We hear you laughing, but it's actually a serious health condition.

For most guys, a long-lasting erection might not sound like such a bad thing. But having a hard-on for more than four hours is actually a cause for concern. That was the case for one man, who ended up in the hospital after a moped crash caused him to have a nine-day erection.

An article published in Case Reports in Urology in April 2019 states that last year, a UK man bruised his perineum—the space between his scrotum and anus—after he fell off of his moped. The injury, referred to as a bilateral arteriovenous fistulae, triggered a constant flow of blood to his penis, which resulted in a “Grade IV erection.” This is the highest level of erection on the Erection Hardness Score scale. (Yes, there is such a thing.)

Priapism is the medical term for an erection that lasts longer than four hours and is unrelated to sexual activity. The man in this case study had high flow priapism, meaning blood would not stop flowing into his penis. Amazingly, this caused him only slight discomfort while walking, according to the case report. Low-flow priapism is the much more painful kind; this occurs when blood flows into the penis but is unable to flow out.

Priapism is not all that common, but it happens more often than you might think. The condition sent approximately 8,700 men to emergency rooms nationwide over a three-year time span, according to a study published in the Journal of Sexual Medicine.

Typically, high-flow priapism is treated by applying ice packs to the penis, mechanical decompression on the affected blood vessels, or an injection of chemicals to help relieve the patient of his erection. In this case, however, doctors decided "timely intervention [needed] to be considered to avoid the potential risk of erectile dysfunction in the long term."

While some men with priapism can develop erection issues or even have part of their penis amputated, the moped man ended up just fine. Doctors inserted gel-like foam and a microcoil into his penis through a catheter, finally restricting the blood flow. The man’s penis went back to normal and is still fully functioning a year later, the case report sums up.

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