Pelvic Viscera Flashcards
Pelvic Girdle Components (3)
-Sacrum
-Innominate bones
-Coccyx
Innominate Bones Main Features (3)
-Ilium
-Ischium
-Pubis
Joints of Pelvis
- Sacroiliac joints
-Auricular surfaces of sacrum and ilium - Symphysis pubis
-Fibrocartilaginous disc b/t left and right pubis (symphyseal surfaces)
Pelvic Inlet vs. Outlet (4 and 3 Borders)
Inlet borders:
-Sacral promontory
-Sacral ala
-Iliopectineal line
-Symphysis pubis
Outlet borders:
-Coccyx
-Ischial tuberosities
-Symphysis pubis
True vs. False Pelvis
True pelvis= more inferior, supports inferior viscera
False pelvis= more superior (larger bony parts), support more superior pelvic viscera
Male vs. Female Pelvis (2 Differences)
Subpubic angle and interspinous distance= both larger for females for child-bearing
Pelvic Diaphragm- Function, Features and Muscles
Function: support pelvic viscera
Features: urogenital hiatus and anal aperture
Muscles: levator ani group (puborectalis, pubococcygeus, iliococcygeus) and coccygeus
*puborectalis forms urogenital hiatus and keeps rectum in position (‘anal sling’)
Pelvic Viscera- Male (4) vs. Female (4) + Both (4)
Male:
-Vas deferens
-Seminal vesicles
-Ejaculatory ducts
-Prostate gland
Female:
-Uterus
-Uterine tubes
-Ovaries
-Vagina
Both:
-Bladder
-Ureters
-Sigmoid colon
-Rectum
Broad Ligament
-Covers female pelvic viscera (entire cavity)
-Double fold of peritoneum
-3 divisions: mesometrium, mesovarium and mesosalpinx
Mesometrium
-Largest division of the broad ligament
-Covers the uterus and bladder
Mesovarium
-Suspends ovaries from uterine tubes
Mesosalpinx
-Surrounds uterine tubes
Uterus Components (5)
-Fundus (top dome shape)
-Uterine cavity
-Cervix
-Internal and external O’s
-Cervical canal
Uterus Ligaments (3)
- Uterosacral ligament
- Cardinal ligament
- Round ligament
Uterine Tubes Components
-Isthmus
-Ampulla
-Infundibulum
-Fimbriae
Ovaries
-Paired almond shaped organs
-Produce ova (eggs)
-Secrete estrogen and progesterone
-Suspensory ligament anchors ovaries to pelvic side wall
-Located superior to uterus
Vagina
-Open to external environment
-Begins at external O’s of the cervix
-Posterior to bladder
-Protrusion of cervix creates fornixes (medial and lateral)
Seminal Vesicles
-Posterior surface of bladder
-Lateral to ductus deferens tubes
-Glandular structures
-Store and produce fluid that makes up majority of semen
Ejaculatory Ducts
-Formed by union of seminal vesicles and ductus deferens
Prostate Gland
-Inferior to bladder
-Walnut shaped
-Traversed by prostatic urethra
-Prostate utricle contracts to widen the openings of the ejaculatory ducts
-Produce seminal fluid that nourishes and transports sperm
-Semen enters urethra through prostate
-Plays a role in hormone production and helps regulate urine flow
Rectum
-Continuous with anal canal distally
-2 flexures: sacral flexure and anorectal flexure
-3 transverse folds (superior, inferior and middle) and 3 lateral flexures
Ureters
-Exit renal pelvis
-Pass posterior to gonadal vessels and anterior to psoas major
-Pass anterior to iliac vessels
-Enter posterior aspect of bladder
Bladder Components (6)
-Apex
-Body
-Ureters (dump into bladder)
-Internal urethral orifices
-Trigone (b/t 3 orifices)
-Urethra
Relational Anatomy: Males
Central organ: prostate gland
Anterior: symphysis pubis
Posterior: seminal vesicles
Superior: bladder
Inferior: pelvic diaphragm
Relational Anatomy: Females
Central organ: bladder
Anterior: symphysis pubis
Posterior: vagina
Superior: uterus
Inferior: pelvic diaphragm
Blood Supply Overview
-Common iliac artery -> internal iliac artery and external iliac artery
-Gonadal arteries
-Inferior mesenteric artery
Uterus Blood Supply
Internal iliac artery -> uterine artery
Ovaries Blood Supply
Abdominal aorta -> left and right ovarian arteries
Rectum Blood Supply
Inferior mesenteric artery -> superior rectal artery
Internal iliac artery -> middle and inferior rectal artery
Innervation of Pelvic Viscera
-Innervated by the autonomic nervous system
-Parasympathetic and sympathetic
Sympathetic Innervation
- Preganglionic neurons in L1 and L2
- Inferior mesenteric ganglion or inferior hypogastric plexus
- Pelvic viscera
*Inhibits bladder, excited internal urethral sphincter (prevents urination)
*Inhibits peristaltic contraction, excites internal anal sphincter (prevents defecation)
*Excites uterine contraction
Parasympathetic Innervation
- Preganglionic neurons: S2, S3, S4
- Pelvic splanchnic nerves
- Pelvic viscera
*Excites bladder, inhibits internal urethral sphincter (allows urination)
*Excites peristaltic contraction, inhibits internal anal sphincter (allows defecation)
*Inhibits uterine contraction
