Pelvis Viscera

Viscera of the Pelvis

• Organs located within the pelvis:
  • Gastrointestinal organs
  • Urinary organs
  • Reproductive organs and accessory structures (sex-dependent)

Gastrointestinal Viscera in the Pelvis

• Cecum and ascending colon: located in the greater pelvis on the right side
• Descending colon: becomes continuous with the sigmoid colon at the pelvic brim
• Sigmoid colon: joins with the rectum at the level of the mid-sacrum and becomes fixed to the posterior pelvic wall
• Rectum: follows the curvature of the sacrum and coccyx onto the pelvic floor, where it penetrates the levator ani muscle and becomes the anal canal

Female Reproductive Organs

• Organs and structures:
  • Ovaries
  • Ovarian tubes (also known as Fallopian tubes or uterine tubes)
  • Uterus
  • Vagina
• Ligaments:
  • Broad ligament (x2): holds the uterus and ovaries
  • Round ligament (x2): extends from the uterine horns to the anterior pelvic wall
  • Uterosacral ligament (x2): connects the uterus to the sacrum
  • Lateral cervical (cardinal) ligaments (x2): extend from the lateral walls of the cervix to the pelvic floor
  • Anterior ligament (x1): anterior cul-de-sac (ACDS) / vesicouterine pouch
  • Posterior ligament (x1): posterior cul-de-sac (PCDS) / pouch of Douglas / rectouterine pouch

Ligaments Associated with the Ovaries

• Mesovarium: attaches the ovary to the posterior layer of the broad ligament
• Ovarian ligament: a cord-like thickening within the broad ligament, attaches the ovary to the lateral wall of the uterus
• Suspensory ligament: an extension of the broad ligament, carries ovarian vessels and attaches the ovary to the pelvic wall

Ovaries and Uterine Tubes

• Ovary: a small, solid, oval structure, 3 cm long, containing 250,000 primary oocytes at birth
• Uterine tubes: slender tubes, about 10 cm long, located in the upper border of the broad ligament
• Infundibulum: the funnel-shaped distal portion of the uterine tube, edged with fingers-like extensions called fimbriae

Basic Physiology Review

• Uterine lining thickens in preparation for an embryo
• Ovary releases a mature oocyte into the peritoneal cavity
• The oocyte is swept into the uterine tube by fimbriae and propelled into the uterus by cilia in the uterine tubes
• Fertilization usually occurs in the uterine tube, and the zygote will implant in the uterine wall for subsequent development

External Female Genitalia

• Vulva (also known as pudendum): the collective term referring to all portions of the external female genitalia
• Mons pubis: a subcutaneous fat pad anterior to the symphysis pubis
• Labia majora: two large folds of skin filled with subcutaneous fat, located at the lateral margins of the vulva
• Labia minora: two thin, delicate folds of skin located medial to the labia majora but lateral to the urethral and vaginal openings
• Clitoris: located inferior to the mons pubis and between the anterior ends of the labia minora
• Vestibule: a narrow cleft between the two labia minora, bordered by the clitoris at the anterior end
• Urethral orifice: opens into the anterior portion of the vestibule
• Vaginal orifice: opens within the vestibule, posterior to the urethra
• Paraurethral and greater vestibular glands: secrete mucous for lubrication, located on either side of the urethral and vaginal orifices