What muscles make up the lateral pelvic sidewall above the arcus tendineus?
piriformis, obtuator internus, iliopsoas
What is the orgin of the piriformis?
sacrum, (overlain by the sacral plexus coccygeus associate with the coccyx)
What is the insertion of the piriformis?
What does the piriformis do?
lateral rotation, abduction of thigh, bed for sacral plexus
What is the innervation of the piriformis?
innervation S1 to S2
What is the origin of the obturator internus?
superior and inferior pubic rami exits lesser foramena
What is the insertion of the obturator internus?
inserts on greater trochanter
What does the obturator internus do?
lateral rotation of thigh
What is the innervation of the obturator internus muscle?
L4 to S1 obturator internus n.
What is the origin of the iliopsoas?
psoas lateral margin of lumbar vertebrae, iliacus iliac fossa
What is the insertion of the iliopsoas?
lesser trochanter of femur
What is the function of the iliopsoas muscle?
action flexes thigh, stab. spine
What is the innervation of the iliopsoas muscle?
psoas L1 to 3 iliacus L2 to 3
What structures rest on the psoas muscle?
overlain by tendon of psoas minor and genitofemoral nerve
What is the origin of the levator ani?
tendinous arch from pubis to ischial spine
What is the insertion of the levator ani?
insertion central tendon, wall of anal canal (puborectalis), wall of vagina (pubovaginalis), anococcygeal lig, coccyx (pubococcygeus)
What is the function of the levator ani?
support, bm mechanism, supports fetal head
What is the innervation of the levator ani?
S3 to S4 via inferior rectal n
What is the origin of the coccygeus
ischial spine & sacrospinus ligament
What is the insertion of the coccygeus?
lateral margin of 5th sacral vertebra and coccyx
What is the function of the coccygeus?
supports coccyx and pulls it ant.
What is the innervation of the coccygeus?
S4 to S5
What are 2 muscles of the urogenital diaphragm?
deep transverse perineal and sphincter urethrae complex
What is the origin insertion, action and innervation of the deep transverse perineal muscle?
origin: med. aspect of ischiopubic rami insertion: lower vaginal wall action: steadies central tendon innervation S2 to S4 perineal n
What is the origin insertion, action, and innervation of the sphincter urethrae?
origin: medial aspect of ischiopubic rami insertion: urethra and vagina action: compresses urethra innervation S2 to S4
What makes up the lateral walls of pelvis below the arcus tendineus?
Name the 3 types of peritoneal fascia.
1. parietal covers muscles continuation of transversalis fascia includes arcus tendineus. 2. diaphragmatic : covers urogenital diaphragm Has two layers (internal and external) Internal or superior layer is strongest. 3.endopelvic fascia covers the three tubular structures
What is the hiatus of Schwalbe?
space between the levators and obturator fascia that may herniate to ischiorectal fossae/suprategmental space.
What is the boundary of the perineum?
symphysis, coccyx, inferior pubic ramus, ischial rami, ischial tuberosities, sacrotuberous ligaments. (External to the levators)
What is the line of Hart?
mucocutaneous junction found in the vagina
Name the 5 muscles that insert on the perineal body.
bulbocavernosus x2, superficial transverse perineal x 2 deep transverse perineal x2, levator ani, external sphincter
Describe the path of the pudendal(Alcock's) canal.
runs from post ischirectal fossa at lesser sciatic foramen at edge of urogential diaphragm
What supports the lower 1/3 of the vagina?
arcus tendineus, UGD, perineal body
What supports the middle 1/3 of the vagina?
What supports the upper 1/3 of the vagina?
cardinal and uterosacral ligaments
Name the four arteries that supply the vagina.
Vaginal artery, vaginal branch from uterine a, middle rectal, internal pudendal
What are the azygos arteries of the vagina?
midline fusion of vaginal arteries, analogous to inferior ves aa in the male
What nodes would be positive soonest in a patient with vaginal cancer involving the upper 1/3 of the vagina?
What is usually the first artery divided during abdominal hysterectomy?
Artery of Sampson (contained within the round ligament)
Describe the path of the round ligament.
Inserts in canal of Nuck deep inguinal ring, runs around inf epigastric vessels becomes extraperitoneal and crosses the obliterated hypogastric a. to insert in labia majora
What ligament primarily holds the cervix and vagina over the levator plate?
What is the superior boundary of pouch of Douglas?
Insertion of the uterosacral ligaments
What nerves travel in the uterosacral ligaments?
parasympathetic and sympathetic fibers from the hypogastric plexus
What structure suspends the urethra from the pubic bone?
