Introduction The urinary organs consist of ureters (pelvic portion) carries urine from the kidney into the bladder urinary bladder the site of temporary urine storage urethra the conduction site of urine from the urinary bladder to the external world Ureters Muscular tubes that carries urine from the kidney into the bladder they are retroperitoneal structures that pass beneath the uterine artery (in females) clinical correlate uterine or ovarian vessel ligation in gynecologic procedures may damage the ureter vas deferens (in males) Blood supply consists of branches from renal arteries (most proximal) testicular arteries (in men) and ovarian arteries (in women) the descending aorta internal iliac arteries superior vesical arteries uterine arteries (in women) vaginal arteries (in women) and inferior vesical arteries (in men) (most distal) Urinary Bladder A temporary reservoir of urine Innervation parasympathetic fibers conveyed from the sacral spinal cord via the pelvic splanchnic nerves and inferior hypogastric plexus provide motor innervation to the detrusor muscle inhibits contraction of the internal urethral sphincter in men sympathetic fibers conveyed from the lower thoracic and upper lumbar spinal cord via the hypogastric plexus and nerves promotes contraction of the internal urethral sphincter Urethra A muscular tube that allows urine to travel from the urinary bladder to the external world the urethra also provides an exit path for semen the female urethra is much shorter (~4 cm) than the male urethra (~18-22 cm) this is a reason as to why women are more prone to developing urinary tract infections than men Urethral injury posterior urethra the weakest point is in the bulbomembranous junction prone to injury in pelvic fractures (e.g., from a motor vehicle accident) can result in urine or blood being found in the retropubic space anterior urethra injury to the anterior urethra can result from straddle injuries instrumentation pelvic fracture (in conjunction) direct blow injury can result in urine or blood being found in the deep fascia of Buck superficial perineal space when the deep fascia of Buck is torn