Blue Boxes Flashcards
What are the 4 variations in pelves?
Android
Anthropoid
Gynecoid
Platypelloid
Which of the following is the normal female type of pelvis?
A. Android
B. Anthropoid
C. Gynecoid
D. Platypelloid
Describe it!
C. Gynecoid
[round pelvic inlet with wide transverse diameter]
Which TWO of the following pelvic shapes in a woman present hazards to successful vaginal delivery of a fetus?
A. Android
B. Anthropoid
C. Gynecoid
D. Platypelloid
D and A
Which TWO of the following are most common in males?
A. Android
B. Anthropoid
C. Gynecoid
D. Platypelloid
A and B
Which TWO of the following are most common in white females?
A. Android
B. Anthropoid
C. Gynecoid
D. Platypelloid
A and C
Which TWO of the following are most common in black females?
A. Android
B. Anthropoid
C. Gynecoid
D. Platypelloid
B and C
Which of the following is uncommon in both sexes?
A. Android
B. Anthropoid
C. Gynecoid
D. Platypelloid
D. Platypelloid
What makes up the narrowest fixed distance in the pelvis through which the baby’s head must pass in a vaginal delivery? How is this distance measured?
The minimum AP diameter of the lesser pelvis = The true (obstetrical) conjugate from the middle of the sacral promontory to the posterosuperior margin (closest point) of the pubic symphysis
How is the true obstetrical conjugate (minimum distance necessary for successful vaginal delivery) measured?
Cannot be measured directly during pelvic exam d/t presence of bladder. Diagonal conjugate is measured by palpating the sacral promontory with the tip of middle finger, using other hand to mark level of inferior margin of pubic symphysis on examining hand. After examining hand is withdrawn, the distance between the tip of index finger and marked level of pubic symphysis is measured to estimate true conjugate, which should be 11 cm or greater
______ _____ = passageway through the pelvic inlet, lesser pelvis, and pelvic outlet
Pelvic canal
What is the narrowest part of the pelvic canal through which a baby’s head must pass at birth? (Note this is referring to the NON-fixed distance)
The interspinous distance = distance between ischial spines extending toward each other
During a pelvic exam, if the ___ _____ are far enough apart to permit 3 fingers to enter the vagina side by side, the ____ ____ is considered sufficiently wide to permit passage of an average fetal head at full term
Ischial tuberosities; subpubic angle
AP compression of the pelvis occurs during crush accidents (as when a heavy object falls on the pelvis); this type of trauma commonly produces what type of fracture?
Fractures of pubic rami
When the pelvis is compressed laterally, the _____ and _____ are squeezed toward each other and may be broken
Acetabula; ilia
Fractures of the bony pelvic ring are almost always multiple fractures or a fracture combined with a joint ______. Some pelvic fractures result from the tearing away of bone by the strong ligaments associated with the _____ joints
Dislocation; SI
What are the weak areas of the pelvis where fractures commonly occur?
Pubic rami
Acetabula (or area surrounding them)
Region of SI joints
Alae of ilium
Pelvic fractures may cause injury to pelvic soft tissues, blood vessels, nerves, and organs. Fractures in the ____ ____ area are relatively common and are often complicated because of their relationship to the urinary bladder and urethra, which may be ruptured or torn
Pubo-obturator
Falls on the feet or buttocks from a high ladder may drive the head of the femur through the ______ into the pelvic cavity, injuring pelvic viscera, nerves, and vessels.
In individuals younger than 17 y/o, the acetabulum may fracture through the _____ cartilage into its 3 developmental parts or the bony acetabular margins may be torn away
Acetabulum
Triradiate
A double break in the continuity of the anterior pelvic ring, which is common pelvic injury in MVAs, causes instability but usually little displacement. Injury to what structures is likely?
Visceral injury is likely - especially GU injuries
The larger cavity of the ____ ____ in females increases in size during pregnancy. This change increases the circumference of the ____ pelvis and contributes to increased flexibility of the pubic symphysis
Interpubic disc; lesser
Increased levels of sex hormones and the presence of the hormone _____ cause the pelvic ligaments to relax during the latter half of pregnancy — what does this allow for?
Relaxin; allows increased movement at pelvic joints
Relaxation of the ______ joints and pubic symphysis in latter half of pregnancy permits as much as 10-15% increase in diameters — mostly transverse, including interspinous distance, facilitating passage of fetus through pelvic canal. The _____ is also able to move posteriorly.
SI; coccyx
What is the one diameter that remains unchanged in pregnancy?
True (obstetrical) diameter between the sacral promontory and the posterosuperior aspect of the pubic symphysis
Relaxation of SI ligaments in pregnancy causes the interlocking mechanism of the SI joint to become less effective, permitting greater rotation of the pelvis and contributing to the lordotic “swayback” posture often assumed during pregnancy with the change in center of gravity.
What does this mean for the risk of joint dislocation in pregnancy?
Risk increases!
_________ = defect allowing part of a vertebral arch (posterior projection from vertebral body that surrounds the spinal canal and bears articular, transverse, and spinal processes) to be separated from its body
Spondylosis
What is the result of spondylosis of L5?
