|Species||Sex||Histologic studies||Functional studies||References|
Striated muscle is thin and circular, prominently occupying the middle urethra.|
Type II fibers are predominant.
Urine flow disrupted by partial/full closure of urethra|
Lower max flow rate and shorter micturition time
Praud et al. |
Lim et al. 
Buffini et al. 
Biérinx et al. 
Streng et al. 
Striated muscle forms a thick layer.|
100% type II fibers in the upper urethra. Luminal muscle contains a mix of type I and II fibers.
|Human||Female||Striated muscle extends the length of the urethra and is composed of predominantly type I slow twitch fibers (87% vs. 13%).||
Benoit et al. |
Ho et al. 
|Male||Striated muscle extends from the membranous urethra over the prostate and has a mixture of both slow and fast twitch fibers (65% vs. 35%).|