You are doing a C section. You have divided the rectus muscles and entered the peritoneum. As you extend your incision toward the bladder, you divide thick connective tissue bands overlaying the peritoneum. What are they?
What is the difference between a pertoneal fold and a peritoneal ligament?
A ligament is a double layer of peritoneum covering a neurovascular structure. A fold appears over a single tubular structure (obliterated?) blood vessel or ureter
Name the major branches of the inferior mesenteric artery.
left colic (transv. to descending colon) sigmoid, superior rectal.
What are the 5 branches of the external iliac artery?
superficial epigastric, external pudendal, superficial circumflex iliac, inferior epigastric, deep circumflex iliac of sciatic foramen.
You are doing a Burch procedure and dissect out just a little to far. Your field fills with venous blood. What vessel was injured?
Plexus of Santorini
You are doing a Burch procedure and dissect just a little to far laterally. You encounter a brisk arterial bleeder. What vessel have you injured?
Aberrant obturator (in 35% the pubic branch of inferior epigastric is large and replaces obturator)
What are the branches of the internal pudendal artery?
inferior hemorrhoidoal, perineal, clitoral.
Is the pudendal artery medial or lateral to the nerve?
In what structure does the middle hemorrhoidal artery appear?
What nerve innervates the skin of iliac crest and pubis?
What nerve penetrates external oblique 1 to 2 cm superomedial to superficial ring?
Iliohypogastric L1 sensory
What nerve innervates the upper medial thigh and mons labia majora and pubis?
Ilioinguinal L1 (anterior labial nerve)
What nerve passes through the inguinal canal?
What nerve overlays the psoas muscle?
Genitofemoral L1 to L2
What nerve provides sensation to the anterior vulva and middle/upper anterior thigh?
Genitofemoral L1 to L2
How does the genitofemoral nerve exit the pelvis?
genital branch via inguinal ring femoral branch below ing lig.
What nerve provides sensation to the lateral thigh?
Lateral Femoral Cutaneous L2 to L3
What nerve supplies sensory to anterior medial leg and motor to the iliacus quads?
Femoral L2 to L4
What nerve provides sensory innervation to medial thigh
leg, hip, and knee? It also provides motor branches to the adductors of thigh.,Obturator L2 to L4
You are doing a lymph node dissection. You have moved the iliac vessels medially with a vein retractor and are dissecting with the Bovie. A nerve is triggered and the pts leg moves. What is the nerve?
Obturator L2 to L4
What 2 nerves supply only motor fibers to gluteal mmuscles?
superior gluteal n. (L4, L5, S1) and inferior gluteal n (L4, L5,S1,S2)
What nerve provides sensation to the vulva and perineum?
posterior femoral cutaneous S2,S3
What nerve provides sensory innervation to leg and motor fibers to the posterior thigh leg and foot?
What nerve provides sensory innervation to the perianal skin vulva perineum, clitoris, urethra, and vestibule?
What nerve provides motor innervation to the external sphincter perineal mm and urogential diaphragm?
What muscle does the pudendal nerve cross?
What nerve emerges within the inguinal canal and through the superficial inguinal ring to supply the mons & upper labia major?
anterior labial n. : branch of ilioinguinal
What is the path of the genital branch of the genitofemoral nerve?
enters the inguinal canal with the round ligament exits the superficial inguinal ring to anterior vulva.
What is the path of the perineal branches of the posterior femoral cutaneous nerve?
exit via GSF run anterior to ischial tuberosity to lateral perineum and labia majora
What nerves innervate the skin over the coccyx and sacrum?
Perforating cutaneous branches of the second and third sacral nn ; perforate the sacrotuberous ligament to supply the buttocks and perineum anococcygeal nn S4 to 5 perf. sacrotuberous lig. to supply skin of coccyx
Where is pain from uterine contractions carried?
T10,11,12th nerve roots
What is Frankenhauser nerve plexus?
a condensation of uterovaginal nn on either side of cx that contains sympathetic (contraction) and parasympathetic (relaxation)nn to uterus, bladder, vagina. ympathetic nerves also reach the uterus in association with uterine arteries.
Where are the parasympathetic fibers (S1 to 4 via nervi eregentes) found?
Fibers run in anterior two thirds of u/s ligaments.
Where do sympathetic nerves synapse?
synapse is remote from organ ie lumbar sympathetic chain
Where do parasympathetic nerves synapse?
on target organ ; sacral
Where are the sympathetic trunks located?
lie on medial border of psoas muscle, pass behind common iliac v. on anterior sacrum.
Where is the aortic plexus?
anteriolateral surface of aorta, gets rami from sympathetic trunks.
