"Normally a person with an injury on the bottom of their foot, such as a blister, will change the way they walk. Your gait will alter because you are going to protect that blistered spot until it heals up," says Joseph LeMaster, MD, an assistant professor at the University of Missouri–Columbia School of Medicine.
"People with a loss of sensation don't do that. They will just walk right on top of that blister as though it wasn't there. It can burst, become infected, and turn into what we call a foot ulcer," he says. "That ulceration can go right down to the bone and become an avenue for infection into the whole foot. That's what leads to amputations."
Foot injuries are the most common cause of hospitalizations
About 15% of all diabetics will develop a foot ulcer at some point and up to 24% of people with a foot ulcer need an amputation. You're at extra-high risk if you're black, Hispanic, or Native American. These minority populations are two to three times more likely to have diabetes than non-Hispanic whites, and their rates of amputations are higher.
About a year ago, Dr. Armstrong treated a 59-year-old man with type 2 diabetes who had been working out at a local health club; 12 hours later, he discovered a screw from a piece of gym equipment lodged in his foot.
"This isn't a dummy. He's a sweetheart of a guy," says Dr. Armstrong. "It's just that he doesn't have the gift of pain, and that's what's so profound." Ultimately the man's toes were amputated, but he is able to walk and work out with close monitoring, Dr. Armstrong said.