Trans - Perineum and External Genitalia Flashcards
What is immediately anterior to the perineum?
Pubic symphysis
The ischial tuberosities are located _____ to the perineum
Lateral
The anal canal is found in the
Anal triangle
What encloses the urogenital triangle?
Perineal membrane
Ischiocavernosus: action
Forces blood from cavernous spaces in crura into distal parts of corpora cavernosa
What muscles compress the bulb of the penis and the corpora spongiosum?
Bulbospongiosus
Bulbocavernosus
Aids pelvic diaphragm in supporting pelvic viscera
Superficial transverse perineal muscles
Bartholin’s gland: function
Lubricates vaginal canal by secreting mucus
What is located immediately inferior to the deep perineal space?
Perineal membrane
Most prominent blood vessel in the deep perineal space
Deep dorsal vein of the penis / clitoris
Lubricates and cleanses the urethra during ejaculation
Cowper’s gland
The deep post-anal space is where the ____ communicate
Ischiorectal fossa
Medial boundary of the ischiorectal fossa
External anal sphincter
What nerves are in the ischiorectal fossa?
- Perforating cutaneous branches of S2 and S3
2. Perineal branch of S4
Voluntary sphincter surrounding the inferior 2/3 of the anal canal
External anal sphincter
Prolapse of the bladder and / or uterus is caused by:
Stretching or tearing of the perineal body
Location of the perineal body
Central point of perineum
What four muscles converge at the central point of the perineum?
- Bulbocavernosus
- Superficial transverse perineal
- External anal sphincter
- Levator ani
The central point of the perineum is important because:
It determines whether the surgeon should go medial or mediolateral during an episiotomy
Episiotomy: definition
Surgical incision of perineum and interoposterior vaginal wall performed just prior to delivery to prevent perineal lacerations
This type of episiotomy heals faster
Medial
Episiotomy in which muscles are severed
Mediolateral
Why are mediolateral episiotomies done?
If the length of the perineal body is less than 3mm, a mediolateral episiotomy must be performed to prevent complications
Perineal lacerations are often caused by
Unprotected childbirth
What muscles are involved in a first degree perineal laceration?
None
T/F: A second degree perineal laceration does not involve urogenital structures
F
What muscle is cut in a third degree perineal laceration?
External anal sphincter
Primary function of external genitalia
Copulation and parturition
T/F: During the sixth week of gestation, genitalia can be differentiated
F
At what age of gestation are sex indicators present?
Seventh week AOG
The phallus is formed from what embryonic structure
Genital tubercle
In males, the urethral plate is formed from what embryonic structure
Epithelial lining of groove from endoderm
At what age of gestation is the penile urethra formed?
3rd month AOG
When is the definitive external urethral meatus formed?
4th month AOG
What structure moves caudally to form the scrotal swellings?
Genital swellings
What embryonic structure becomes the clitoris?
Genital tubercle
In females, the urethral folds form the _______
Labia minora
The labia majora are formed when the _______ enlarge greatly
Genital swellings
The area between the hymen and the labia majora
Vestibule
Male copulatory organ and outlet for urine and semen
Penis
Location of the root of the penis
Superficial perineal pouch
What structure attaches to the pubis?
Crura