Separation of vertebral body from part of its vertebral arch bearing the inferior articular processes
The inferior articular processes of L5 normally interlock with articular processes of the sacrum. When the defect is bilateral, the body of L5 may slide anteriorly on the sacrum (spondylolisthesis) so that it overlaps the sacral promontory
The intrusion of L5 body into the pelvic inlet reduces the AP diameter of the pelvic inlet, which may interfere with parturition (childbirth). It may also compress spinal nn., causing low back or lower limb pain
How do obstetricians test for spondylolisthesis?
They run their fingers along lumbar spinous processes; an abnormally prominent L5 spinous process indicates that the anterior part of L5 and the vertebral column superior to it may have moved anteriorly relative to the sacrum and the vertebral arch of L5
Medical images such as sagittal MRI are used to confirm, and to measure AP diameter of pelvic inlet
The fact that the ureter passes immediately inferior to the uterine artery near the lateral part of the fornix of the vagina is clinically important. During what surgical procedure does this relationship become important and why?
During hysterectomy, the ureter is in danger of being inadvertently clamped, ligated, or transected while the surgeon is ligating and severing the uterine artery to remove the uterus.
The point at which the uterine artery and ureter cross lies approximately 2 cm superior to the ischial spine
The _______ are vulnerable to injury when the ovarian vessels are ligated during an ovariectomy because these structures are close to each other as they cross the pelvic brim
Ureters
Occasionally, the ____ ____ artery becomes stenotic due to atherosclerotic cholesterol deposit, or it is surgically ligated to control pelvic hemorrhage.
Because of the numerous anastomoses between the artery’s branches and adjacent arteries, the ligation does not stop blood flow but it does reduce blood pressure, allowing _______ to occur
Internal iliac
Hemostasis
What are 4 examples of collateral pathways to the internal iliac artery that exist as pairs of anastomosing arteries?
Lumbar + iliolumbar aa.
Median sacral + lateral sacral aa.
Superior rectal + middle rectal aa.
Inferior gluteal + profunda femoris aa.
[blood flow in the artery is maintained, although it may be reversed in the anastomotic branch; the collateral pathways may maintain the blood supply to the pelvic viscera, gluteal region, and genital organs]
During childbirth, the fetal head may compress the nerves of the mother’s _____ _____, producing pain in the lower limbs.
Sacral plexus
The _____ nerve is vulnerable to injury during surgery (e.g., during removal of cancerous lymph nodes from the lateral pelvic wall). Injury to this nerve may cause painful spasms of the adductor muscles of the thigh and sensory deficits in the medial thigh region
Obturator
The ureters may be injured during surgical procedures so they should be carefully identified in their course through the abdomen. What effect does traction on the ureters have during surgery?
May lead to delayed rupture of ureter, because it becomes gangrenous and ruptures 7-10 days later
When traction is necessary, it must be applied gently within a strictly limited range using padded, blunt retractors
When the ureters must be retracted during surgery, it is important to remember that although the blood supply to the abdominal segment of the ureter approaches from a _____ direction, that of the pelvic segment comes from a _____ direction
Medial; lateral
Acute obstruction of the ureters typically results from a _____ _____; symptoms depend on location, type, and size, and whether it is smooth or spiky. The pain caused is described as ______, which results from hyperperistalsis in the ureter, superior to the level of obstruction
Ureteric calculus; colicky
Ureter obstruction may occur anywhere, but what are the 3 most common sites?
- At junction of ureters and renal pelves
- Where the ureters cross external iliac a. and pelvic brim
- During their passage through the wall of the urinary bladder
What is the preferred imaging method for identifying ureteric calculi?
CT
Ureteric calculi may be removed by open surgery, endoscopy, or ______ which uses shock waves to break up a stone into small fragments that can be passed in the urine
Lithotripsy
Loss of bladder support in females by damage to the pelvic floor during childbirth or a lesion of nerves supplying them, or rupture of the fascial support of the vagina, the paracolpium can result in collapse of the bladder onto the anterior vaginal wall. What is this condition called, and what is the likely result when intra-abdominal pressure increases during processes such as defecation?
Cystocele = hernia of bladder
Bearing down causes anterior wall of the vagina to protrude through the vaginal orifice into the vestibule
Although the superior surface of the empty bladder lies at the level of the superior margin of the _____ _____, as the bladder fills it extends superiorly into the loose areolar tissue between the parietal peritoneum and anterior abdominal wall. The bladder then lies adjacent to this wall without the intervention of peritoneum. Consequently, the distended bladder may be punctured via ______ ______, or approached surgically for the introduction of indwelling catheters or instruments without traversing the peritoneum. Urinary calculi, foreign bodies, and small tumors may also be removed from the bladder through a suprapubic extraperitoneal incision
Pubic symphysis; suprapubic cystotomy
Because of the superior position of the distended bladder, it may be ruptured by injuries to the inferior part of the anterior abdominal wall or by fractures of the pelvis. What complications might this lead to, especially considering superior rupture vs. posterior rupture?
The rupture may result in escape of urine extraperitoneally or intraperitoneally.
Rupture of the superior part of the bladder frequently tears the peritoneum, resulting in extravasation of urine into the peritoneal cavity.
