Pelvis And Perineum

Front 1

sexual differences in bony pelvis p. 209

Back 1

men: funnel shaped, heavier, larger, thicker and has more prominent bone markings to compensate for hevier/larger musc. of men

female: rounded, oval shape with wide transverse diameter. also shallower, and has wider pelvic outlet/inlet. the shape and size of the pelvic inlet are significant because it is through this opening that the fetal head enters the lesser pelvis during labor. -

to determine the capacity of the pelvis for childbirth, the diameter of the lesser pelvis are noted during pelvic exams.

ischial spines = face each other and the interspinous distance b/w them is the narrowest part of the pelvic canal - through which the baby's head must pass

Front 2

pelvic fractures p. 209

Back 2

crush accidents --> fractures of pubic rami, acetabulum, and ala of ilium

usually multiple fractures combined with a joint dislocation

often effects all of the nerves, arteries and muscles closely surrounding the fracture

Front 3

pelvic relaxation and increased joint mobility during preg. p. 211

Back 3

during preg. joints/ligaments relax and pelvic movements increase.

relaxation attempts to learn how to relax muscles of the pelvic floor voluntarily while increasing intra-abdominal pressure (natural response is to contract during pressure)

occurs during latter half of preg. caused by increased levels of sex hormones and hormone relaxin.

facilitates passage of fetus through birth canal providing decreasing resistance during uterine contractions

relaxation by rotation of pelvis contributes to lordotic posture

Front 4

injury to the pelvic floor p. 217

Back 4

perineum, levator ani, and pelvic fascia may be injured during childbirth (pubococcygeus which is part of the levator ani is most often torn) --> this weakening may cause change in position of bladder and urethra. this results in urinary stress incontinence (dribbling of urine when intra-abdominal pressure is increased)

Front 5

injury to pelvic nerves p. 218

Back 5

sacral plexus --> compression by baby’s head during childbirth, produces pain in her lower limbs.

obturator nerve --> vulnerable during surgical procedure along pelvic wall

injury of the obturator nerve may cause painful spasms of the adductor musc. of the thigh and sensory deficits in the medial thigh region.

Front 6

ureteric calculi p. 225

Back 6

aka kidney stones

pain caused by larger stones = colicky pain from hyperperistalsis superior to level of obstruction
may cause complete or intermittent obstruction of urinary flow

most often occurs at 3 sites
1) junction of ureters and renal pelvis
2)where they cross the external iliac artery and the pelvic brim
3)junction at urinary bladder

removed through surgery, endoscopy, or lithotripsy (shock waves break up stone into fragments)

Front 7

suprapubic cystotomy p. 228

Back 7

distended bladder lies adjacent to anterior abdominal wall and above the pubic symphysis

distended bladder is punctured (suprapubic cystotomy) or can be approached with in-dwelling catheter or other instruments for removal of calculi or foreign bodies without entering the peritoneal cavity

Front 8

cystoscopy p. 229

Back 8

examination of interior of the bladder and its 3 orifices

used for tumor removal (transurethral resection of a tumor)

Front 9

rupture of bladder p. 228

Back 9

injury to inferior part of abdominal wall or pelvic fractures may rupture distended bladder

superior rupture often tears peritoneum, resulting in extravasation of urine into the peritoneal cavity

posterior rupture --> urine into perineum

Front 10

sterilization of males aka deferentectomy/vasectomy p. 233

Back 10

part of vas deferens is ligated and or excised through incision in the superior part of the scrotum

ejaculated fluid from the seminal glands, prostate, and bulbourethral glands have ho sperms.*

unexpelled sperms degenerate in the epididymis and the proximal part of the ductus deferens

reversal is often successful in younger men and short post-op delays

Front 11

prostatic enlargement p. 235

Back 11

BHP (benign hypertrophy of prostate) = common after middle age. it impedes urination by distortion of prostatic urethra. the middle lobule usually enlarges the most and obstructs the internal urethral orifice.

