Chapter 41 WB Anatomy and Physiology of the female pelvis

Paired triangular, flat muscles that cover the inner curved surface of the iliac fossae; arise from the iliac fossae and join the psoas major muscles to form the lateral walls of the pelvis

iliacus muscle

Pelvic cavity found below the brim of the pelvis

true pelvis

One of two muscles of the pelvic diaphragm that stretch across the floor of the pelvic cavity like a hammock, supporting the pelvic organs and surrounding the urethra, vagina, and rectum; a broad, thin muscle that consists of the pubococcygeus, iliococcygeus, and puborectalis muscles.

levator ani

one of two muscles in the pelvic diaphragm located on the posterior pelvic floor where it supports the coccyx

coccygeus muscles

A flat pyramidal muscle arising from the anterior sacrum, passing through the greater sciatic notch insert into the superior aspect of the greater trochanter of the fumur; serves to rotate and abduct the thigh.

piriformis muscle

parallel longitudinal lines commonly seen in muscle tissue when imaged sonographically; appear as hyperechoic parallel lines running in the long axis of the hypoechoic muscle tissue

striations

A bony ridge on the inner surface of the ilium and pubic bones that divides the true and false pelvis.

iliopectineal line

Paired muscle that originates at the transverse process of the lumbar vertebrae and extends inferiorly through the false pelvis on the pelvic sidewall, where it unites with the iliacus muscle to form the iliopsoas muscle before inserting into the lesser trochanter of the femur; serves to flex the thigh toward the pelvis

psoas major muscle

Portion of the pelvis found above the brim; that portion of the abdominal cavity cradled by the iliac fossae

false pelvis

A triangular sheet of muscle that arises from the anterolateral pelvic wall and surrounds the obturator foramen; passes through the lesser sciatic foramen and inserts into the medial aspect of the greater trochanter of the femur; serves to rotate and abduct the thigh

obturator internus muscle

Position of the uterus when the entire uterus is tipped posteriorly so that the angle formed between the cervix and the vaginal canal is greater than 90 degrees

retroverted

steroidal hormone secreted by the theca interna and granulosa cells of the ovarian follicle that stimulates the development of the female reproductive structures and secondary sexual characteristics; promotes the growth of endometrial tissue during the proliferative phase of the menstrual cycle.

estrogen

female egg; secondary oocyte released from the ovary at ovulation

ovum

Wide band of fibromuscular tissue arising from the lateral aspects of the cervix and inserting along the lateral pelvic floor; a continuation of the broad ligament that provides rigid support for the cervix

cardinal ligament

Posterior portion of the broad ligament that is drawn out to enclose and hold the ovary in place.

mesovarium

Position of the uterus when the uterine fundus bends forward toward the cervix

anteflexed

Paired ligaments that extend from the infundibulum of the fallopian tube and the lateral aspect of the ovary to the lateral pelvic bone

suspensory ligament

Area in the pelvic cavity between the rectum and the uterus where free fluid may accumulate

rectouterine recess (pouch)

broad fold of peritoneum draped over the fallopian tubes, uterus, and ovaries. extends from the sides of uterus to the sidewalls of the pelvis, dividing the pelvis from side to side and creating the vesicouterine pouch anterior to the uterus and rectouterine pouch posteriorly, divided into the mesometrium, mesosalpinx, and mesovarium.

broad ligament

upper portion of the broad ligament that encloses the fallopian tubes

mesosalpinx

area in the pelvic cavity between the urinary bladder and the uterus

vesicouterine recess (pouch)

serous membrane enveloping the uterus

perimetrium

located between the anterior bladder wall and the pubic symphysis contains extraperitoneal fat.

space of retzius

Positon of the uterus when the uterus is tipped slightly forward, so that the cervix forms a 90 degree angle or less with vaginal canal

anteverted

Position of the uterus when the uterine fundus bends posteriorly upon the cervix

retroflexed

Paired ligaments that originate at the uterine cornua, anterior to the fallopian tubes, and coats anterolaterally within the broad ligament to insert into the fascia of the labia majora, hold the uterus forward in its anteverted position.

