Pelvis Structure & Compartmentalization: Pelvis (Dang)

What is relaxin? Can this be bad?

A hormone secreted by the placenta during pregnancy that relaxes the pubic ligaments and increases the flexibility of the symphysis -yes, relaxin post-partum will lead to other bones relaxing like feet, so women will have enlarged feet

Which landmarks of the pelvic girdle are in the same Coronal Plane? How is this possible?

ASIS and Pubic tubercle are aligned on the coronal plane How? Pelvis is tilted 55 degrees anteriorly from sitting on ischial tuberosities and coccyx

What are the different Obstetric measurements you can use to measure whether or not the birth canal will be large enough for vaginal delivery (3)? Where are they on the pelvis? -Anatomical Conjugates

Anatomical conjugate: all from sacral promontory to different portions of pubic symphysis -True Conjugate - sacral promontory to top of pubic symphysis -Obstetric conjugate - sacral promontory to middle of pubic symphysis -Diagonal conjugate - sacral promontory to bottom of pubic symphysis **Dr. Dang noted we don't need to know exact measurements, just where stuff is

What are the different birth canal shapes? (4)

Android: heart shaped; sacral promontory protrudes into pelvic inlet Gynecoid: round; capacious inlet in AP and ML diameters Anthropoid: anteroposteriorly oval inlet Platypelloid: mediolaterally oval inlet

What vessels go thru the deep inguinal ring in males?

Ductus deferens, testicular a. & v.

What cartilage makes up the pubic symphysis and where do the fibers insert?

Fibrocartilage Pubic ligaments (anterior, posterior, superior, inferior) attach to pubis and insert onto *symphyseal disc*

What are the three parts of the Linea Terminalis?

From posterior to anterior: Arcuate Line Pecten Pubis Pubic Crest

What do the fibers of the pubococcygeus do?

Help maintain and support the prostate(males) or vagina(females) -Pubostaticus(males) -Pubovaginalis(females)

What are the different Obstetric measurements you can use to measure whether or not the birth canal will be large enough for vaginal delivery (2)? Where are they on the pelvis? -Inlet

INLET -Transverse inlet - widest part along arcuate line -Oblique inlet - sacral ala to iliopubic eminence **Dr. Dang noted we don't need to know exact measurements, just where stuff is

In humans, the largest diameters of the inlet and outlet are offset by _______ degrees Therefore, the neonatal head and shoulders usually must ________ in the birth canal

In humans, the largest diameters of the inlet and outlet are offset by 90 degrees Therefore, the neonatal head and shoulders usually must rotate in the birth canal

Two muscles cover the Obturator Foramen. What are they?

Inside - Obturator Internus Outside - Obturator Externus

What lies within the hypogastric sheath? (2)

Internal iliac artery and vein

What are the two bony prominences of the ISCHIUM?

Ischial Spine Ischial Tuberosity

What are the different Obstetric measurements you can use to measure whether or not the birth canal will be large enough for vaginal delivery (3)? Where are they on the pelvis? -Outlet

OUTLET -Transverse outlet - between ischial tuberosity -Interspinous - between ischial spines -Anteroposterior outlet - pubic symphysis to sacrum **Dr. Dang noted we don't need to know exact measurements, just where stuff is

The perineal membrane is below the:

Pelvic diaphragm

Pelvic diaphragm forms boundary between the ____________ and ___________

Pelvic diaphragm forms boundary between the pelvic cavity and perineum

Why are female pelvises wider and more circular?

Provides a larger and rounder birth canal

Which space in females is the most inferior space to collect fluid from the peritoneal cavity?

Rectouterine pouch

What two bones make up the pelvic girlde?

Sacrum and the two Os Coxae

Describe the female pelvis

Sacrum: Wider and Shorter Subpubic angle: 80-90 degrees(more obtuse) Greater sciatic notch: 60 degrees(more obtuse)

Describe the male pelvis:

Sacrum: narrower and longer Subpubic angle: 50-70 degrees Grater sciatic notch: 30 degrees

Where is the peritoneum?

The peritoneum extends down from the abdominal cavity. This covering can be seen above the pelvic cavity

True/False: Anterior part or sacroiliac joint is synovial

True, functions as a keystone

Where are the ovarian a. & v found?

in the *suspensory lig. of the ovary*

What joints/articulations can be seen on the anterior view of the pelvic girdle? (3)

-Anterior lingitudinal ligament -Iliolumbar ligament -Anterior sacroiliac ligament

What is the function of the levator ani m?

-Elevates the anus

How are the false and true pelvis different?

-False pelvis: greater pelvis , above thepelvic inlet, surrounds abdominal organs -True pelvis: Lesser pelvis, below pelvic inlet, surrounds pelvic organs

What structures are contained within the cardinal/transverse cervical ligament in females (2) and Rectovesical septum in males(2)?

-Females: Uterine artery and vein -Males: Inferior vesical artery and vein

How is birth different between chimpanzee's and humans?

-Humans experience rotational birth while chimpanzee's say yeet and push tha bih straight out

What fibers make up levator ani m?

-Iliococcygeus: Ileum to coccygeal bone -Pubococcygeus: Pubic bone to coccygeal -Puborectalis: Pubic bone to rectum

Where does the membranous fascia end in males and females?

-In males: ends at puboprostatic ligament -In females: ends at pubovesical ligament

What are the boundaries of the pelvic girdle/outlet?

