There is no bone in the penis, yet penises can break. Yes, you read that correctly: penises can break. Although a willy won’t break in the same way as a femur or a wrist, they can be fractured while a man has an erection. The damage, if not taken care of immediately, can be extensive.

Penile fracturing can happen when one of the two corpus cavernosum — cylinders within the shaft of the penis, which are surrounded by muscles — are bent while the penis is erect, i.e. encourged with blood. The bending, which needs to be pretty forceful, can rupture the lining and connective tissue (tunica albuginea), around those corpus cavernosum cylinders and the result is a very painful  fractured penis.

The good news is that fractured penises aren’t all that common Alas, they still happen more than any penis-wielding person and the partner who loves them, would like. But penises fractures can also be prevented: basically, avoid putting penises in precarious situations as much as possible.

Here’s what you need to know to keep your own penis (or one one belonging to someone you love) out of harm’s way!

Be Safe During These Three Causes of Penile Fracture:

1. Cowgirl position during sex. Recently, the journal Advances in Urology found that about 50% of penile fractures can be directly attributed to the cowgirl position (woman on top) during sex. In fact scientists have concluded that this is the most dangerous sex position out there! According to the study, the reason a woman being on top can do such damage is a mixture of both the weight of her body coming down on the erect penis and how she lands on it:

“Our hypothesis is that when a woman is on top she usually controls the movement with her entire body weight landing on the erect penis and not being able to interrupt it when the penis suffers a wrong way penetration, because the harm is usually minor in women with no pain, but major in the penis.”

The same study also found that the runner-up sex positions when it comes to causing penile fractures are doggy-style at 29%, and missionary (man on top) at 21%.

The Los Angeles Times notes that younger men are most at risk for penile fractures in general due to “the firmness of their erections and athleticism of their activities.”

2. Masturbation. Sorry to freak you out, dudes, but avoiding cowgirl-style won’t put you in the clear: you can also break your penis from jerking off. Yes, vigorous, excessive, and aggressive maturbation (is there any other way?) can also result in penile fracture. While masturbation is indeed a healthy part of human sexuality and even aids in having a healthy sex life with your partner, the reality is that doing it too much and too hard can end in not just a penile fracture, but skin problems of the penis, too. Eeek.

3. Taqaandan. Although the practice of Taqaandan isn’t as common in the West as it is in the Middle East, it’s still prevalent enough that it’s worth mentioning. As the LA Times reports, Taqaandan comes from the Kurdish word meaning “to click.” The practice is popping the head of an erect penis in the same way one would crack their knuckles. Although there doesn’t seem to be any sexual benefit from the practice, apparently it does supply the similar relief that comes with knuckle cracking. In countries like Iran it has become somewhat of a health issue, because it does result in penile fractures so often. So, yeah, don’t do that.

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Signs of Penile Fracture (Although We Are Pretty Sure It Will Be Obvious)

1. The scary “cracking” sound. The most terrifying part of fracturing the penis is the “audible cracking sound,” says the Mayo Clinic.  Sometimes it’s referred to a popping sound, too. Either way, it’s a loud enough noise that if you’re alone, you’ll definitely hear it, and if you’re mid-intercourse with your partner, then you’ll both hear it — and you’ll probably both freak the eff out.

2. Swelling and discoloration. After that good ol’ “POP!” the penis slips into flaccidity and turns blue and purple almost immediately, as the blood that is usually contained in the corpus cavernosum escapes (because you’ve snapped that cylinder), and rushes to the surface. At this time, the penis can also become swollen.

3. Blood in the urine. This sounds really scary, but when you think it trhough, it’s quite logical: If the fractured penis has also damaged the urethrathen the dead giveaway for that is blood in the urine. Blood on the opening of the penis may also be visible. Anywhere from 10 to 30 % of penile fractures will include urethra damage. (We are going to go ahead and advise that ANY time you see blood in the urine, male or female, you should see a doctor immediately.)

4. Pain. The pain of a fractured penis involved has been called “severe” and “traumatic.” To boot, there’s no telling how long it will last. One word: Ouch.

But despite this pain and the all the other signs that something is very wrong with their penis, some men, being too embarrassed about the condition, don’t seek the immediate medical attention that they should. Guys, this is not the time to be ashamed! In some cases, men have waited a whopping six hours suffering before they finally went to see a doctor.

READ MORE: Why Penis Pictures Aren’t Pretty

Treatment for Penile Fracture:

1. Conservative treatment. Depending on the extent of the damage done, a doctor might choose what’s called “conservative treatment,” which includes cold compresses, as well as anti-inflammatory drugs, and other meds that will help in reperfusion, AKA restoring blood flow to a tissue or organ

Possible complications include permanent curvature of the penis, abscesses, as well as Peyronie’s disease, in which scar tissues is formed “in a disorganized manner,” contributing to penile deformity and dysfunctions with erections, including life-long erectile pain.

2. Surgical repair. Surgical repair, on the other hand, really gets in there, literally, and fixes everything right up. Although invasive, it corrects the damaged corpus cavernosum and tunica albuginea, and repairs any injury that was made to the urethra.

Ultimately, if any kind of pain is experienced during intercourse or masturbation, it’s best if you and your partner take a break before something, well, breaks. A penile fracture isn’t the end of the world, but it will definitely put the man out of commission for a bit and put your sex life on hold. No one wants that. So play safely and stay out of the emergency room.

READ MORE: 5 Sex Positions to Practically Guarantee an Orgasm