round ligament

steroidal hormone produced by the corpus luteum that helps prepare and maintain the endometrium for arrival and implantation of an embryo

progesterone

paired ligament that extends from the inferior and/or medial pole of the ovary to the uterine cornua.

ovarian ligament

posterior portion of the cardinal ligament that extends from the cervix to the sacrum

uterosacral ligament

anatomic structure on the surface of the ovary, consisting of a spheroid of yellowish tissue that grows within the ruptured ovarian follicle after ovulation acts as a short lived endocrine organ that secretes progesterone to maintain the decidual of the endometrium should conception occur

corpus luteum

Hormones secreted by the hypothalamus that stimulates the release of FSH and lutenizing hormone by the anterior pituitary gland

gonadotropin releasing hormone

hormone secreted by the anterior pituitary gland that stimulates the growth and maturation of graafian follicles in the ovary

FSH

abnormally heavy or long menstrual periods

menorrhagia

absense of menstruation

amenorrhea

refers to cessation of menstruation

menopause

abnormally light menstrual periods

oligomenorrhea

pain associated with menstruation

dysmenorrhea

refers to the onset of menstruation and the commencement of cyclic menstrual function usually occurs between 11 and 13 years of age

menarche

hormonal substance that stimulates the function of the testes and ovaries

gonadotropin

periodic flow of blood in cellular debris

menses

time period in young girls before the onset of menstruation

premenarche

hormone secreted by the anterior pituitary gland that stimulates the ovulation and then induces lutenization of the ruptured follicle to form the corpus luteum

luteinizing hormone

The anterior cul-de-sac, or _________ pouch, is located anterior to the fundus of the uterus between the urinary bladder and the uterus.

vesicouterine

The posterior cul-de-sac, or _____________ pouch, is located posterior to the uterus between the uterus and the rectum.

rectouterine

The rectouterine pouch is often referred to as the pouch of ________ and is normally the most inferior and most posterior region of the peritoneal cavity.

douglas

An additional sonographically significant area is the retropubic space, which is also called the space of __________ .

retzius

The retropubic space normally can be identified between the __________ bladder wall and the pubic symphysis.

anterior

The retropubic space normally contains subcutaneous fat, but a hematoma or abscess in this location may displace the urinary bladder ____________ .

posteriorly

The greatest quantity of free fluid in the cul-de-sac normally occurs immediately following __________ when the mature follicle ruptures.

ovulation

The average menstrual cycle is approximately _______ days in length, beginning with the first day of menstrual bleeding

28

The menstrual cycle is regulated by the ___________ and is dependent upon the cyclic release of estrogen and progesterone from the ovaries.

hypothalamus

During the menarchal years, a(n) _____ is released once a month by one of the two ovaries in a process known as ovulation.

ovum

Ovulation normally occurs midcycle on about day ____ of the 28 day cycle.

14

Secretion of the ____ by the anterior pituitary gland causes the ovarian follicles to develop during the first half of the menstrual cycle

FSH

This phase of the ovulatory cycle, known as the _____ phase, begins with the first day of menstrual bleeding and continues until ovulation on day 14.

follicular

The ___________ hormone level will typically increase rapidly 24-36 hours before ovulation in a process known as the LH surge.

luteinizing

Cells in the lining of the ruptured ovarian follical begin to multiply and create the corpus luteum, or yellow body during the______phase

luteal

The phase of endometrial regeneration is called the ___________ phase and will last until luteinization of the graafian follicle around ovulation

proliferative

The endometrial phase after ovulation is referred to as the _________ phase and extends from approximately day 15 to the onset of menses (day 28). the secretory phase of the endometrial cycle corresponds to the luteal phase of the ovarian cycle

Secretory

The transabdominal scan offers a(n) ______________ field of view for a general screening of the pelvic anatomy.

wider

The ___________ are folds of skin at the opening of the vagina; the labia _________ is the thicker external folds, and the ________ consists of thin folds of skin between the labia majora

labia; majora; minora

The ___________ bones make up the anterior and lateral margins of the bony pelvis; the ______ and ______ form the posterior wall.

