms a band anterior to the urethra?
Compressor urethrae
What part of the female external urethral sphincter muscle is the trough-like portion which extends to the neck of the bladder?
Superior part
What is the nerve supply to the external urethral sphincter muscle in both sexes?
Perineal branch of pudendal
What is the function of the external urethral sphincter muscle (in both sexes)?
Compresses urethra at the end of micturition
What are the two glands that lie posterolateral to the intermediate (membranous) part of the urethra in the male?
Bulbourethral glands
Where do the ducts of the bulbourethral glands empty?
After passing downward through the perineal membrane into the bulb of the penis, they empty into the spongy urethra
The bulbourethral glands are homologous to what female structure?
Greater vestibular glands
What type of substance is created by the bulbourethral glands of the male?
Mucous-like
What are the boundaries of the anal triangle?
Transverse line through ischial tuberosities (anterior), sacrotuberous ligaments (posterolateral), tip of the coccyx (posterior)
Which triangle of the perineum divisions is equal in both sexes?
Anal triangle
What is contained in the anal triangle?
Anal canal, external anal sphincter, and ischioanal fossa
What is the space which lies on either side of the anal canal that extends between the skin of the anal region below and the inferior surface of the pelvis diaphragm above?
Ischioanal fossa
What forms the lateral wall of the ischioanal fossa?
Obturator fascia
What is contained within the ischioanal fossa?
Fat, pudendal canal (and contents), inferior rectal nerve and vessels, perineal branch of posterior cutaneous nerve of thigh
The anterior recesses of the ischioanal fossa extend where?
Anteriorly into the urogenital triangle
What ligament connects the external anal sphincter to coccyx?
Anococcygeal ligament
The pudendal canal (formed by obturator fascia) is located on what part of the ischioanal fossa?
Lateral wall
What structures are transmitted through the pudendal canal?
Internal pudendal vessels, pudendal nerve
What is the purpose of fat in the ischoanal fossa?
Allows distention of the anal canal