Can cause nocturia (voiding at night), dysuria (pain during urination), and urgency
Examined through a digital rectal exam

Front 12

prostatic cancer and prostotectomy p. 235

Back 12

common in men older than 55 years

most cancer develops in the posterolateral region.

this may be palpated during a digital rectal exam.

a malignant prostate feels hard and often irregular - in advanced stages, it spreads to internal iliac and sacral lymph nodes, and later to distant lymphs and bones.

the prostatic plexus, closely associated with the prostatic sheath, gives passage to parasympathetic fibers, which give rise to the cavernous nerves that convey the fibers that cause penile erection

for prostatectomy, impotency may be a consequence. all or part of the prostate or just the hypertrophied part is removed (TURP - transurethral resection of the prostate). removal of the seminal glands, performed for serious cases

Front 13

distention and examination of vagina p. 238

Back 13

can be distended in an anteroposterior direction. lateral distension is limited by the ischial spines. distended using vaginal speculum

when distended, usually in region of the posterior fornix--> allows palpation (in the vagina or rectum) of cervix, ischial spine, and sacral promontory and also occurs during intercourse

especially distended during parturition (in AP direction)

palpation of sacral promontory, irregularities in ovaries (cysts), and pulsations of uterine arteries

Front 14

culdocentesis p. 238

Back 14

inserted through posterior part of vaginal fornix into the peritoneal cavity to drain a pelvic abscess in the recto-uterine pouch. fluid in this part of the perineal cavity (eg. blood) can be aspirated at this site.

in addition culdoscopy is performed in order to examine ovaries or Fallopian tubes (to assess a tubal pregnancy)

Front 15

hysterectomy p. 242

Back 15

excision of the uterus - performed through the lower anterior abdd. wall or
through the vagina

in danger of accidentally clamping or severing the ureter - which is posterior to the uterine artery near the lateral fornix of the vagina

done in response to uterine and cervical cancer

Front 16

cervical exam and pap smear p. 242

Back 16

distended with vaginal speculum
to inspect cervix.

a spatula is placed on the external os of the uterus. the spatula is rotated to scrape cellular material from the vaginal surface of the cervix, followed by insertion of a cysto-brush into the cervical canal that is used to gather cellular material from the supravaginal cervical mucosa.
- cells are examined under microscope


Pap smears have decreased the incidence of cervical cancer by detection of premalignant conditions

Front 17

laparoscopic exam of pelvic viscera p. 249

Back 17

involves inserting a laparoscope into the peritoneal cavity through a small incision below the umbilicus

insufflation of inert gas creates a pneumoperitoneum to provide space to visualize the pelvic organs.

laparoscopic tubal ligation = laparoscope is inserted through a small incision, usually near the umbilicus

for diagnosis of ovarian cysts, tumors, endometriosis

Front 18

caudal epidural block p. 243

Back 18

lumbar epidural and low spinal blocks anesthetize somatic and visceral afferent fibers distributed below waist level, anesthetizing the uterus, entire birth canal, and peritoneum, but also the lower libs.

*caudal epidural block is a pop. choice for participatory childbirth it must be administered in advance of childbirth.
administered using an indwelling catheter in the sacral canal for a deeper or prolonged anesthesia.
S2-S4 spinal nerves, including the visceral pain fibers from the uterine cervix and upper vagina, and somatic pain fibers of the pudendal nerve are the nerves affected (not including lower limbs for caudal epidural- just the birth canal)

nerves of the uterine fundus are also not affected and sensations of uterine contraction are still perceived.

pudendal nerve blocks and local infiltration of the perineum provide only somatic anesthesia of the perineum

Front 19

infections of female genital tract p. 247

Back 19

infections of the vagina, uterus, and uterine tubes may result in peritonitis* since the female genital tract communicates with the peritoneal cavity through the abd. ostia of the uterine tubes

inflammation of the tubes (salpingitis) may result from infections that spread from the peritoneal cavity.

a major cause of infertility in women is blockage of the uterine tubes, often the result of infection that causes salpingitis.

