Pelvis & Pelvic Viscera Learning Objectives Flashcards
Name the bony elements of the pelvic girdle
L., basin
Innominate x 2
Sacrum
Coccyx
Name the structures that form the boundaries of the pelvic inlet (brim)
divides pelvis into greater (false) and lesser (true)
- Sacral promontory
- Arcuate line
- Pectineal line
- Pubic symphysis
Name the structures that form the boundaries of the pelvic outlet
- Coccyx
- Sacrotuberous ligament
- Sacrospinous ligament
- Ischial tuberosities
- Pubic arch
Describe the divisions of the pelvis
Abdominal cavity
Greater pelvis (false): superior to pelvic brim
Lesser pelvis (true): inferior to pelvic brim, superior to pelvic outlet
Name the pelvic joints and ligaments that cross them
Anterior/posterior sacroiliac ligaments
- Sacrum to innominate; stabilizer
Sacrospinous ligament
- Sacrum to ischial spine
Sacrotuberous ligament
- Sacrum to ischial tuberosity
Anterior longitudinal ligament
- Spans the anterior aspect of lumbar spine/sacrum
Iliolumbar ligament
- Ilium to TP of 5th lumbar vertebrae
List the ways the male and female pelvis differ from one another
Subpubic angle is primary identifier
- Male
o subpubic angle: 70 deg
o Heart-shaped inlet
o Narrow outlet
o Narrow cavity
o Narrow, convex sacrum - Female
o subpubic angle: 90-100 deg
o Oval-shaped inlet
o Roomy outlet
o Roomy cavity
o Wide, flat sacrum
Describe the basic structure of the pelvic viscera
???
Terminal parts of digestive and urinary systems
Describe the structure and course of the ductus (vas) deferens
Conveys sperm to ejaculatory duct
- Travels through inguinal canal
- Superior to ureter
- Posterior to urinary bladder
- Merges with seminal glands to form ejaculatory ducts within prostate
Describe the location of the prostate
Inferior to urinary bladder
Surrounds prostatic urethra
Contributes alkaline fluid
Describe the location of the bulbourethral glands
Inferior to prostate
Within perineal membrane
Contributes lubricating secretions into spongy urethra
Name the four parts of the male urethra
*Preprostatic
Prostatic part
Membranous part
Spongy part
Describe the basic structure of the female internal reproductive organs: OVARIES
Ligaments:
- ovarian
- suspensory
Peritoneal folds:
- mesovarium
- mesosalpinx
- mesometrium
composed of dense fibrous tissue in which ova are produced and discharged from follicles (ovulation)
Ovarian vessels (in ovarian suspensory ligament)
Mesovarium
Surrounds ovarian and suspensory ligaments, ovarian vessels
Mesosalpinx
Surrounds uterine tubes
Mesometrium
surrounds uterine vessels
Describe the basic structure of the female internal reproductive organs: UTERINE TUBES
Fimbria
Ampulla
Infundibulum
Isthmus
Direct the oocyte from peritoneal cavity to the uterine cavity
Describe the basic structure of the female internal reproductive organs: UTERUS
Fundus
Corpus
Cervix (neck)
Internal and external os
Thick-walled muscular organ; fetal development and delivery
Describe the basic structure of the female internal reproductive organs: VAGINA
Cervical canal –> vaginal vestibule
Vaginal fornix
Anterior/posterior walls
Vaginal orifice
Vaginal vestibule with labium minora
Uterine, vaginal, internal pudendal vessels
Canal for menstrual fluid; inferior part of birth canal; sexual intercourse
Describe the location and general function of the perineum
Shallow, narrow compartment
Inferior to pelvic floor muscles/fascia
Supports openings from the pelvic floor
Name the boundaries and contents of the male and female perineum
Boundaries:
- Pubic symphysis
- Ischiopubis rami
- Ischial tuberosities
- Sacrotuberous ligaments
- Sacrum/coccyx
Anterior division: urogenital triangle
Posterior division: anal triangle
Includes genitals and anus
Describe the location of the erectile tissues of the female
Glans of clitoris
Vestibular bulb (bulbospongiosus m.)
Crus of clitoris (ischiocavernosus m.)
Describe the location of the erectile tissues of the male
Corpus cavernosum (enlargement: glans of penis; covered by ischiocavernosus m.)
Corpus spongiosum (bulb of penis; covered by bulbospongiosum)
Describe the ischioanal fossa including contents
- Fats pads and loose connective tissue
- Found in anal triangle
- Bordered by levator ani and obturator internus mm.
- Provides support to rectum (prevent prolapse)
- Contains pudendal canal (pudendal n., internal pudendal a/v)
List the structures comprising the male external genitalia
Distal urethra
Penis
Scrotum
Anus
List the structures comprising the female external genitalia
Vulva
- mons pubis
- labia majora
- labia minora
- clitoris
- vaginal opening
- urethral opening
Anus
Describe the internal features of the scrotum
Scrotum
Tunica dartos
External spermatic fascia
Cremasteric fascia and cremaster muscle
Internal spermatic fascia
Tunica vaginalis, parietal layer
Testis with tunica vaginalis, visceral layer
Describe the course and branches of the pudendal nerve
Descends vertically through sciatic foramina (around pelvic floor)
- Leaves pelvis via greater sciatic foramen
- Re-enters pelvis via lesser sciatic foramen
Branches
- inferior rectal n.
- perineal n.
– deep
– superficial
– posterior labial/scrotal
- dorsal nerve of penis/clitoris
Components of pudendal n. responsible for male erection
Smooth mm. of corpora cavernosa relax
Parasympathetic s2-4; cavernous nn. extensions of prostatic plexus
Components of pudendal n. responsible for male ejaculation
Contraction of internal genital organs
Sympathetic L1-2; lumbar splanchnics to hypogastric plexus
Explain the characteristics of the anal canal
Pelvic diaphragm –> anus
External/internal anal sphincters
