Anatomy Exam 3: Pelvis/Reproductive

What is the function of the pelvic girdle?

transfer weight of upper body from axial skeleton to appendicular skeleton; supporting body weight

Bony pelvis is composed of:

ilium, ischium, pubis, sacrum and coccyx

posterior part of the pelvic girdle

sacrum at the sacro-iliac joints

superior boundary of the pelvic cavity

pelvic inlet

inferior boundary of the pelvic cavity

pelvic outlet

anterior boundary of the pelvic cavity

pubic symphysis

posterior boundary of the pelvic cavity

sacrum & coccyx

subpubic angle in females

wider; 70-90 degrees

subpubic angle in males

narrower; 50-60 degrees

what makes up the anteroinferior pelvic wall and its role

rami of pubic bones, pubic symphysis

-bear weight of urinary bladder

how many lateral pelvic walls are there?

2

what makes up the lateral pelvic wall

hip bones (ilium, pubis, ischium) and obturator foramen

obturator interns m. function

provides attachment for elevator ani or pelvic diaphragm

muscles of the pelvic wall and floor

levator ani muscles, coccygeus m., piriformis m.

muscles of the elevator ani group

puborectalis m., pubococcygeus m., iliococcygeus m.

What is the most important of the pelvic floor muscles?

levator ani muscle group

(puborectalis, pubococcygeus, iliococcygeus)

sciatic nerve and location

lumbar plexus and sacral plexus (L4-S3)

passes inferior to piriformis m

sacral plexus nerves

pudenal, superior gluteal nerve, inferior gluteal nerve

pudenal nerve location

(S2-S4); between piriformis and coccygeus muscles

pudenal nerve

main nerve of the perineum; chief sensory nerve of the external. genitalia; innervates urethral sphincter

superior gluteal n.

L4-S1; supplies glut. medius and minimus

inferior gluteal n.

L5-S2; supplies glute. maximus

Obturator nerve

primary nerve to medial thigh; (L2-L4); passes through pelvis

What nerve is vulnerable to injury during surgery along the pelvic wall?

Obturator nerve

Where does is the terminal bifurcation of the abdominal aorta?

(L4) —> common iliac a.

2-3 cm inferior and to the left of the umbilicus

What are the branches of the common iliac a?

internal iliac a. & external iliac a.

What is made up of two triangle-shaped areas?

Perineum; (anal & urogenital triangles)

Anterior triangle (UG)

pubic (anteriorly) symphysis to the ischial tuberosities (laterally)

Posterior triangle (anal)

ischial tuberosities (lateral) to the sacrum/coccyx (posterior)

Testes

produce sperm

each testis is divided into 250 lobules; each lobule contains coiled seminiferous tubules

Epididymis

storage of sperm

posterior, superior, and lateral to testes

-made up of head, body, tail

Seminal vesicle

produces energy source and enzymes for sperm

paired and attach to the ejaculatory duct, near the base of the bladder posteriorly

recreate alkaline fluid to regulate pH

Prostate Gland

produces milky fluid that enhances the motility of the sperm cells and neutralizes the vagina’s acidic secretions

-secretion contains PSA

Location of the prostate gland

surrounds the proximal portion of the urethra, inferior to the bladder

Cowper’s Glands (bulbourethral)

glands increase mobility of sperm

inferior to the prostate gland

secrete mucus-like fluid (pre-ejaculate)

The seminiferous tubules are made up of …

spermatogenic cells and interstitial cells (cells of Leydig)

role of the cells of Leydig

produce and secrete male sex hormones

Spermatogenesis steps

sperm production, sperm migration, maturation/storage

order of sperm migration

Sertoli cells → rete testis → efferent ductules → epididymis

Vas Deferens

connects epididymis to ejaculatory duct

-passes through the inguinal canal & joins with seminal vesicles to form ejaculatory duct

-Function: movement of sperm

spermatic cord

from testicle to abdomen-inguinal ring

Constituents: spermatic vein, spermatic artery, vas deferens, lymphatics, nerves (ilioinguinal and genitofemoral)

scrotum

function: support and protect testes

structures: cremaster m. —> involuntary contraction in response stimuli, scrotal raphe

Penis

urethra extends through the corpus spongiosum

function: convey urine/semen through urethra

-has prepuce(foreskin), paired corpora cavernosa (dorsally), single corpus spongiosum (ventrally)

Parts of the uterus (fundus, body, cervix)

endometrium, myometrium, cervical canal, cervix, Os

Uterine ligaments

broad, round, ovarian, suspensory

Broad ligament

(uterus to pelvis) holds the ovaries and uterine tubes

round ligament

(uterus to labia majora) passes through the inguinal canal

ovarian ligament

attaches ovary to the superior margin of the uterus

suspensory ligament

extends from the mesovarium to the body wall

ovaries

lie in shallow depressions in the lateral pelvic cavity wall

Uterine wall is thick and made up of

3 layers, endo, myo, peri

endometrium

inner mucosal layer, hormone sensitive

sheds during menstrual phase

myometrium

thick muscular layer, distended in pregnancy

perimetrium

outside layer covering the body of the uterus

Vagina

extends from the uterus/cervix to outside of the body

conveys uterine secretions

hymen

thin membrane covering the vaginal opening

Fornices

junction with cervix of uterus with vagina

posterior fornix is deepest part

External female reproductive organs

accessory: Mons pubis, labia majora, labia minora, clitoris, vestibular glands (Bartholin)

Quadrants of the breast

superomedial, Inferomedial, inferolateral, superolateral

tail of spence

axillary tail (superolateral quadrant)

Breast location

2nd -6/7th ribs; lateral border of sternum to midaxillary line

-nipple located at 4th intercostal space

Blood supply of breast

subclavian artery, subclavian vein

lymph drainage of breast

supraclavicular, infraclavicular, centeral humeral, subscapular, pectoral