Pelvis and Perineum Flashcards
What are the components of the pelvis? [6 things]
Ilium, ischium, pubis, sacrum, coccyx, pubic symphysis
What are the functions of the pelvic girdle?
Bear weight, transfer weight, and provide attachments for muscles
What is the superior border of the pelvis?
Pelvic inlet
What is the anterior border of the pelvis?
Pubic rami, pubic symphysis
What is the lateral border of the pelvis?
Hip bones and obturator internus
What is the posterior border of the pelvis?
Sacrum and coccyx, SI joint and ligaments
Between what two structures forms the greater (false) pelvis?
iliac crest and inlet
Between what two structures forms the lesser (true) pelvis?
Pelvic inlet to pelvic outlet
What does the greater pelvis contain?
abdominal viscera
What binds the greater pelvis?
iliac alae
What binds the lesser pelvis?
Pelvic surfaces of hip, sacrum, and coccyx
What structure covers the obturator foramen?
obturator membrane
What forms in the obturator foramen serving as the passage for the obturator nerve?
obturator canal
What structure forms from the anterior sacro-iliac ligament and sacrotuberus ligament?
Greater sciatic notch
What structure forms from the sacrotuberus ligament and sacrospinous ligament?
Lesser sciatic notch
Describe the male pelvis.
Thick and heavy, pelvic inlet is heart shaped and small, pubic arch is narrow, obturator foramen is round, acetabulum is large
Describe the female pelvis.
Thin and light, pelvic inlet is oval and rounded and large, pubic arch is wide, obturator foramen is oval, acetabulum is small
What is the subpubic angle of a male?
~<=70 degrees
What is the subpubic angle of a female?
~>=80 degrees
What are the muscles of the pelvic floor?
Levator ani: puborectalis, pubococcygeus, iliococcygeus and [ishio]coccygeus
Which levator ani forms the u-shaped puborectal sling?
Puborectalis
What is the function of the levator ani?
assist w/ abdominopelvic cavity compression (when coughing, sneezing, vomiting, etc)
What is the function of the coccygeus?
support pelvic viscera, form part of the diaphragm, flex the coccyx
What are the contents of the urogenital triangle?
Ischiocavernosus, bulbospongiosus, perineal membrane, superficial transverse perineal, perineal body, puborectalis
What urogenital muscle is along the line of the pubic bone?
Ischiocavernosus
What urogenital muscle surrounds the male penis/ female puborectalis?
Bulbospongiosus
What connects the ishiocavernosus and bulbospongiosus?
Perineal membrane
What does the perineal membrane cover?
pelvic diaphragm, iliococcygeus, and pubococcygeus
What goes straight from pubic bone to point where urogenital and anal triangles meet?
Superficial transverse perineal
What is the anterior boundary of the perineum?
pubic symphysis
What is the anteroleateral boundary of the perineum?
Ishiopubic ramus
What is the lateral boundary of the perineum?
Ischial tuberosities
What is the posterolateral boundary of the perineum?
sacrotuberous ligaments
What is the posterior boundary of the perineum?
inferiormost sacrum and coccyx
What type of pelvic fascia lines the inner aspects of the muscles, forming the walls and floor of the pelvis?
Parietal
Which pelvic fascia directly ensheathes the organs?
Visceral
Which pelvic fascia forms a connective tissue matrix for the viscera?
Endopelvic
What are the joints of the pelvic girdle?
Sacroiliac, pubic symphysis, lumbosacral, and sacrococcygeal
What is the name of the joint connecting the axial and appendicular skeletons?
sacroiliac
What joint joint the two hip bones?
Pubic symphysis
What does the lumbosacral joint consist of?
L5 and Si vertebrae and IV disc, 2 posterior facet joints
What type of joint is the sacrococcygeal?
Secondary cartilaginous
What ligament aids in the transfer of weight from axial to ilia to femur and ischial tuberosities?
Sacroiliac ligaments
What ligament attaches the sacrum to the iliac bones, aiding in weight transfer?
Interosseous ligament
What ligament creates the sciatic foramen by passing from the posterior ilium and lateral sacrum/coccyx to the ischial tuberosity?
Sacrotuberous
What ligament subdivides the greater and lesser sciatic foramen by passing from the lateral sacrum and coccyx to the ischial spine?
Sacrospinous
What ligaments connect the transverse processes of L5 to the ilia?
Iliolumbar
What ligament reinforces the joint of the sacrum apex to coccyx base?
Sacrococcygeal
What movement does the sacroiliac joint allo?
Slight gliding and rotation
What movement is prevented at the lumbosacral joints?
Sliding
What artery is the main supplier of the pelvis?
Internal iliac
What artery does the internal iliac begin as?
Common iliac
What arteries branch off the anterior branch of the internal iliac artery?
Obturator, pudendal, inferior gluteal
Which arteries branch off the posterior branch of the internal iliac artery?
Superior gluteal, iliolumbar, lateral sacral
What artery forms at the bifurcation of the R and L iliac arteries?
median sacral artery
What does the Median Sacral artery supply?
Anterior surface of sacrum with 2 IV foraminal branches at each pair
The R common iliac artery divides into what two branches?
External and internal iliac
What artery branches off the external artery?
Femoral
What other two arteries branch off the femoral artery?
Inferior epigastric and circumflex iliac
What artery supplies the anterior abdominal wall?
Inferior epigastric
What artery supplies the wall near the iliacus?
Circumflex iliac
What artery branches off the internal iliac and supplies the ilium and lumbar spine?
Iliolumbar artery
What does the internal iliac artery supply?