Posterior rupture of the bladder usually results in passage of urine extraperitoneally into the perineum.
What instrument is passed into the bladder through the urethra to examine the interior and perform transurethral resection of a tumor?
Cystoscope (cystoscopy)
[using high frequency electrical current, the tumor is removed in small fragments that are washed from the bladder with water]
The female urethra is distensible because it contains considerable elastic tissue as well as smooth muscle. It can be easily dilated without injury. What does this mean for cystoscopy and catheterization in comparison with males?
It is easier to do these procedures in females than males
What characteristics of the female urethra make it higher risk for infection?
Short, more distensible, and open to exterior through vestibule of vagina
Many structures related to the antero-inferior part of the rectum may be palpated through its walls — what are some examples of structures that may be palpated via rectal exam?
Males: prostate, seminal glands, abnormal contents in rectovesical pouch
Females: cervix, abnormal contents in rectouterine pouch
Both sexes: pelvic surfaces of sacrum and coccyx, ischial spines and tuberosities, enlarged internal iliac LNs, pathological thickening of uretuers, swellings in ischioanal fossae, tenderness of an inflamed appendix if it descends into pararectal fossa
The internal aspect of the rectum can be examined with a _______, and biopsies of lesions may be taken through this instrument
During insertion of a ______, the curvatures of the rectum and its acute flexion at the rectosigmoid junction have to be kept in mind so the patient does not undergo unnecessary discomfort. The operator must also know that the ________, which provide useful landmarks for the procedure, may temporarily impede passage of these instruments
Proctoscope
Sigmoidoscope; transverse rectal folds
When resecting the rectum in males (e.g. during cancer treatment), the plane of the ______ septum (a fascial septum extending superiorly from the perineal body) is located so that the prostate and urethra can be separated from the rectum so that they are not damaged in surgery
Rectovesical
The common method of sterilizing males
Vasectomy (deferentectomy)
Can a vasectomy be reversed?
Yes, it is successful in favorable cases (pts <30 and <7 years post op) — the ends of the sectioned ductus deferentes are reattached under an operating microscope
Describe a vasectomy
Part of ductus deferens is ligated and/or excised through an incision in the superior part of the scrotum. Hence, the subsequent ejaculated fluid from the seminal glands, prostate, and bulbo-urethral glands contains no sperms. The unexpelled sperms degenerate in the epididymis and proximal part of the ductus deferens
Localized collections of pus (abscesses) in the seminal glands may have what major complication?
They may rupture, allowing pus to enter the peritoneal cavity
How are seminal glands palpated?
They can be palpated during a rectal exam, especially if enlarged or full. They are palpated most easily when the bladder is moderately full.
[They can also be massaged to release their secretions for microscopic examination to detect organisms that cause gonorrhea]
An enlarged prostate projects into the urinary bladder and impedes urination by distorting the prostatic urethra. The _____ ____ usually enlarges the most and obstructs the internal urethral orifice. The more the person strains, the more the valve-like prostatic mass occludes the urethra
Middle lobule
The prostate is examined for enlargement by digital rectal exam. The palpability of the prostate depends on what?
The fullness of the bladder; a full bladder offers resistance, holding the gland in place and making it more readily palpable
In advanced stages, prostatic cancer cells can metastasize in what 2 ways?
Via lymphatics — initially to internal iliac and sacral LNs and later to distant nodes
Via venous routes — by way of internal vertebral plexus to the vertebrae and brain
How are prostatic urethral obstructions treated?
Endoscopically — instrument is inserted transurethrally through the external urethral orifice and spongy urethra into the prostatic urethra. All or part of the prostate is removed (transurethral resection of the prostate)
In more serious cases of BHP, what structures are removed with the prostate?
Entire prostate removed + seminal glands, ejaculatory ducts, internal parts of deferent ducts (radical prostectomy)
[note that TURP and improved open operative techniques attempt to preserve nerves and blood vessels associated with capsule of prostate that pass to and from penis, increasing possibility for pts to retain sexual function as well as normal urinary control]
Because the female genital tract communicates with the peritoneal cavity through the abdominal ostia of the uterine tubes, infections of the vagina, uterus, and tubes may result in _______. Conversely, inflammation of a tube or ______, may result from infections that spread from the peritoneal cavity.
Peritonitis; salpingitis
A major cause of infertility in women is blockage of the uterine tubes, often the result of _______
Salpingitis
Patency of the uterine tubes may be determined by a radiographic procedure involving injection of a water-soluble radioopaque material or carbon dioxide gas into the uterus and tubes through the external os of the uterus. The contrast medium travels through the uterine cavity and tubes. Accumulation of fluid or appearance of gas bubbles in the pararectal fossae region indicates that the tubes are patent. What is this procedure called?
Hysterosalpingography
Patency of the uterine tubes can be assessed by _________ or hysterosalpingography
Endoscopy
Surgical method of birth control in females
Ligation of uterine tubes
After ligation of uterine tubes, what happens to oocytes that have been discharged from the ovaries?
They enter the tubes but then degenerate and are soon absorbed.
What are the 2 methods for ligation of the uterine tubes?
