Stress Fracture Vs Tendonitis – How To Tell The Difference


Tendonitis is one of the most common injuries when it comes to running, and it occurs most often in the Achilles. About 80% of running injuries are caused by repetitive force on the foot or lower extremities, but how do you know what exactly is causing your foot pain?

Understanding how to tell the difference between a stress fracture vs tendonitis can help you to treat the injury correctly and reduce the amount of time it takes to heal.

On the other hand, treating a more severe injury as a light one may end up making it worse and can leave you sidelined for weeks or months, or even needing surgery to repair the damage.

Here’s all you need to know about these two conditions and how to figure out which one you have so you can treat it appropriately.

What Is Tendonitis?

As its name suggests, tendonitis is an injury of the tendon – most often, for runners, the Achilles tendon in the heel. But it usually affects much more than just the tendon. The soft tissues around the tendon, as well as any nearby ligaments, are often affected too.

This happens because the tendon becomes inflamed, which causes inflammation and pain in the surrounding areas too. Inflammation is often a result of repeated, constant force on pressure on the foot.

This kind of repetitive stress could be something like jumping or kicking if you play those kinds of sports. Or, it could simply be running or walking without proper support for your feet.

Excessive repetitive motion on the same part of the body can lead to this inflammation of the tendons involved. It’s worth noting that tendonitis doesn’t only occur in the Achilles.

Anywhere there’s a tendon and movement, it could happen!

For example, tennis elbow is a form of tendonitis. It can happen in the foot, elbow, wrist, knee, shoulder, and even the thumb joint.

What Are Stress Fractures?

A fracture is different from a break in a bone. Stress fractures are small cracks that occur in the bone’s surfaces. This may not sound too bad, but it can be painful and if left untreated, may develop into much more severe cracks or breaks.

Stress fractures are most commonly found in bones in the foot and the lower leg. This is because they’re weight-bearing, so they take on more than the full body weight every time you step.

Whether you’re taking a leisurely walk or sprinting, standing for long hours, or doing sports that involve jumping, stress fractures can occur as a result of repeated “trauma” to those bones.

It’s also important to note that both tendonitis and stress fractures can happen to anyone, not just athletes!

Although athletes may be more susceptible because of their active, often high-impact lifestyle, those who do no sports at all may be equally at risk depending on their lifestyles and jobs.

What Are the Symptoms of Tendonitis?

Tendonitis usually shows up as a dull but lingering ache in a joint or a limb. It feels worse when the affected area is moved, and it may be accompanied by tenderness to the touch and a bit of swelling.

It may be relieved by compression gear or a tendonitis-specific “brace” to place pressure directly on the painful area. Tendonitis also responds well to RICE treatment.

What Are Symptoms of Stress Fractures?

Stress fractures don’t respond to RICE treatment. If you’ve got a deep, aching pain in a limb or at a joint that doesn’t ease up when you rest it, it could be a stress fracture. A telltale sign is pain in the night when your affected limb is not moving or bearing weight at all.

The pain will most likely increase noticeably on impact; for example, when walking, running, or even just bumping the limb accidentally.

You’ll usually be able to point to a specific place along the bone where the pain is bad. There may also be weakness of the limb or even things like tingling or numbness.

How Can a Stress Fracture Be Diagnosed?

It can be difficult to diagnose a stress fracture, as it’s not as glaring as a broken bone. Because there are so many different reasons behind pain, it could be mistaken for something else, especially if you have a high pain threshold.

Pain in the shin could be shin splints, or pain in the foot could be metatarsalgia. It’s made harder by the fact that sometimes, an x-ray won’t even pick up small cracks in the bone.

Typically, if a doctor or physio suspects that you have a stress fracture, they’ll do a range of different tests to get as close to a definitive diagnosis as possible. Usually, this involves an x-ray, an MRI, and any other tests (depending on the location of the pain) that may help to rule out other things.

What Is the Treatment for Tendonitis?

Tendonitis responds pretty well to the RICE principle. As with all foot or leg injuries, the best start is to rest the affected area. Give your sports a break (as hard as that may be!) so your tendon has time and space to heal.