Front 20

patency of uterine tubes p. 247

Back 20

hysterosalpingography- patency determined by radiographic procedure involving injec. of dye or CO2 gas into the uterus and tubes

hysteroscopy - exam of interior of tubes, through vagina and uterus

Front 21

ligation of uterine tubes p. 249

Back 21

surgical method of birth control (oocytes degenerate and are absorbed)

abdominal tubal ligation is usually performed through a short suprapubic incision made just at the pubic hairline

laparoscopic tubal ligation is done with a laparoscope. it is inserted through a small incision, usually near the umbilicus.

Front 22

ectopic tubal pregnancy p. 249

Back 22

blastocyst fails to reach the uterus and implant in the mucosa of the uterine tube.

most common site = ampulla of uterine tube


on the right side, the appendix often lies close to the ovary and uterine tube. this close relationship explains why ruptured tubal pregnancy and the resulting peritonitis may be misdiagnose as acute appendicitis.

in both cases, the parietal peritoneum is inflamed in the same general area and the pain is referred to the RLQ of the abdomen.

rupture can result in severe hemorrhage.

Front 23

rectal exam p. 249

Back 23

prostate / seminal glands and cervix can be palpated through its walls

the pelvic surfaces of the sacrum and coccyx may be palpated in both sexes.

palpation of ischial spines, enlarged lymph nodes, pathologic thickening of the ureters, swellings of ischioanal fossae (abscesses and abnormal contents in the rectovesical pouch in male and recto-uterine pouch in female)

tenderness of an inflamed appendix may also be detected rectally if it descends into the lesser pelvis (pararectal fossa)

proctoscope / sigmoidoscope = visualize internal aspect of rectum and must be careful to go around transverse rectal folds

Front 24

disruption of perineal body p. 253

Back 24

perineal body is the final support of the pelvic viscera. stretching or tearing of this attachment of the perineal muscles from the perineal body can occur during childbirth, removing support provided by the pelvic floor. as a result, prolapse of pelvic viscera, including prolapse of the bladder and prolapse of the uterus and/or vagina may occur.

Front 25

episiotomy p. 253

Back 25

surgical incision of the perineum and inferoposterior vaginal wall to enlarge the vaginal orifice with intention of decreasing excessive tearing of the perineum and perineal musc.

performed in large portion of vaginal deliveries

done when descent of the fetus is arrested of protracted, when isntrumentation is necessary, or to expedite delivery when there are signs of fetal distress. decreases trauma to the pelvic diaphragm

median episiotomies can result in tearing down to the anus and incontinence and pelvic prolapse

mediolateral episiotomies = better alternative, directing tearing away from the anus and perineal body

Front 26

rupture of urethra in males and extravasation of urine p. 256

Back 26

rupture of the intermediate part of the urethra = caused by fractures of pelvic girdle. this results in 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.

rupture of the spongy urethra = results in urine passing (extravasating) into the superficial perineal space.

the attachments of the perineal fascia determine the direction of flow of the extravasated urine.

urine and blood may also pass into the scrotum. it cannot pass far into the thighs due to fascia lata

urine also cannot pass posteriorly into the anal triangle. it will be contained within perineal pouches due to perineal membrane

Front 27

ischio-anal abscesses p. 258

Back 27

occasional sites of infection, which may result in the formation of ischioanal abscesses.

extremely painful.

diagnostic signs are fullness and tenderness b/w the anus and the ischial tuberosity

a perianal abscess may rupture spontaneously, opening into the anal canal, rectum, and perianal skin

Front 28

hemorrhoids p. 260

Back 28

internal "piles"-- bright red because of internal rectal venous plexus

result from breakdown of muscularis mucosa, a smooth musc. layer deep to the mucosa.

are often compressed by the contracted sphincters, impeding blood flow, so they tend to strangulate and ulcerate.

external --> thromboses in external veins of external rectal venous plexus covered by skin.

pregnancy, chronic constipation, prolonged toilet sitting, and any disorder that impedes venous return, including increased intra-abdominal pressure.

can also be caused by portal hypertension and portocaval anastomoses, but most commonly occur without it
superior to pectinate line -- internal hemorrhoids are not painful (visceral pain)
inferior to pectinate line -- external hemorrhoids are more painful (somatic pain)

Front 29

urethral catheterization p. 261

Back 29

done to remove the urine from a person who is unable to micturate.

also performed to irrigate the bladder and to obtain an uncontaminated sample of urine.

when inserting the catheters and urethral sounds (for exploring and dilating a constricted urethra) the curves of the male urethra must be considered.

