A stress fracture occurs when your bone literally cracks because of repeated stress. Based on that definition, you’d think the symptoms of this injury would be super obvious.
Unfortunately, stress fractures aren’t that straightforward, which is why runners overlook the signs of them “all the time,” Chris Johnson, PT, a physical therapist and performance coach in Seattle, tells Runner’s World.
Doctors can gloss over them, too. “Even in medicine, we probably miss it sometimes or don't think about it as much when maybe we should,” Todd McGrath, MD, a sports medicine physician at Hospital for Special Surgery in New York City, tells Runner’s World.
Part of the problem is that stress fractures can be mistaken for a bunch of other common, less serious running injuries, including shin splints, IT band irritation, hip flexor tendinitis, SI joint pain, and generalized lower back or foot pain. But there are red flags that help distinguish a stress fracture from other injuries. And because it’s important to know if you’re at risk of a fracture, we’ve rounded them up below.
Read on to learn why it’s so important to distinguish stress fractures from other injuries, the tell-tale signs you may be dealing with one, and what to do next to kick-start your recovery.
Why It’s Important to Differentiate Stress Fractures From Other Injuries
A stress fracture is a type of bone stress injury (BSI). A BSI is basically when a bone cannot withstand a load or force placed on it, and, as a result, experiences a structural failure, as Runner’s World previously reported. Stress fractures are the most serious type of BSI; they usually begin as stress reactions, which is when the bone weakens and swells, but doesn’t actually crack.
Having any type of BSI isn’t great, but if you catch a stress reaction early and take the proper steps to heal it, you can prevent it from progressing to a stress fracture. “Ideally, you want to catch it as a stress reaction versus a stress fracture,” Nicole Haas, PT, DPT, a physical therapist in Boulder, Colorado, tells Runner’s World.
Johnson agrees: “The most important aspect about these bone stress injuries is early identification.”
Basically, treating a BSI early “shortens the duration of the treatment, as well as prevents a lot of excess treatment [such as surgery],” McGrath says.
LEARN HOW TO PREVENT STRESS FRACTURES HERE
Of course, there are a lot of things runners “love to ignore” with the hope that they’ll just go away on their own, Haas says. And sometimes, those little aches and pains do dissipate with time, even stress reactions that show no symptoms (as per research). But that’s not the case with stress fractures or symptomatic stress reactions. When you have a symptomatic BSI, you need to stop running and allow the bone time to heal. If you continue placing load on it, you will likely worsen the injury.
This is a different approach from other running injuries—like IT band syndrome, shin splints, or Achilles tendinitis, for example—where it’s often feasible to continue running, as long as you modify your training, like cutting back on intensity or mileage and adding in strength training.
As for how long it takes to heal a BSI, recovery can last anywhere from six weeks to six months, Johnson says. He cautions that healing time can be even longer if there are compounding factors, like low energy availability (not eating enough to support your body’s daily needs and training), hormonal or menstrual dysfunction, low bone mineral density, inadequate nutrition, or a history of prior bone stress injuries.
Also key: The grade of the BSI and the specific area make a big difference in healing timelines, Johnson says. Runners with low-grade (grade 1 and 2) bone stress injuries at low-risk sites—for example, the posteromedial tibia (back or inner part of the shin), metatarsals 2 to 4 (middle toe bones), and fibula (calf bone)—tend to return to training sooner.
Runners with higher-grade injuries (grade 3 and 4), or injuries at high-risk sites like the femoral neck (top of the thigh bone, just below the ball of the hip joint), anterior tibia (front part of the shin bone), or navicular (bone in your midfoot), take much longer, he says.
How to Spot a Stress Fracture
Typically, there isn’t just one symptom that points to a stress fracture, but instead it’s a collection of signs. Here are some to watch out for, according to the three experts we interviewed.
Pain in One Spot
Isolated bony tenderness, meaning a specific part of your bone hurts when you press on it, is a red flag. “Shin splints often hurt a little bit up and down the entire length of the shin, but if it’s a focal point on the tibia [shin bone] that really hurts, we worry a lot about a stress fracture in that area,” McGrath says.
You can also think of it as pain on your leg that’s concentrated to an area that’s five centimeters or smaller, which equates to the size of a ChapStick, house key, or AA battery, Johnson says.
Another example: Having anterior groin pain while doing higher-volume training “is always a little bit of a red flag,” McGrath says.
In Johnson’s experience, runners who think they have a quad strain, hip flexor strain, or sacroiliac joint pain (where the lower spine meets the pelvis) are typically dealing with a BSI instead in their femoral shaft (long, central section of thigh bone), femoral neck (top of the thigh bone, just below the ball of the hip joint), or sacral bone (at base of lumbar spine), respectively.
You’ll also typically see swelling or feel tenderness around the pain point.
Pain Following Training Increases
Pain that cropped up a few weeks after a big jump in training volume, which McGrath defines as a weekly increase of 30 percent or more, can point to a stress fracture.
Pain That Progresses
Stress fracture pain gradually progresses with time. For example, it may start as mild discomfort at the end of your runs that morphs into pain that comes on earlier in your runs and/or changes the way you run, and eventually escalates to pain with walking and then at rest.
It also won’t improve with movement, like you’ll see with mild cases of patellar tendinopathy, IT band syndrome, and plantar fasciitis. And if it used to get better with activity, and no longer does, that’s a red flag to pay attention to.
Finally, single-leg hopping, specifically, can also worsen pain.
Pain Combined With Illness/Injury History
Pain combined with a history of Relative Energy Deficiency in Sport (RED-S), or any current signs and symptoms of RED-S. (Formerly known as the female athlete triad, RED-S is a condition of low energy availability caused by chronic under-fueling, and it can be a contributing factor to BSIs.)
A prior history of bone stress injury, along with pain, could also signal a stress fracture.
Hard-to-Pinpoint Pain
Pain that’s vague and not associated with one specific sudden movement typically signals a stress fracture. It may feel unfamiliar, disconcerting, or distracting, Johnson says.
Severe Pain
Pain that’s so intense you feel like you need to take pain medication to be able to run.
Related side note: Johnson doesn’t recommend taking NSAIDs while running, a stance supported by other experts and research. One reason: This class of medication interferes with a bone’s ability to heal because it retards collagen synthesis, which is what bones and tendons are primarily composed of, Johnson explains.
What to Do if You Suspect You Have a Stress Fracture
Stop running, McGrath says. For most people, it’s probably okay to continue to walk if doing so isn’t too painful, he adds, but you’ll want to really limit how much overall impact activity you’re doing until you can get in to see a doctor or PT. They can evaluate you and advise on next steps, including whether imaging—such as an x-ray or MRI—is recommended to confirm a diagnosis.
Jenny is a Boulder, Colorado-based health and fitness journalist. She’s been freelancing for Runner’s World since 2015 and especially loves to write human interest profiles, in-depth service pieces and stories that explore the intersection of exercise and mental health. Her work has also been published by SELF, Men’s Journal, and Condé Nast Traveler, among other outlets. When she’s not running or writing, Jenny enjoys coaching youth swimming, rereading Harry Potter, and buying too many houseplants.