Abdominal (open) tubal ligation
Laparoscopic tubal ligation
______ = collections of pus that develop in uterine tube
Pyosalpinx
In cases of pyosalpinx, the tube may be partly occluded by adhesions. In these cases, the ______ (early embryo) may not be able to pass along the tube to the uterus, although sperms have obviously done so. When the _____ forms, it may implant in the mucosa of the uterine tube, producing an _______ _______ pregnancy
Morula; blastocyst; ectopic tubal
Although ectopic pregnancy may implant anywhere along the uterine tube, where is the most common location for implantation?
Ampulla
What is the most common location for ectopic pregnancy in general? What are some other possible locations for implantation?
Tubal ectopic pregnancy (may occur in infundibulum, ampulla, isthmus)
Other locations: ovary, abdomen, interstitium of uterine fundus, cervix
Complications of tubal ectopic pregnancy
Rupture of uterine tube —> severe hemorrhage into abdominopelvic caivty during first 8 weeks
Occasionally, the ______ between the uterine tube and the ovary contains embryonic remnants. The _______ forms from remnants of the mesonephric tubules of the mesonephros, the transitory embryonic kidney. There may also be a persistent duct associated, which is a remnant of the mesonephric duct which forms the ductus deferens and ejaculatory duct in males. It lies between the layers of the _____ ligament along each side of the uterus and/or vagina.
Mesosalpinx; epophoron; broad
A _____ _____ is sometimes attached to the infundibulum of the uterine tube. It is the remains of the cranial end of the mesonephric duct that forms the ____ _____
Vesicular appendage; ductus epididymis
Although remnants of embryonic ducts form vestigial structures that are benign, they occasionally have what complication?
Accumulation of fluid and formation of cysts (i.e. Gartner’s duct cysts)
Incomplete fusion of the embryonic ________, from which the uterus is formed, results in a variety of congenital anomalies, ranging from formation of a unicornate uterus (receiving a uterine duct only from the right or left) to duplication in the form a _______ uterus, doubled uterine cavities, or a completely doubled uterus = ________
Paramesonephric ducts; bicornate; uterus didelphys
When intra-abdominal pressure is increased, the normally anteverted and anteflexed uterus is pressed against the ________..
Bladder
However, the uterus may assume other dispositions, including excessive anteflexion, anteflexion with retroversion, and retroflexion with retroversion. Instead of pressing against the bladder with increasing abdominal pressure, what happens?
Pressure tends to push retroverted uterus into or even through the vagina. A retroverted uterus will not necessarily prolapse, but is more likely to do so. The situation is exacerbated in the presence of a disrupted perineal body or atrophic pelvic floor ligaments and muscles
______ ____ = indicator of softening of the uterine isthmus, when cervix feels as though it were separated from the body
Hegar sign
Softening of the isthmus is an early sign of _____
Pregnancy
The uterus is typically examined via bimanual palpation, but if this exam is not clear, what is the next step?
Uterus can be further stabilized via rectovaginal exam
T/F: at birth, the uterus is relatively large and has adult proportions — with body to cervical ratio 2:1
True; this is due to prepartum influence of maternal hormones. Several weeks later, childhood dimensions are obtained — body to cervical ratio 1:1
Because of the small size of the pelvic cavity during infancy, the _____ is mainly an abdominal organ. The ____remains relatively large throughout childhood.
Uterus; cervix
What happens to the uterus during puberty?
The uterus (especially its body) grows rapidly in size, once again assuming adult proportions (first time since birth)
Over the 9 months of pregnancy, the _____ uterus expands greatly to accommodate the fetus, becoming larger and increasingly ___-walled. At the end of pregnancy, the fetus “drops” as the head becomes engaged in the ______ pelvis. The uterus becomes nearly membranous, with the fundus dropping below its highest level, at which time it extends superiorly to the costal margin, occupying most of the abdominopelvic cavity
Gravid; thin; lesser
Immediately after delivery of a fetus, the large uterus becomes ____ walled and ______, but its size reduces rapidly. The multiparous non-gravid uterus has a large and ____ body and usually extends into the lower abdominal cavity, often causing a slight protrusion of the inferior abdominal wall in lean women
Thick; edematous; nodular
How is a papanicolaou smear performed?
Vaginal speculum used to enable inspection of cervix
Spatula placed in external os and rotated to scrape cellular material from mucosa of vaginal cervix; cytobrush then used to gather material from supravaginal cervical mucosa
Because no peritoneum intervenes between the anterior cervix and the base of the ______, cervical cancer may spread by contiguity to this organ. It may also spread by lymphogenous metastasis to external or internal iliac or _____ nodes. Hematogenous metastasis may occur via ______ veins or via internal vertebral venous plexus
Bladder; sacral; iliac
Owing to the frequency of uterine and cervical cancer, _______, or excision of the uterus, is a relatively common procedure — approached through the anterior abdominal wall or through the vagina
Hysterectomy
The vagina can be markedly distended, particularly in the region of the posterior part of the _____. For example, distension of this part allows palpation of the ____ _____ during a pelvic exam. The distension also accommodates the erect penis during intercourse
Fornix; sacral promontory
The vagina is especially distended by the fetus during parturition, particularly in the _____ direction when the fetus’ shoulders are delivered.