Front 30

erection, emission, ejaculation, and remission p. 265

Back 30

erection = occurs as the corpora cavernosa and corpus spongiosum becomes engorged with blood at arterial pressure, causing the erectile bodies to become turgid (enlarged and rigid), elevating the penis

emission = semen is delivered to the prostatic urethra through the ejaculatory ducts after peristalsis of the ductus deferentes and seminal glands. prostatic fluid is added to teh seminal fluid as the smooth musc. in the prostate contracts.

ejaculation = semen is expelled from the urethra through the external urethral orifice

remission = the penis gradually returns to a flaccid state, resulting from sympathetic stimulation that opens the arteriovenous anastomoses and causes contraction of smooth musc. --> blood flow is reduced as bulbospongiosus and ischiocavernosus relax, allowing more blood to drain into the deep dorsal vein.

Front 31

dilation of female urethra p. 270

Back 31

the female urethra is distensible because it contains considerable elastic tissue, as well as smooth musc.

it can easily dilate without injury to it. consequently, the passage of catheters or cyctoscopes in females is much easier than it is in males.

Front 32

inflammation of greater vestibular glands p. 270

Back 32

aka Bartholin glands = not usually palpable, except when infected

Bartholinitis = inflammation of the glands resulting from occlusion of gland ducts or pathogenic organisms

can impinge on the wall of the rectum

Front 33

pudendal nerve block and ilio-inguinal nerve block p. 270

Back 33

performed by injecting a local anesthetic agent into the tissues surrounding the pudendal nerve.

the injection may be made where the pudendal nerve crosses the lateral aspect of the sacrospinous ligament, near its attachment to the ischial spine.

anesthetize most of the perinem, however it does not abolish sensation from the anterior part of the perineum that is innervated by the ilio-inguinal nerve.

to abolish pain from the anterior part of the perineum, and ilio-inguinal nerve block is performed

Front 34

referred pain

Back 34

Pain is an unpleasant sensation associated with actual or potential tissue damage and mediated by specific nerve fibers to the brain, where its conscious appreciation may be modified.

Pain that is felt in a part of the body at a distance from the area of pathology, e.g., pain in the right shoulder derived from the presence of a gallstone in the bladder, or pain in the left arm and shoulder derived from the presence angina or myocardial ischemia or pain in the spine between the shoulder blades due to stomach problems, etc; the distant location often represents a parallel path within a nerve for visceral and somatic senses including pain.

Organic pain arising from an organ such as the stomach varies from dull to severe; however, the pain is poorly localized. It radiates to the dermatome level, which receives visceral afferent fibers from the organ concerned. Visceral referred pain from a gastric ulcer, for example, is referred to the epigastric region because the stomach is supplied by pain afferents that reach the T7 and T8 spinal sensory ganglia and spinal cord segments through the greater splanchnic nerve The brain interprets the pain as though the irritation occurred in the skin of the epigastric region, which is also supplied by the same sensory ganglia and spinal cord segments.

Pain arising from the parietal peritoneum is of the somatic type and is usually severe. The site of its origin can be localized. The anatomical basis for this localization of pain is that the parietal peritoneum is supplied by somatic sensory fibers through thoracic nerves, whereas a viscus such as the appendix is supplied by visceral afferent fibers in the lesser splanchnic nerve. Inflamed parietal peritoneum is extremely sensitive to stretching. When digital pressure is applied to the anterolateral abdominal wall over the site of inflammation, the parietal peritoneum is stretched. When the fingers are suddenly removed, extreme localized pain is usually felt, known as rebound tenderness.

Front 35

peritoneal reflections in the pelvis

Back 35

p. 212

Front 36

pelvic diaphragm

Back 36

The pelvic diaphragm separates the pelvic cavity from the perineum within the lesser pelvis.

components of the pelvic diaphragm (levator ani and coccygeus) form the floor of the pelvic cavity and the roof of the perineum

Front 37

sacral plexus

Back 37