This process doesn't take place over a few weeks, either. In most cases, it lasts for an entire year, and it can even strike two toes simultaneously. Sure changes the stakes of "This Little Piggy," doesn't it?
Related: 6 Freaky Things Your Body Does (Explained By Science)
A Woman's Eyelid Grew Bones
In 2009, a cosmetic surgeon in LA was approached by a woman who had recently undergone a radical new treatment in which stem cells were injected into the area of her face surrounding the eyes, all in the service of reducing signs of aging. The surgery had gone well, but soon enough, she couldn't open her right eye without considerable amounts of pain and a weird clicking sound coming from her face. His interest piqued, the surgeon opened her up, and after six hours of digging around, began pulling bits of bone from inside her right eyelid.
As it turns out, that "radical" procedure came with an unspoken side effect. The stem cells that had been injected into her face were designed to grow into fresh new lemon-scented tissue. During the surgery, however, she'd also received an injection that contained quantities of calcium hydroxylapatite, a mineral that in certain circumstances can "reprogram" stem cells to turn into bone. That clicking noise she heard every time she opened her eye? That was the bones that'd grown in her eyelid grinding against one another.
The surgeon was able to remove the bones, but there's no getting around the fact that her face is now a ticking time bomb that could one day turn to bone again -- a thought that, ironically, is probably making her age faster than ever.