Ischioanal Fossa and Pelvic Diaphragm Flashcards
What are the borders of the perineum?
Anteriorly- Pubic symphysis
Posteriorly- Coccyx
Laterally- Ischial tuberosity
The diamond shape of the perineum is best appreciated when the patient is in the _________ position.
Lithotomy
What two structures separate the pelvic cavity from the perineum?
-
Urogenital diaphragm
- Found in the urogenital triangle
-
Pelvic diaphragm
- Found in the anal triangle
NOTE: These two diaphragms are muscles and henceforth can be exercised and strengthened.
Between the 2 diaphragms is a fibrous block of tissue that serves as an attachment of the muscle found in the urogenital and pelvic diaphragm called the __________.
Perineal body
NOTE: In females it can be palpated between the vaginal orifice and the anus.
Function of the thoracoabdominal diaphragm
- Support pelvic organs
- Increase intra-abdominal/pelvic pressures upon contraction.
NOTE: The volume will decrease but the pressure will increase.
What are the two muscles of the pelvic diaphragm?
-
Levator ani
- Pubococcygeus
- Iliococcygeus
- Puborectalis.
- Coccygeus
What are the origins of the iliococcygeus muscle?
- Tendinous arch of the obturator internus muscle
- Inner part of the ischium
What two muscles originate from the tendinous arch?
Iliococcygeus
Ishiococcygeus
The anorectal junction is kinked 80 degrees by the ________.
Puborectal sling
NOTE: The puborectal ring has a certain muscle tone and pulls the rectal-anal junction anteriorly producing a kink which helps to control defecation
Which two muscles make up the puborectal ring?
Puborectalis
External anal sphincter
NOTE: Relaxation of the puborectal sling allows the rectum to straighten and the feces to drop down for defecation
Which muscle is most often town during childbirth?
Pubococcygeus
NOTE: Tearing of the pubococcygeus results in fecal incontinence
What are the two types of episiotomy?
-
Median episiotomy
- Take a scapel and run it from the vagina to about halfway to the anus.
-
Mediolateral episotomy
- Run the scapel posteriorly and then move laterally to avoid the perineal body
NOTE: The purpose of an episiotomy is to make the opening of the birth canal larger. If this procedure is performed it is important to avoid cutting the levator ani. Cutting the levator ani will weaken the pelvic floor and make the woman more prone to fecal incontinence.
What is the function of the broad ligament?
Serves as mesentery for the uterus, ovaries, and uterine tube
The ________ is subserous connective tissue that becomes thickened as the blood vessels come into the uterus and vagina. As it develops, it forms the cardinal ligament.
Endopelvic fascia
NOTE: The endopelvic fascia provides passive support but if this connective tissue becomes stretched becuase of childbith or lack of well developed pelvic muscles then you can’t restore it.
What is the most important ligament of the uterus?
Transverse cervical fascia (cardinal ligament)
NOTE: This ligament comes infrom laterally around the blood vessels going to the uterus and vagina and it provides passive support that can be surgically tightened to raise the contents of the pelvic cavity.
The sigmoid colon enters the pelvic cavity and terminates as the _________.
Rectum
NOTE: The rectum passes through the pelvic diaphragm and becomes the anal canal.
In a digital examination of the rectum of a male, doctor can palpate which three structures?
- Prostate
- Seminal vesicle
- Bladder
NOTE: The prostate is exam is to assess whether the prostate is hard or soft. It should be soft and smooth; if it is hard or lumpy that can be an indication of a tumor.
Only the (lower/upper) part of the rectum is covered by peritoneum.
Upper
NOTE: This part of the rectum is consider intraperitoneal. The terminal part of the rectum is extra-peritoneal and has no peritoneum and is beyond the serous membrane.
The ____________ is the lowest spot in the female’s body where seroud fluid may be drained.
The space between cervix and the posterior wall of the vagina is the _____________.
Posterior fornix
NOTE: The space betweeen the fornix and the pouch of Douglas is very thin. It is only peritoneum and the vaginal wall separating these two spaces so this a way a surgeon can gain access to the pelvic cavity either to drain fluid from ascites or infection or to inspect the ovaries.