... in response to Re: Viagra overdose? [n/t], posted by Pete E on Jan 17, 2005Penile fracture is the traumatic rupture of the corpus cavernosum. Traumatic rupture of the penis is relatively uncommon and is considered a urologic emergency.
Sudden blunt trauma or abrupt lateral bending of the penis in an erect state can break the markedly thinned and stiff tunica albuginea, resulting in a fractured penis. One or both corpora may be involved, and concomitant injury to the penile urethra may occur. Urethral trauma is more common when both corpora cavernosa are injured.
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Frequency: To date, the number of reported cases in the published literature is estimated to be fewer than 300. Trauma during sexual relations is reported to be responsible for approximately one third of all cases; the female-dominant position is most commonly reported. The incidence of concomitant urethral injury in reported cases is 10-38%.
Etiology: In the Western Hemisphere, the injury most commonly occurs during sexual intercourse when the penis slips out of the vagina and strikes the perineum or the pubic symphysis. Other potential causes include industrial accidents, masturbation, gunshot wounds, or any other mechanical trauma that causes forcible breaking of an erect penis.
In Middle Eastern countries, the injury more commonly occurs secondary to penile manipulation to achieve detumescence. Additional rare etiologies include turning over in bed, a direct blow, forced bending, or hastily removing or applying clothing when the penis is erect.
http://www.emedicine.com/med/byname/penile-fracture-and-trauma.htm