Fistulas are openings through which urine flows apart from the urinary meatus. They can appear anywhere along the shaft of the penis, on the lower abdominal wall, even on the perineum behind the testicles. Fistula can occur immediately after surgery when a wound isn’t completely healed, and these can sometimes heal on their own. Persistent fistula usually result from a previous surgical wound breaking down under the force of urine wearing away at the tissue until a channel works it way to the outside of the skin and creates a leak. Besides making urination messy, these leaks also increase the possibility of infection. Some fistula can remain for years without major complications, but eventually will require surgical repair. If the leak is inside the penis and breaks into the spongy bodies involved in erection, that kind of leak is called “extravasation” and is very painful, requiring immediate medical attention.