Stress fractures are sneaky. Unlike a regular fracture, which wastes no time making itself known (the bone is broken immediately on impact), a stress fracture takes its time, developing gradually over a period of days.
Even then, it doesn’t reveal itself on X-rays. That’s how tiny and microscopic the break, or crack, in the bone is — compared with a regular fracture, which is more obvious on imaging tests.
Stress fractures occupy one end of the spectrum in a category of what experts call “stress-related injuries,” which happen when too much strain is placed on a particular part of the body, explains Murphy P. Martin III, M.D., assistant professor of orthopedic surgery at Tulane University School of Medicine. When that body part is the bone, the added stress can result in anything from a bruise to a small break, also known as a stress fracture.
5 Warning Signs of a Stress Fracture
- Pain that gets worse during physical activity
- Pain once you stop physical activity
- Pain at rest
It doesn’t take much to wind up with one. “You don’t have to be a walker who’s suddenly training for a marathon” to experience a stress fracture, says Anish R. Kadakia, M.D., professor of orthopedic surgery at Northwestern University Feinberg School of Medicine. Even a small change can do it, especially if the stressed body part doesn’t have time to heal.
“If you’re a 2-mile walker and now you’re going 2½ miles, that sudden increase in activity can absolutely be a cause for a stress fracture,” Kadakia says.
Who’s at risk of a stress fracture?
If you know a little about stress fractures — namely that they’re common among competitive athletes and people who serve in the military — you may think you’re in the clear. Turns out, people over age 50 are also at particular risk for stress fractures. The culprit: dwindling bone mass. As bone mass decreases, the chances of experiencing a stress fracture increase.
“As we age, we all lose bone stock,” Kadakia says. “By age 30, you’ve deposited all the bone you’re ever going to deposit. After that, it’s a slow decrease.”