Lateral distension is limited by the _______, which project posteromedially, and the ______ ligaments extending from them to the lateral margins of the sacrum and coccyx. The birth canal is thus deep anteroposteriorly and narrow transversely at this point.
AP
Ischial spines; sacrospinous
Because of its relatively thin, distensible walls and central location within the pelvis, the _____, ____, and ______ can be palpated with gloved digits in the vagina and/or rectum. Pulsations of the ____ arteries may also be felt through the lateral parts of the fornix, as may irregularities of the ovaries such as cysts
Cervix; ischial spines; sacral promonotry; uterine arteries
Because of the close relationship of the vagina to adjacent pelvic organs, obstetrical trauma during long and difficult labor may result in what complications?
Weakness
Necrosis
Tears in vaginal wall that may form fistulas later between the vaginal lumen and lumina of adjacent bladder, urethra, rectum, and/or perineum
What types of fistulas in females allow urine to enter the vagina?
Vesicovaginal fistula — flow is continuous
Urethrovaginal fistula — only during micturition
Fecal matter may be discharged from the vagina when there is a ______ _____
Rectovaginal fistula
An endoscopic instrument called a ______ can be inserted through the posterior part of the vaginal fornix to examine the ovaries or uterine tubes (e.g. for presence of tubal pregnancy). Although this _____ procedure involves less disruption of tissue, it has largely been replaced by laparoscopy which provides greater flexibility for operative procedures and better visualization of pelvic organs
Culdoscope; culdoscopy
A pelvic abscess in the recto-uterine pouch can be drained through an incision made in the posterior part of the vagina fornix in a procedure called ______. Similarly, fluid in the peritoneal cavity (e.g., blood) can be aspirated by this technique
Culdocentesis
Visual exam of the pelvic viscera is especially useful in diagnosing many conditions affecting the pelvic viscera, such as ovarian cysts and tumors, _______ — which is the presence of functioning endometrial tissue outside the uterus, and ectopic pregnancy.
_______ involves inserting a scope into the peritoneal cavity through an approx. 2 cm incision below the umbilicus. Insufflation of inert gas creates a ________ to provide space to visualize, and the pelvis is elevated so that gravity will pull intestines into abdomen
Endometriosis
Laparoscopy; pneumoperitoneum
T/F: During laparoscopy, the uterus can be externally manipulated to facilitate visualization, or additional openings (ports) can be made to introduce other instruments for manipulation or to enable procedures like ligation of uterine tubes.
True
Several options are available to women to reduce the pain and discomfort of childbirth. What type has advantages for emergency procedures?
General anesthesia — renders mother unconscious so that she is unaware of labor and delivery
How does childbirth proceed while the mother is under general anesthesia?
Childbirth occurs passively under the control of maternal hormones with the assistance of the obstetrician
What types of regional anesthesia nerve blocks are done for women during childbirth?
Spinal block
Pudendal nerve block
Caudal epidural block
Are women who choose regional anesthesia typically aware of their uterine contractions and able to push actively during childbirth?
Yes
Regional anesthesia prior to childbirth may be administered as spinal anesthesia, a process in which anesthetic agent is introduced with a needle into the spinal _______ space at the _____ vertebral level. It produces complete anesthesia inferior to approximately _____-level.
Subarachnoid; L3-L4; waist
Describe the level of consciousness of the mother after spinal anesthesia is administered prior to childbirth
The perineum, pelvic floor, and birth canal are anesthetized, and motor and sensory functions of the entire lower limbs as well as sensation of uterine contractions are temporarily eliminated. The mother is conscious, but she must depend on electronic monitoring of uterine contractions.
[If labor is extended or the level of anesthesia is inadequate, it may be difficult or impossible to re-administer the anesthesia.]
Spinal anesthetic agent is heavier than CSF. What does this mean for patient positioning during childbirth?
Because the anesthetic agent is heavier than CSF, it remains in the inferior spinal subarachnoid space while the patient is inclined. The anesthetic agent circulates into the cerebral subarachnoid space in the cranial cavity when the patient lies flat following delivery. A severe headache is a common sequel to spinal anesthesia
A pudendal nerve block is a peripheral n. block that provides local anesthesia over the ____-____ dermatomes (majority of the perineum) and the inferior quarter of the vagina.
S2-S4
T/F: the pudendal n. block administered as local anesthetic for childbirth blocks pain from the superior birth canal including the uterine cervix and superior vagina
False — it does not block pain in those areas so the mother is able to feel uterine contractions
Can a pudendal n. block be re-administered if local anesthetic relief is not achieved?
Yes, but to do so may be disruptive and nvolve the use of a sharp instrument in close proximity to the infant’s head
The ______ ______ block is a popular choice for local anesthetic during participatory childbirth. It must be administered in advance of the actual delivery, which is not possible with a precipitous birth
Caudal epidural
How is a caudal epidural block administered?
