Trigone of the bladder This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Trigone_of_the_bladder".
The trigone is a smooth triangular region of the internal urinary bladder formed by the two ureteral orifices and the internal urethral orifice.
The area is very sensitive to expansion and once stretched to a certain degree, the urinary bladder signals the brain of its need to empty. The signals become stronger as the bladder continues to fill.
Clinically important because infections (trigonitis) tend to persist in this region.
Urethral sphincters (External sphincter muscle of male urethra, External sphincter muscle of female urethra, Internal sphincter muscle of urethra)