innominate; sacrum; coccyx

The margins of the posterolateral wall of the true pelvis are formed by the _________ and _________ muscles

piriformis; coccygeus

The anterolateral walls of the pelvic cavity are formed by the hip bones and the ______________ muscles that rim the ischium and pubis

obturator internus

The lower margin of the pelvic cavity. the pelvic floor, is formed by the ___________ and ____________ muscles and is known as the pelvic diaphragm.

levator ani; coccygeus

The area below the pelvic floor is the ___________.

perineum

The muscles of the false pelvis include the _________ major and ___________ muscles

psoas; iliacus

The muscles that arise from the lower part of the pubic symphysis and surrounded the lower part of the rectum , forming a sling are the ______________ muscles

puborectalis

A collapsed muscular tube that extends from the external genitilia to the cervix of the uterus is the __________.

vagina

The cervix lies _______________ to the urinary bladder and the urethra and ___________ to the rectum and anus

posterior; anterior

The largest organ in the normal female pelvis when the urinary bladder is empty is the ___________.

uterus

At the lateral borders of the uterine fundus are the _______, where the fallopian tubes enter the uterine cavity.

cornua

The cervix is constricted at its upper end by the _______ os and at its lower end by the ________ os.

internal; external

The point where the uterus bends anteriorly (anteversion) or posteriorly (retroversion) with an empty bladder is the _____________.

isthmus

The uterine wall consists of three histologic layers: the ________ , the _________, and the ___________.

perimetrium; myometrium; endometrium

The endometrium consists primarily of two layers: the superficial functional layer (zona ___________) and the deep basal layer (zona ________).

functionalis; basalis

The uterus is supported in its position by paired ________ ligaments, ___________ ligaments, _____________ ligaments, and __________ ligaments.

broad; round; uterosacral; cardinal

The average uterine position is considered to be _____________ and _____________.

anteverted; anteflexed

The _____________ are contained in the upper margin of the broad ligament and extend from the uterine cornua of the uterus laterally where they curve over the ovary.

fallopian tubes

The fallopian tubes are divided into four anatomic portions: the ____________ (lateral segment), ___________ (middle segment), ___________ (medial segment), and _________ portions (segment that passes through the uterine cornua)

infundibulum; ampulla; isthmus; interstitial

The __________ is often referred to as the fimbriated end of the fallopian tube because it contains fringe like extensions, called fimbriae, which move over the ovary, directing the ovum into the fallopian tube after ovulation

infundibulum

The ovaries are usually located __________ to the external iliac vessels and ____________ to the internal iliac vessels and ureter

medial; anterior

The cortex of the ovary consists primarily of follicles in varying stages of development and is covered by a layer of dense connective tissue, the __________________.

tunica albuginea

The central __________ is composed of connective tissue containing blood, nerves, lymphatic vessels, and some smooth muscle at the region of the hilum.

medulla

The ovaries produce the reproductive cell, the ovum, and two known hormones: ________, secreted by follicles, and __________, secreted by the corpus luteum.

estrogen; progesterone

The common ___________ arteries course anteriorly and medially to the psoas muscles, providing blood to the pelvic cavity and lower extremities

iliac

The __________ iliac arteries extend into the pelvic cavity along the posterior wall and provide multiple branches that perfuse the pelvic structures to include the urinary bladder, uterus, vagina, and rectum.

internal

The ________ arteries extend through the myometrium to the base of the endometrium, where straight and spiral arteries branch off the radial arteries to supply the zona basalis of the endometrium.

radial

The _________ arteries will lengthen during regeneration of the endometrium after menses to transverse the endometrium and supply the zona functionalis.

spiral

The approach that requires a full urinary bladder for use as an "acoustic window" and typically necessities the use of a 3.5-5 MHz transducer for adequate penetration is the ____________ approach.

transabdominal

A(n) ____________ examination is performed with an empty bladder and allows the use of a higher-frequency transducer, typically 7.5-10 MHz

transvaginal