Using an in-dwelling catheter in the sacral canal, enabling administration of more anesthetic agent for a deeper or more prolonged anesthesia if necessary
The caudal epidural block administered within the sacral canal, the anesthesia bathes the ___-____spinal nerve roots, including pain fibers from the uterine cervix an dsuperior vagina, and the afferent fibers from the pudendal n. Thus the entire birth canal, pelvic floor, and majority of the perineum are anesthetized, but the _____ _____ are not usually affected
S2-S4; lower limbs
The pain fibers from the uterine body (superior to the pelvic pain line) ascend to the inferior thoracic-superior lumbar levels; these and the fibers superior to them are not affected by a ______ ______ block, so the mother is aware of her uterine contractions. With this type of anesthesia, no “spinal headache” occurs because the vertebral epidural space is not continuous with the cranial extradural (epidural) space
Caudal epidural
During childbirth, the pelvic floor supports the fetal head while the cervix of the uterus is dilating to permit delivery of the fetus. The perineum, levator ani, and ligaments of the pelvic fascia may be injured during childbirth. The ______ and _____, the main and most medial parts of the levator ani are the muscles torn most often. These parts of the muscle are important because they encircle and support the urethra, vagina, and anal canal
Pubococcygeus; puborectalis
Weakening of the _______ _____ and pelvic fascia (e.g., tearing of the paracolpium) from stretching or tearing during childbirth, may decrease support for the vagina, bladder, uterus, or rectum, or alter the position of the neck of the bladder and the _______. These changes may cause ___________, characterized by dribbling of urine when intra-abdominal pressure is raised during coughing and lifting, for instance, or lead to the prolapse of one or more pelvic organs.
Levator ani; urethra; urinary stress incontinence
Parents wishing to participate actively in the birth of their baby may take prenatal training (e.g., Lamaze classes) — what is the primary purpose of this?
To train women to relax voluntarily the muscles of the pelvic floor while simultaneously increasing intra-abdominal pressure through contraction of the diaphragm and anterolateral abdominal wall muscles.
The aim of this method is to facilitate passage of the fetus through the birth canal, actively pushing to aid the uterine contractions that expel the baby without providing resistance caused by contraction of the pelvic muscles.
Except when defecating or urinating, the natural reflex is to contract the pelvic musculature in response to increased intra-abdominal pressure
The ____ ____ is an important structure, especially in women, because it is the final support of the pelvic viscera, linking muscles that extend across the pelvic outlet, supporting the overlying pelvic diaphragm.
Perineal body
Stretching or tearing the attachments of perineal muscles from the perineal body can occur during childbirth, removing support from the pelvic floor. As a result ______ of the pelvic viscera may occur, affecting the bladder through the urethra, or the uterus and/or vagina.
Prolapse
Besides childbirth, what might cause disruption of the perineal body?
Trauma
Inflammatory disease
Infection (leads to fistula to vestibule)
Attenuation of the perineal body, associated with diastasis of the puborectalis and pubococcygeus parts of the levator ani, may also result in the formation of a _____, ____, and/or _____, hernial protrusions of part of the bladder, rectum, or rectovaginal pouch, respectively, into the vaginal wall
Cystocele, rectocele; enterocele
During vaginal surgery or labor, an _______ (surgical incision of the perineum and inferoposterior vaginal wall) may be made to enlarge the vaginal orifice with the intention of decreasing excessive traumatic tearing of the perineum and uncontrolled jagged tears of the perineal muscles
Episiotomy
Routine prophylactic episiotomies are widely debated and declining in frequency. In what types of cases are these more likely to be done?
When descent of fetus is arrested or protracted, when instrumentation is necessary (e.g., use of obstetrical forceps), or to expedite delivery when there are signs of fetal distress
What is the major structure incised during a median episiotomy? What is the rationale for this type of episiotomy?
Perineal body
Rationale is that scar produced as wound heals will not be greatly different from the fibrous tissue surrounding it. Also, because the incision extends only partially into this fibrous tissue, some surgeons believe that the incision is more likely to be self-limiting resisting further tearing
When further tearing occurs despite an episiotomy, what structures have the potential for damage?
Anus
External anal sphincter
Anovaginal fistula also possible
Recent studies indicate _____ episiotomies are associated with an increased incidence of severe lacerations, associated in turn with an increased incidence of long term incontinence, pelvic prolapse, and anovaginal fistulae
______ episiotomies appear to result in lower incidence of severe laceration and are less likely to be associated with damage to the anal sphincters and canal
Median
Mediolateral
What is the typical mechanism of injury when a rupture of the intermediate part of the urethra occurs in males?
Fracture of the pelvic girdle — especially those resulting from separation of the pubic symphysis and puboprostatic ligaments
What is the result of rupturing the intermediate part of the urethra in males?
Extravasation of urine and blood into the deep perineal pouch; the fluid may pass superiorly through the urogenital hiatus and distribute extraperitoneally around the prostate and bladder
The common site of rupture of the spongy urethra and extravasation of urine is in the bulb of the penis. How does this injury usually occur?
Usually results from forceful blow to the perineum (straddle injury), such as falling on a metal beam or, less commonly, from the incorrect passage of transurethral catheter or device that fails to negotiate the angle of urethral catheter or device that fails to negotiate the angle of the urethra in the bulb of the penis
Rupture of the corpus spongiosum and spongy urethra results in urine passing from it into the __________. The attachments of the perineal fascia determine direction of flow of extravasated urine. Urine may pass into loose CT in the _____, around the penis, and superiorly — deep to the membranous layer of subcutaneous CT of inferior anterior abdominal wall.
