membranous urethra

The membranous urethra is a short section that goes through the urethral sphincter.

Its innermost fibers form a continuous circular investment for the membranous urethra.

Positive margins of the membranous urethra on frozen section taken at the time of cystoprostatectomy.

Amussat's fold: abnormal folds of the membranous urethra at the level of the seminal colliculus.

Farther along the urethra is a sphincter of skeletal muscle, the sphincter of the membranous urethra (external urethral sphincter).

The external sphincter muscle of urethra (sphincter urethrae): located at the bladder's distal inferior end in females and inferior to the prostate (at the level of the membranous urethra) in males is a secondary sphincter to control the flow of urine through the urethra.