What structures are innervated by the ovarian plexus?
ovaries, tube, broad ligament, this plexus is derived from aortic/renal plexus
What is the name for the continuation of the aortic plexus in the pelvis?
superior hypogastric plexus a.k.a. presacral nerves (a continuation of aortic plexus) retroperitoneal, in front of terminal aorta, L5, sacral promontory, medial to ureters, over middle sacral v.,
What types of nerves are found in the superior hypogastric nerves?
preganglionic fibers from lumbar n., postganglionic fibers from sympathetic nn., postganglionic fibers from sacral sympathetic trunks, viceral afferent fibers.
After passing the sarcal promonotory what is the fate of the superior hypogastric plexus?
Below the sacral promontory, the superior hypogastric plexus divides into hypogastric nn.. These move inferiorly and laterally to connect to inferior hypogastric plexus which overlie the internal iliac vessels.
What fibers are found in the inferior hypogastric plexus?
efferent sympathetic fibers, sensory fibers, parasymp. from S2 to S4
What structures does the inferior hypogastric plexus innervate?
This paired plexus divides into three portions to innervate the pelvic viscera as the Vesical plexus, Middle rectal plexus, and the Uterovaginal plexus.
What structures does the vesical plexus innervate?
Vesical plexus (branch of the hypogastric plexus) innervates the bladder and urethra which courses along vesical vessels.
What structures does the middle rectal plexus innervate?
Middle rectal plexus (branch of the inferior hypogastric plexus)innervates rectum and follows the middle rectal vessels.
What structres does the uterovaginal plexus innervate?
Uterovaginal plexus (Frankenhauser) innervates the uterus, vagina, clitoris, vestibular bulbs runs along uterine vessels (through the cardinal) and uterosacral ligaments, carries sympathetic and sensory fibers from T10 to L1, parasympathetic fibers from S2 to S4
What is the path of afferent innervation of the pelvis?
Follows blood vessels, first synapse in posterior spinal nerve gangila
The ventral mesentery of the primitive forgut persists as what structures?
The liver arises dividing mesentery into lesser omentum and falciform ligament.
The ventral mesentery of the primitive hindfut remains as what structure?
The dorsal mesentery of the secondarily retoperitoneal bowel froms what structure?
line of Toldt
Describe the development of the urinary system.
Begins with nephrogenic cord, then pronephros forms & fades. Then the mesonephros forms. The mesonephric duct lays groundwork of kidney and becomes the male duct .Uteric buds arise from mesonephric duct to form connection to metanephric blastema which induces formation of the kidney. Originally get blood from middle sacral artery. Inferiorly, the mesonephric duct connetion to outside dilates to form cloaca.
When does the genital system differentiate?
Describe the migration of the germ cells in early development.
Germ cells migrate from yolk sac via the mesentery of hindgut to T10
Describe the fusion of the Mullerian ducts.
Mullerian (paramesonephric) ducts form lateral to mesonephric ducts and grow caudally and fuse in the midline unless TDY and AMH are present.
What stage of the cell cycle are the germ cells in the pre pubescent female?
Germ cells enter 1st meiotic division & arrest until puberty.
Describe the fusion of the paramesonephric ducts.
Paramesonephric duct grows. Inferior fused portion recanalizes and becomes uterovaginal canal (epithelium/glands of uterus/vagina) surrounding mesenchyme forms endometrial stroma and myometrium.
What embryonic structure froms the vagina?
Vagina forms in third month from sinovaginal bulbs.
What two structures does the gubernaculum become?
ovarian ligament & round ligament
What embryonic structure form the external genitalia?
What happens embryonically when renal agenisis occurs?
ureteric buds fail to induce metanephric blastema, associated with ipsilat. absence of Muellerian str.
*Name 3 mesonephric remants that form cysts?
paroophoron epoophoron Gartner's duct
How many layers in the detrusor muscle?
3 Layers are not distinct at the dome. At the base, they are outer longitudinal, intermediate oblique layer, inner plexiform ( trabecullations on cysto)
What is Heiss's loop?
A U shaped band of tissue in the vesical neck that may add sphinceteric function as it is paired with a second unnamed U shaped band, each straddles the urethra, but from opposite directions.
What type of muscle fibers are present in the sphincter?
What are the three parts of the trigonal muscle?
Urinary trigone : anatomic landmark for finding the ureteral orifices, trigonal ring ( :adrenergic ring of tissue that is the most proximal cont. mechanism. Trigonal plate : a long fiber parallel to and on the vaginal side of the urethra that completes the circle of the U shaped striated sphincter
Describe the two portions of the urogenital sphincter?