Superificial perineal space; scrotum
When extravasation of urine occurs in males, why can it not pass far into the thighs?
Because the membranous layer of superficial perineal fascia blends with the fascia lata, enveloping the thigh muscles, just distal to the inguinal ligament
[also cannot pass posteriorly into anal triangle, because the superficial and deep layers of perineal fascia are continuous with each other around the superficial perineal muscles and with the posterior edge of the perineal membrane between them]
How does starvation lead to rectal prolapse?
The fat bodies of the ischiorectal fossae are among the last reserves of fatty tissue to disappear with starvation. In the absence of the support provided by the ischio-anal fat, rectal prolapse is relatively common
The ischioanal fossae are occasionally the sites of infection, which may result in formation of ischio-anal abscesses. These collections of pus are painful. What are 4 primary ways in which infections may reach the ischio-anal fossae?
— after cryptitis (inflammation of anal tissues)
— extension from a pelvirectal abscess
— after a tear in the anal mucous membrane
—from a penetrating wound in the anal region
What are diagnostic signs of an ischio-anal abscess?
Fullness and tenderness between the anus and ischial tuberosity
What happens when a peri-anal abscess ruptures spontaneously?
It opens into the anal canal, rectum, or peri-anal skin. Because the ischio-anal fossae communicate posteriorly through the deep posterior anal space, an abscess in one fossa may spread to the other one, and form a semi-circular “horseshoe shaped” abscess around the posterior aspect of the anal canal
In chronically ______ persons, the anal valves and mucosa may be torn by hard feces. An _____ _____ (slit-like lesion) is usually located in the posterior midline, inferior to the anal valves. It is painful because this region is supplied by sensory fibers of the inferior rectal nn.
Constipated; anal fissure
A peri-anal abscess may follow infection of an anal fissure, and the infection may spread to the ________ and form abscesses there, or spread into the pelvis and form a ______ abscess
Ischio-anal fossae; pelvirectal
What are some causes of anal fistula?
Spread of anal infection and cryptitis (inflammation of an anal sinus)
With an anal fistula, one end opens into the ______, and the other opens into an abscess in the ______ or into the perianal skin
Anal canal; ischio-anal fossa
Prolapses of rectal mucosa containing the normally dilated veins of the internal rectal venous plexus
Internal hemorrhoids
What causes internal hemorrhoids
Breakdown of the muscularis mucosae, a smooth muscle layer deep to the mucosa
Internal hemorrhoids that prolapse into or through the anal canal are often compressed by the contracted ______, impeding blood flow. As a result, they tend to ______ or _______
Sphincters; strangulate; ulcerate
Because of the presence of abundant arteriovenous anastomoses, bleeding from internal hemorrhoids is characteristically _______ in color
Bright red
The current practice is to treat only _____, _____ internal hemorrhoids
Prolapsed, ulcerated
Thromboses in the veins of external rectal venous plexus, covered by skin
External hemorrhoids
Predisposing factors for external hemorrhoids
Pregnancy
Chronic constipation
Prolonged toilet sitting/straining
Any disorder that impedes venous return, including increased intra-abdominal pressure
The anastomoses between the superior, middle, and inferior rectal veins form clinically important communications between the portal system and systemic system. The superior rectal vein drains into the _____ vein, whereas the middle and inferior rectal veins drain through the systemic system into the _______. Any abnormal increase in pressure in the valveless portal system or veins of the trunk may cause enlargement of the superior rectal veins, resulting in an increase in blood flow or stasis in the _______ rectal venous plexus
Inferior mesenteric; IVC; internal
In the portal HTN that occurs in relation to hepatic cirrhosis, the portocaval anastomosis between the superior and middle and inferior rectal veins, along with the portocaval anastomoses elsewhere, may become _______. It is important to note that the veins of the rectal plexuses normally appear this way (dilated and tortuous), even in newborns, and that _____ hemorrhoids occur most commonly in the absence of portal HTN
Varicose; internal
Stretching of the _____ n. During a traumatic childbirth can result in damage to this n., leading to possible anorectal incontinence
Pudendal
Slightly conical instruments for exploring and dilating a constricted urethra
Urethral sounds
What part of the male urethra is most susceptible to damage during urethral catheterization?
A short segment of the intermediate part of the spongy urethra — because the urethral wall is thin and the angle that must be negotiated to enter this area, the wall is vulnerable to rupture
What is the least distensible part of the male urethra?
The intermediate part; which runs infero-anteriorly as it passes through the external urethral sphincter
What condition may result from external trauma of the penis or infection of the urethra, and may be tx by a urethral sound used to dilate the area?
Urethral stricture
The ____ urethra in males will expand enough to permit passage of an instrument approximately 8 mm in diameter. The _____ urethral orifice is the narrowest and least distensible part of the urethra
Spongy; external
The _____ is easily distended. In males with large indirect inguinal hernias, for example, the intestine may enter this area, making it as large as a soccer ball
Scrotum
Inlammation of the testes which may occur in the setting of mumps
Orchitis
What conditions may lead to distension/enlargement of the scrotum?
