Post on 17-Dec-2015
Marilyn Rose
Formed by the sacrum, coccyx and two os caxae/ innominate bones Sacrum-5 fused vertebral segments
▪ First segment▪ sacral promontory- landmark-separates abdominal
cavity/ pelvic cavity▪ The 5 segment transverse processes combine to
form the lateral mass or ala(sacral foramina= nerve passageway) articulates with the os coxae @ the sacroiliac joints
▪ The fifth segment articulates with the coxxyx (3-5) small fused bony segments.
3 bones- ilium, pubis and ishium Ilium- larges, superior-
ala- iliac fossa▪ Superior ridge of the ala=
iliac crest
▪ Slopes down to form ASIS and AIIS
▪ Body of the ilium creates the upper acetabulum, which articulates with the femoral head
Pubis- pubic bone Forms the lower
anterior acetabulum
Body, superior and inferior pubic rami
Bodies of the two pubic bones form the-symphysis pubis
Ischium- inferior os caxae Body and two rami Body- forms
lower,posterior acetabulum Sup ramus-
posterior/inferior ▪ forms ischial tuberosity
Inf ramus- anterior, medial▪ Forms ischial spine
Union of the pubic rami and ishium surrounds the obturatior foramen- obturator muscles pass
False/ Greater Pelvis Above the pelvic brim
True/Lesser Pelvis Below pelvic brim
Pelvic Inlet Superior- true pelvis- sacral
promontory to the crest of the pubic bone.
Pelvic Outlet Inferior- tip of coccyx to
inferior margin of pub symphysis or between the ischial tuberosities.
osteosarcoma of the ilium
MaleFemale
Extra-pelvic Rectus abdominis- ant abd Psoas-lat L spine External/internal oblique- lat
abdomen- ribs-iliac crest Hip muscles:
▪ Gluteus- maximus, medius, minimus- ▪ abduct, rotate, extend the thigh
Pelvic Wall Piriformis-ilium to > troch Obturator internus- pubic
bone to > troch Obturator externus Iliacus + psoas= iliopsoas
▪ To <<< troch▪ Makes walking possible!!!
Pelvic diaphragm •Majority of the pelvic floor•Levator ani- sym pub-ischial spine to coccyx•Coccygeus- posterior floor- ischial spine- coccyx
Psoas (8)
Maximus (24) and medius (25)Rectus abdominus (10)
Obturator internus/exturnus (39,40)
Ishial Tuberosity (44)
Descending AO- bifurcates at L4 into RT/LT common iliac arteries Each common bifurcates
into Internal/External iliac arteries▪ Internal iliac- smaller- supplies
O2 blood to pelvis▪ External iliac- larger- extends
along pelvic brim and exits the iliac fossa and supplies arterial blood to the leg(s)▪ External iliac becomes the femoral
artery at the ASIS! ▪ Wow! A handy landmark!!!
External iliac Common femoral
Internal iliac veins-main drainage for pelvis Superior rectal, median sacral and gonadal also are
present Ascend pelvis medial to internal iliac artery Venous plexuses drain into the internal iliac vein External iliac- extension of of femoral- return blood from
legs Medial to external iliac artery Move posteriorly as they join common iliac vein at SI joint
Common iliac vein- posterior to common iliac from the junction of int/ext iliacs
IVC at L5 right of midline- after the union of the common iliac veins
Key:
#1 = L5#2 = Ascending Colon#3 = Descending Colon#4 = Ureters (left & right)#5 = Iliac Crest#6 = Gluteus Medius#7 = Iliacus Muscle#8 = Psoas Muscle#9 = Rectus Abdominis#10 = Common Iliac Arteries#11 = Common Iliac Veins
CFA/V- #20Troch- #37Ischial spine- #35Rectum- #30Prostate-#32
Rests on pelvic floor -posterior to symphysis pubis
Neck of the bladder- internal urethral sphincter (bladder control)
Trigone= openings in the floor of the bladder- ureters and urethra Female urethra- 3-4 cm-
external opening Male urethra- 18-20 cm-
▪ Prostatic, membranous and penile urethra
▪ Dual function
Terminal portion of the large intestine S3- to tip of coccyx- 15 cm in length Anteroposterior curve (sacral flexure)
of sacrum and then ends by turning inferiorly/ anteriorly to become anal canal (perineal flexure)
Between two flexures is the transverse rectal fold- Kohlrausch’s fold- 5-8 cm from anus. Landmark for males prostate exam
and the vault of the vagina in females
Involuntary internal anal sphincter and voluntary external anal sphincter
Sex hormones, ova and protect and support a developing embryo
Uterus, ovaries, fallopian tubes, vagina Uterus-
▪ endometrium, myometrium and perimetrium
Stabilized by suspensory ligaments- ▪ Round, uterosacral and lateral cervical
ligaments Broad ligament-(peritoneal fold) -
encloses the ovaries, fallopian tubes and uterus
Two pouches- areas where fluid can accumulate▪ Vesicouterine pouch- btw ut and post wall
of bladder▪ Rectouterine pouch (pouch of Douglas)-
posterior, between uterus and rectum
Ovaries- paired on each side of uterus
Fallopian tubes- muscular tubes extending laterally form body of UT to peritoneum-supported by broad lig
Vagina- anteroinferiorly from cervix of UT to external vaginal orifice- between bladder and rectum
Organs- testis, epididymis, vas deferens, ejaculatory duct, seminal vesicle,
prostate gland, bulbourethral gland (Cowper’s) and penis All structures except testes and penis are located within pelvic
cavity. Scrotum-
pouch that encloses the testis, epididymis and lower spermatic cord- the epididymis is tightly coiled tubular structure at the superoposterior surface of each testis-composed of a head, body and tail.
Vas deferens and ejaculatory duct- Posterior spermatic cord- courses up inguinal canal and over ureter
into and into the posterior surface of the bladder- it joins with the duct of the seminal vesicle to form the ejaculatory duct which empties into the prostatic urethra
Seminal vesicles- paired glands lateral to vas deferens and on the posterior/inferior surface of the bladder-superior to the prostate
Penis- made of 3 cylindric tissues bundles- 2 corpora cavernosa and one
corpus spongiosum
1, sartorius m. 2, femoral a. 3,femoral v. 4, left pectineus m. 5, pubis 6, symphysis pubis 7, spermatic cord 8, right pectineus m. 9, obturator internus
m. 10, gemellus inferior m.
1, rectus abdominis m. 2, bladder 3, pubis 4, ischium 5, testis 6,
corpus cavernosum
1, rectus abdominis m. 2, symphysis pubis 3, corpus cavernosum 4, corpus spongiosum 5,
prostate 6, bladder 7,seminal vesicle 8, rectum 9, sacrum
Largest accessory gland of male reproductive system- secretes seminal fluid
Inferior to the bladder and surrounds the prosthetic urethra
Base- adjacent to the bladder neck
Apex- urogenital diaphragm
Two lateral lobes, middle lobe and anterior fibromuscular portion- 4 zones
Second most common cancer in men over 55
Axial T2-weighted image obtained through the midprostate
shows the prostatic urethra (P) in the posterior prostate
Normal MR imaging anatomy of the male urethra in a 59-year-old man.
prostatic urethra (P) in the posterior prostate
bulbous urethra (B) traversing the midline within the corpus spongiosum
Nodal chainsCorrespond to pelvic vessels
Obturator nodes- along midpoint of obturator internus muscle
Internal/External nodes Sacral nodes Inguinal nodes
Pelvic nodes are pathologically enlarged when they exceed 10 mm in short axis