Pelvic organs, gluteal muscles, and perineum
What are the arteries that branch off the anterior division of the Internal iliac artery?
umbilical, Superior and inferior vesical, internal pudendal, middle rectal, inferior gluteal, obturator
What are the arteries that branch off the posterior division of the internal iliac artery?
Sacral arteries, superior gluteal, and iliolumbar
What two arteries supply the superior bladder and some males’ vas deferens?
Umbilical and superior vesical
What does the Obturator artery supply?
pelvic muscles, nutrient artery to ilium, head of femur, and muscles of the medial thigh
What artery supplies the inferior male bladder, pelvic part of ureter, and the prostate and seminal glands?
Inferior vesical
What does the internal pudendal artery supply?
main artery of the perineum (incl. skin and muscles of anal and urogenital triangles and erectile bodies)
What artery supplies the inferior rectum, seminal glands, and prostate/vagina?
middle rectal
What does the inferior gluteal artery supply?
Pelvic diaphragm (main supplier of), piriformis, quad fem, hamstrings, glut max, and sciatic nerve
what artery supplies the psoas major, iliacus, and quad lumb as well as the cauda equina?
Iliolumbar
What do the sacral arteries supply?
piriformis, sacral canal, erector spinae, and overlying skin
What artery supplies the piriformis, all three glutes, and the tensor fasciae latae?
Superior gluteal
What is a herniation of the urethra/vagina wall?
Cystocele
What is a herniation of the rectum?
Rectocele
What is the name given to a normal female pelvis? (Rounded inlet, wide transverse diameter)
Gynecoid
What is the name given to the normal heart shaped male pelvis?
Platypelloid/android
What is fractured when the acetabulua and ilia are squeezed together?
pubic rami
What is fractured by a fall from above?
Acetabulum
What is the defect that allows part of the vertebral arch to separate from the body?
Spondylolysis
What is the name given to a bilateral L5 spondylolysis that slides anteriorly so that it overlaps the sacral promontory?
Spondylolisthesis
What are the most common muscles torn during childbirth?
Puborectalis and pubococcygeus
What can stretching or tearing of the muscles supporting the urogenital organs cause?
Urinary stress incontinence
What tearing of the puborectalis (during childbirth usually) cause?
Fecal incontinence
What is the name given to a prolapsed urethra?
Urethrocele
What is the name given to a prolapsed bladder?
Cystocele
What is the name given to a prolapsed uterus, cervix, and/or upper vagina?
Uterovaginal prolapse
What is the name given to a prolapses rectovaginal pouch?
Enterocele
What are the four degrees of a prolapse?
- halfway to hymen 2. to hymen 3. past hymen 4. maximum descent
What are the possible treatments for prolapses?
Kegels, surgery, pessaries (devices inserted into vagina for support)
What is a surgical incision of the perineum and vaginal wall to enlarge the orifice to attempt t decreases jagged tearing during childbirth?
Episiotomy
What can a fracture of the pelvic girdle cause?
rupture of urethra
What can occur due to a disappeared pelvic fat pad by starvation?
rectal prolapse
What is the landmark that provides the approximated level of important anatomical changes as the visceral and parietal layers transition?
Pectinate line
What is a slit-like lesion near the anal valve?
Anal fissure
What can occur due to the spread of infection and cyryptitis (inflam. of anal sinus)?
Anal fistula
What is a prolapse of the rectal mucosa?
Internal hemorrhoid
What is a thrombus in the veins of rectal venous plexus and covered by skin?
External hemorrhoid
What are the predisposing factors for hemorrhoids?
Pregnancy, chronic constipation, prolonged toilet sitting and straining, and any disorder that impedes venous return
What vein mainly drains the pelvic venous plexuses by interjoining veins?
Internal iliac veins
What do the internal iliac veins merge with to unite at L4/5 to form into the IVC?
common iliac veins
What are the tributaries of internal iliac veins into the gluteal region?
Superior gluteal veins
What veins provide collateral pathways to reach IVC or SVC, that anatomose with internal vertebral venous plexus?
Lateral Sacral veins
What is the nerve that supplies the mid thigh?
Obturator nerve
What is the origin of the obturator nerve?
ant rami of L2-4
What nerve supplies the hip joint and muscular branches of the knee flexors and all leg and foot muscles? Where does it originate?
Sciatic nerve, L4-S3
What nerve is the main supplier of the perineum and external ganglia, and the muscles and sphincters that go to them? And where does it originate?
Pudendal nerve, S2-4
What does the superior gluteal nerve supple and where does it originate?
L4-S1, Gluteus medius and minimus, and the tensor fasciae latae
What muscle does the inferior gluteal nerve supply and where does it originate?
Gluteus maximus, L5-S2
Where does the nerve to the quad fem originate and what other muscle does it supply?
L4-S1, inferior Gemellus
Where does the nerve to obturator internus originate and what other muscle does it supply?
L5-s2, superior Gemellus
Where does the nerve to piriformis origintate?
S1, S2
What does the posterior cutaneous nerve of thigh supply and where does it originate?
S2, S3, buttocks and uppermost medial and posterior thigh
What branches come off the posterior cutaneous that supply the medial buttocks?
Perforating cutaneous
What nerve supplies the pelvic viscera via inferior hypogastric and pelvic plexuses? Where is the origin?
Pelvic sphincter nerve, S2-S4
Where does the nerve to levator ani and coccygeus originate?
S3, S4
What is the excision of an ovary?
oophrectomy
What structures are in danger during an oophrectomy?
Ureters