-Inferior pubic symphysis -ischiopubic rami -Ischial tuberosities -Sacrotuberous ligament -Coccyx

What are the two muscle groups which form the pelvic diaphragm?

-Ischiococcygeus -Levator ani 1. iliococcygeus 2. Pubococcygeus 3. Puborectalis

The pelvic diaphragm is made up of which muscles?

-Ischiococcygeus(between ischial spine and coccygeal bone) -Levator ani m: Iliococcygeus, pubococcygeus, puborectalis

What are the structure that make up the Endopelvic fascia? (4)

-Lateral ligament of the bladder -Cardinal/transverse cervical ligament (females) ; Rectovesical septum (males) -Hypogastric sheath -Lateral ligament of rectum

If you were to look inferiorly at the viscera in the pelvic cavity of males you'd see

-Lateral, medial, and median epigastric folds -Urinary bladder, -Seminal vesicle -ureters -rectum -Common iliac arteries and veins

What are the joints of the Pelvic girdle?

-Lumbosacral Joint -Sacraliliac Joint -Sacrococcygeal joint

What is the job of the puborectalis?

-Maintains fecal continence

What lies within the lateral ligament of the rectum? (3)

-Middle rectal artery and vein -Rectal nerve plexus

What goes thru the obturator canal?

-Obturator nerve (L2-L4), and artery pass thru

Peritoneal structures of the pelvic cavity in females? (9)

-Pararectal fossa -Paravesical fossa -Supravesical fossa -Uteric fold -Broad ligament* -Vesicouterine pouch/fossa* -Suspensory ligament of the ovary* -uterosacral fold* -Rectouterine pouch/fossa (of douglas)*

What are peritoneal structures of the pelvic cavity in males? (5)

-Pararectal fossa: Peritoneum over rectum and lateral to rectum -Paravesical fossa: lateral to bladder -Supravesical fossa -Uretic fold -Vesicosacral(sacrogenital) fold -Vesical=bladder

What structure supports the pelvic viscera?

-Pelvic diaphragm

Where are the pelvic fascias? What are the two distinct types?

-Pelvic fascias are inferior to the peritoneum but superior to the muscular pelvic diaphragm Two distinct types are: -Membranous fascia -Endopelvic fascia

What joints/articulations can be seen on the posterior view of the pelvic girdle?

-Posterior sacroiliac ligament -Sacrospinous ligament -Sacrotuberous liament

Why is the rectum at an 80 degree angle at the anorectal junction?

-Puborectalis m. forms the puborectal sling, which causes such an angle

Which space in males is the most inferior space to collect fluid from the peritoneal cavity?

-Rectovesical pouch/fossa

What is nutation and why does it happen? What ligament limits movement

-SI joint is synovial so allows around 4 degrees of movement -Nutation is movement of sacrum forward and distal tip of coccyx backward. Counternutation is the opposite -Limited by sacrospinous ligament

What boundaries make up the pelvic girdle/inlet? What does the inlet separate?

-Sacral promontory -Sacral alae -Linea terminalis -Superior pubic symphysis -Separates false and true pevlis

Is the greater sciatic foramen superior or inferior to the pelvic diaphragm? Is the lesser sciatic foramen superior or inferior to the pelvic diaphragm?

-Superior -Inferior

What structure are contained within the lateral ligament of the bladder? (2)

-Superior vesical artery and vein

What are the boundaries of the pelvic cavity?

-Superior:Pelvic Inlet & peritoneum -Inferior:Pelvic diaphragm; pelvic outlet -Lateral: Ischium, Obturator internus, Obturator fascia -Posterior:Sacrum & piriformis m. -Anterior:Pubic bones

What viscera can be found in the pelvic cavity of females? (6)

-Urinary bladder -Urethra -Uterus: Uterine tube, fundus, cervix -Rectum -Vagina -Ovaries

What are the viscera in the pelvic cavity of males (8)

-Urinary bladder: Apex, fundus, trigone, neck, ureteric orifice (where ureters empty) -Rectum -Seminal vesicles -Prostate -Ejaculatory duct -Ureter -Ductus deferens -Prostatic urethra: Where urethra goes thru prostate

What are the three parts of membranous fascia in females?

-Uterosacral ligament -Paracolpium -Pubovesical ligament

What can be seen looking inferiorly at the viscera in the pelvic cavity of females? (6)

-Uterus: Fundus, body, cervix -Rectum -Ovaries -Uterine tube -Round ligament passing through the deep inguinal ring -Bladder

The vesicouterine pouch and rectouterine pouch are in between what, respectively?

-Vesicouterine pouch: Between posterior bladder and anterior uterus -Rectouteterine pouch: Between posterior uterine and anterior rectum

What are the two layers of the membranous pelvic fasica?

-Visceral Layer: surrounds pelvic viscera -Parietal layer: surrounds pelvic floor

What percentage of pregnancies are at risk for dystocia/ fetopelvic diproportion?

1-3%

What are the risks of dystocia/ fetopelvic disproportion (difficult birth)?

1. Contracted pelvic diameters: -Obstetric conjugate -Transverse inlet -Interspinous -Transverse outlet 2. Excessive fetal size or malposition of fetus in birth canal 3. Gestational diabetes 4. Post-term pregnancy

What is the endopelvic fascia?

"Packing material" surrounding organs. Mostly made up of loose connective tissue and fat