Urinary Bladder - Anatomy & Physiology

BACK TO URINARY - ANATOMY & PHYSIOLOGY

• The bladder is where urine is stored before being expelled by the body through the micturition reflex.
• Without a bladder urinary continence would be impossible.

Anatomy

• It is a hollow, muscular organ
• It is divided for descriptive purposes into three parts
  • Cranial Pole
  • Intermediate body
  • Caudal neck
• Its size and posistion are determined by how full it is.
  • When empty the bladder wall is wrinkled and thicker
  • When full and distended the folds dissapear and the wall appears thinner
• The paired uteric folds are visible even when the bladder is full.
  • They extend from the ureteral opening to the neck of the bladder
  • Here they merge
  • Forms the urethral crest - continues into the urethra

The Ligaments of the Bladder

• Two lateral ligaments
  • Insert in the dorsal abdominal wall
  • Within them are the residual umbilical vessels

• Median ligament
  • Connects the bladder to pelvic floor and linea alba

Blood Supply, Innervation and Lymphatic Drainage

Blood Supply - Caudal vesicular artery

Sympathetic Innervation - Via hypogastric nerve from the caudal mesenteric ganglion

Parasympathetic Innervation - Pudendal nerve

Lymphatic Drainage - Iliosacral lymph nodes