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 After examining hand is withdrawn, the distance between the tip of index finger and marked level of pubic symphysis is measured to estimate true conjugate, which should be 11 cm or greater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