Indirect inguinal hernias
Orchitis
Bleeding in subcutaneous tissue
Chronic lymphatic obstruction
Which testicle commonly lies more inferior than the other?
Left
Common congenital anomaly of the penis, in its most common form, the external urethral orifice is on the ventral aspect of the glans penis
Hypospadias (glanular hypospadias in this case)
______ or _____ hypospadias occur when the external urethral orifice is on the urethral surface of the penis
Penile; peno-scrotal or scrotal
What is the embryological basis of penile and penoscrotal hypospadias?
Failure of the urogenital folds to fuse on the ventral surface, completing the formation of the spongy urethra
It is also believed that this condition is associated with an inadequate production of androgens by the fetal testes
In an uncircumcised penis, the _____ covers all or most of the glans penis, which is usually sufficiently elastic for it to be retracted over the glans
Prepuce
In some males, the prepuce fits tightly over the glans and cannot be retracted easily = ________
Phimosis
As there are modified sebaceous glands in the prepuce, the oily secretions of cheesy consistency from them accumulate in the _______, located between the glans and prepuce, causing irritation
Preputial sac
Condition in which retraction of the prepuce over the glans penis constricts the neck of the glans so much that there is interference with drainage of blood and tissue fluid
Paraphimosis
[glans may enlarge so much that the prepuce cannot be drawn over it — requiring circumcision be performed]
What 2 conditions in adult males typically require circumcision as tx?
Phimosis
Paraphimosis
Inability to obtain an erection may result from several causes. When a lesion of the _____ ____ or _____nerves results in an inability to achieve erection, a surgically implanted, semirigid or inflatable penile prosthesis may assume the role of the erectile bodies, providing the rigidity necessary to insert and move the penis within the vagina during intercourse
Prostatic plexus; cavernosus
What are some conditions that lead to erectile dysfunction?
CNS (hypothalamic) and endocrine (pituitary or testicular) disorders leading to reduced testosterone
Nerve fibers may fail to stimulate erectile tissues or blood vessels may be insufficiently responsive
In many cases of ED, medications or injections may increase blood flow into the ____ ____ by causing relaxation of smooth muscle
Cavernous sinusoids
What is removed in the process of female circumcision, which is still performed in some cultures?
Prepuce of clitoris, commonly also removes part or all of clitoris and labia minora
The highly vascular _____ of the vestibule are susceptible to disruption of vessels as the result of trauma (e.g., athletic injuries such as jumping hurdles, sexual assualt, and obstetrical injury)
Bulbs
Vulvar trauma often results in _______ (localized collections of blood) in the labia majora
Vulvar hematomas
What is the site of most vulvar adenocarcinomas?
Greater vestibular glands
Inflammation of the greater vestibular glands
Batholinitis
Infected greater vestibular glands may enlarge to a diameter of 4-5 cm and impinge on the wall of the _______. Occlusion without infection can result in accumulation of mucin = _______
Rectum; bartholin gland cyst
To relieve perineal pain during childbirth, a ____ nerve block may be performed by directly injecting anesthetic agent into the tissues surrounding this nerve.
Pudendal
Pudendal nerve block injections are made where the pudendal nerve crosses the lateral aspect of the _____ ligament, near its attachment to the ischial spine. The needle may be passed through the overlying skin, or more commonly through the ______ parallel to the palpating finger
Sacrospinous; vagina
[important to keep palpating finger between needle and infants head during procedure]
During childbirth, in order to abolish sensation from the anterior part of the perineum, an _____ nerve block is performed
Ilioinguinal
Why might a pt continue to complain of pain after administration of pudendal and ilioinguinal nn blocks?
Usually result of overlappin ginnervation by the perineal branch at the posterior cutaneous n. of the thigh
What muscles have common attachment to the perineal body in females, forming crossing beams over the pelvic outlet to support the perineal body?
Superficial transverse perineal m.
Bulbospongiosus m.
External anal sphincter m.
T/F: In the absence of the functional demands related to urination, penile erection, and ejaculation in males the superficial transverse perineal, bulbospongiosus, and external anal sphincter muscles are commonly relatively underdeveloped in women.
True
What type of exercises are recommended in order to prevent urinary stress incontinence and postpartum prolapse of pelvic viscera in females?
Kegel exercises
How do kegel exercises work?
Voluntary use of perineal mm., such as successive interruption of the urine flow during urination
Prepartum childbirth classes emphasize that in learning to voluntarily contract and relax the perineal mm, women become prepared to resist the tendency to contract the musculature during uterine contractions, allowing a less obstructed passage for the fetus and decreasing the likelihood of tearing the perineal mm.
The initial distension of the bulbospongiosus and transverse perineal mm. are thought to trigger the involuntary spasms of the perivaginal and levator ani mm. of ________, a psychosomatic gynecological disorder encountered clinically when pelvic exam is attempted. In mild forms, it causes _________ (painful intercourse); in severe forms, it prevents vaginal entry
Vaginismus; dyspareunia
