Where Are You Most Likely to Get a Stress Fracture? Research to Help You Catch Potential Stress Fractures Early
A stress fracture is one of the most feared running injuries. With a virtually guaranteed six or eight-week layoff from running, the prospect of sustaining one is unsettling even to veteran runners who have dealt with other injuries. Additionally, the fact that it’s a bone injury—something we usually associate with hard falls or other traumatic incidents—gives a stress fracture an additional tone of seriousness.
Intuitively, the bone doesn’t seem like it should be injured from something as basic and “normal” as running. But, as many runners discover every year, stress fractures are a reality. Progressive stress on the bones, either from impact with the ground or the “active force” that occurs when you push off the ground, can surpass your bones’ structural integrity, leading to a stress fracture.
As such, being aware of where stress fractures occur and how common the various locations are can help you catch one early, potentially sparing yourself weeks of time off from running, or even prevent one entirely.
The science behind where runners get stress fractures
While, in theory, any bone in the lower body can get a stress fracture, in practice they are much more common in some locations than in others. This likely has to do with some universal biomechanical principles that apply to running, though these are poorly understood as of right now. One simple example might be the tibia and fibula. These two bones make up your lower leg, but while the tibia is much thicker than the fibula, it is much more likely to sustain a stress fracture. This is probably because it bears most of the weight while running, the fibula being relegated to a “support” role. To get a better picture of where stress fractures occur, we’ll turn to the scientific literature.
A cursory review of the literature reveals that stress fractures account for around 20% of all injuries in runners.
While this is substantial, it’s nevertheless difficult to conduct large studies on the location of stress fractures among all types of runners. For this reason, studies tend to focus on groups of athletes that are at a higher risk for stress fractures. This is the case with both studies we’ll look at today.
Fractures In Focus
The first is a 2003 paper by Elizabeth Arendt and colleagues at the University of Minnesota. In this study, ten years’ worth of college athletes were tracked and the patterns of stress fractures were analyzed, both by sport and by gender.
- Like many sports injuries, stress fractures were more common in women, with about three female athletes getting a stress fracture for every two male athletes.
- Distance runners, who accounted for the largest proportion of the athletes with a stress fracture, tended to suffer from stress fractures to the tibia, femur, fibula, metatarsals, and navicular, with the tibia being about twice as common as the others. No stress fractures to the pelvis or spine were reported.
Unfortunately (for our purposes at least), Arendt et al.’s study only counted 23 stress fractures in runners. While this is fantastic for the athletes in those ten years, our ability to predict where stress fractures occur is somewhat limited by this relatively small number.
An earlier study by Gray Barrow and Subrata Saha at Louisiana State University addresses this issue.
Using surveys mailed to female varsity distance runners at colleges and universities across the United States, Barrow and Saha collected information on the incidence and location of stress fractures in the sampled athletes. Since the population studied (female distance runners) were at a significantly higher risk for stress fractures, and given that women who had suffered a stress fracture were probably more inclined to respond to the survey, it is no surprise that 89 of the 241 women who responded had suffered at least one stress fracture from running.
In total, 140 stress fractures had occurred in the 89 subjects.
The tibia accounted for 64% of these, followed by the metatarsals at 21%, the fibula at 9%, and the pelvis, calcaneous (heel bone), & tarsal (midfoot, including navicular) bones at 3%, 1%, and 1%, respectively.
Additionally, the number of respondents allowed Barrow and Saha to break down the specific locations of stress fractures on the tibia, fibula, and metatarsal bones.
- On the tibia, half of the stress fractures occurred in the distal third of the tibia, meaning somewhere along the first third of the bone’s length, starting from the ankle. The other half were divided about evenly between the middle third and top third of the tibia.
- Among the metatarsals, the long bones that make up the midsection of your foot, the second metatarsal (the one corresponding to your “index toe,” or the one next to your big toe) accounted for fully half of all metatarsal stress fractures. Another quarter occurred in the third metatarsal, with the fourth and first metatarsals accounting for 14 and 10%. No runners in this study suffered a fifth metatarsal stress fracture.
What you can take from this research
Any persistent running injury deserves to be seen by a doctor. However, if runners were to run (no pun intended) to the doctor every time they felt a little niggle, we’d be broke and doctors and health insurance companies would be lining their pockets. As such, we can use this research to better identify what pain might be a serious stress fracture and avoid costly breaks in training and trips to the doctor.
- As we’ve learned from the research, runners—especially female runners—should be particularly attuned to their tibia and metatarsal bones, as these are the most common bones to suffer a stress fracture.
- In the tibia, stress fractures can occur anywhere, but are most common in the lowest third of the bone. In the metatarsals, the second and third metatarsals account for three-quarters of stress fractures.
- While stress fractures to the femur, pelvis, and navicular are particularly worrisome due to their reputation for poor healing, they are fortunately exceedingly rare.
When it comes to preventing stress fractures, there’s no perfect recipe, but as we’ve seen in other articles, strategies like increasing your stride frequency, being smart about your training, and paying attention to your diet and overall health are evidence-based methods to reduce your risk.