Rigi10™ Malleable Penile Prosthesis
Also Known As
Urinary system, renal system, excretory system, genitourinary tract, urogenital system, renal tract
Definition
The urinary tract is the body’s drainage system for removing urine, which is composed of waste products and excess fluid filtered from the blood. The urinary system includes four main components: the kidneys, ureters, bladder, and urethra, all of which must work together in the correct order for normal urination to occur.1
The kidneys are two bean-shaped organs, each about the size of a fist, located just below the rib cage on either side of the spine.2 They filter approximately 120-150 quarts of blood daily to remove wastes and balance fluids, producing about 1-2 quarts of urine per day.3 Within each kidney are millions of nephrons, the functional units responsible for filtration, containing glomeruli that filter blood and tubules that return needed substances to the blood and remove wastes.4
The ureters are two thin tubes of muscle, approximately 9 inches long, that carry urine from the kidneys to the bladder.5 Muscles in the ureter walls continually tighten and relax, forcing urine downward and away from the kidneys, preventing backflow that could lead to kidney infection.6
The bladder is a hollow, muscular, triangle-shaped organ located in the lower abdomen that serves as a reservoir for urine.7 It can expand to store up to 1.5-2 cups of urine for 2-5 hours, with walls that relax and expand during filling and contract and flatten during emptying.8 The bladder contains two types of sphincter muscles that help prevent leakage by closing tightly around the opening of the bladder.9
The urethra is a tube that connects the bladder to the outside of the body, allowing urine to exit during urination.10 In females, the urethra is about 1.5 inches long, while in males it is approximately 8 inches long and also serves as a pathway for semen during ejaculation.11 The brain signals the bladder muscles to tighten and the sphincter muscles to relax when urination occurs.12
Clinical Context
Understanding urinary tract anatomy is essential for diagnosing, treating, and preventing various urological conditions. Clinically, knowledge of this anatomy is applied in the evaluation of patients with urinary tract infections (UTIs), kidney stones, urinary incontinence, and obstructive disorders.1
Urinary tract infections, which affect more than 60% of females at least once in their lifetime, occur when bacteria enter the urinary tract through the urethra and begin to multiply.2 These infections can affect any part of the urinary system but most commonly involve the lower urinary tract (bladder and urethra).3
Kidney stones (nephrolithiasis) form when waste products in the urine crystallize and build up on the inner surfaces of the kidney.4 Understanding the anatomy of the urinary tract is crucial for tracking the passage of stones and determining appropriate interventions, which may include medical expulsive therapy, extracorporeal shock wave lithotripsy, or surgical removal.5
Urinary incontinence, affecting more than half of individuals who have given birth, results from weakened pelvic floor muscles or dysfunction of the sphincter mechanisms.6 Treatment approaches, including behavioral techniques, pelvic floor exercises, medications, and surgical interventions, are based on a thorough understanding of urinary tract anatomy and function.7
Obstructive disorders, such as benign prostatic hyperplasia in males or pelvic organ prolapse in females, can impede the normal flow of urine through the urinary tract.8 Diagnostic imaging techniques, including ultrasound, CT scans, and MRIs, rely on knowledge of normal urinary tract anatomy to identify structural abnormalities and guide treatment decisions.9
Chronic kidney disease, affecting approximately 37 million people in the United States, progressively impairs the kidneys’ ability to filter blood and maintain fluid and electrolyte balance.10 Regular assessment of kidney function through blood tests, urinalysis, and imaging studies is essential for early detection and management of this condition.11