You can apply ice a few times a day for up to 20 minutes at a time. Make sure to wrap the ice or ice pack in a cloth or towel before placing it on the skin.

Compression gear is excellent supplemental treatment for tendonitis. Socks come in handy for anything on the calf and ankle, and you can buy compression items specific to tennis elbow or other areas.

If the swelling persists, elevating the affected area above the heart can help the excess fluid in the limb to drain, which will relieve some pressure.

Once you’ve rested the limb for a few days, begin gently stretching it to make sure it can move through its full range of motion.

From here, you can start doing light, easy exercises. If you’re working with a physio, they’ll provide exercises for you that are designed to progressively increase to strengthen your foot back up again.

What Is the Treatment for Stress Fractures?

Unfortunately, there’s no real fix for these little cracks in the bone. You can’t splint them or put them in a cast. But you can ease pressure on the foot by resting and icing it.

If you continue with your activity, you may end up causing worse cracks in the bone, which could require much more time off the road, court, or field, and even require surgery to fix.

The doctor may also recommend icing your area of pain regularly throughout the day, to supplement the rest.

You should be very careful about reintroducing activity. While you’re healing, you can take part in low-impact recovery activities, like swimming or cycling. Introduce your running, jumping, and high-impact activities slowly, a little at a time.

You also shouldn’t go right back into your previous volume of training. Run less frequently, less far, and less intensely until you’ve built up the strength again.

How Can You Prevent Tendonitis?

Tendonitis can happen to anyone, but there are a few things you can start incorporating to reduce the chance of getting it.


Supplementing your running with low-impact cross-training activities like cycling or swimming can make a huge difference. You’ll still be getting your exercise in, but you’ll be working different muscles and giving your feet a bit of a break.

Just swapping out a workout or two per week can make a big difference. It’s much harder for that tendon to be overworked when it’s doing less work! At the same time, you aren’t skipping training. You’re just developing a more well-balanced training routine.

Strength Training

Strength training has many benefits, including increasing bone mass and building muscle to support your joints. If you incorporate strength training as a form of cross-training, you’ll need to make sure you’re involving the full body.

But concentrate particularly on the area of the body in which the tendonitis occurs. It may be possible to build some muscle around the joint or tendon that can help to support and stabilize it, reducing the chance of inflammation.

Lower Your Intensity, Volume, or Distance

Too many miles, pushing too hard, or running too often can all have a detrimental effect when it comes to tendonitis. If you’re planning on increasing your mileage, do it slowly – 5% to 10% every few weeks is acceptable.

But if your sore spot is beginning to feel niggly, it’s a good idea to lower your training volume. Either reduce the number of miles you’re running or walking in a day or reduce the number of times you’re running per week.

How Can You Prevent Stress Fractures?

Nobody wants to be sidelined for months due to a stress fracture! Here are some steps you can take to reduce your chances of suffering from these painful bone cracks.

Make Changes Slowly

Whether you’re starting a new sport, increasing your training intensity, or adding miles to your daily run, do it slowly and carefully.

Increase mileage by 5 to 10% at a time, and it’s a good idea to give it a few weeks or even months for your body to get used to the new number before increasing again.

If you have a goal you’re aiming at, you can stick to a 10% increase per week, but that’s the quickest we recommend increasing.

Use Proper Footwear

Incorrect footwear can keep your feet in the wrong position, leading to unnecessary stress on parts of your foot. This can lead to both tendonitis and stress fractures, so choosing a shoe that fits your foot perfectly is highly important.

If you roll your feet inwards when you walk or run (overpronate), your foot goes out of alignment very quickly. You’ll need a shoe with extra support in the arch area to prevent this from happening. These are called stability shoes, and they’re easy to find.

If you don’t roll your foot, you can get away with a neutral shoe. But make sure it feels snug and supports your foot properly in the arch, heel, and that there’s plenty of room for your toes to spread out.

It’s also important to choose the right shoes for whatever activity you’ll be doing. Running shoes for running, casual shoes or sneakers for around the house, cross-training shoes for other forms of exercise, and so on.

If you find that your current shoes aren’t as supportive as you’d like, you may choose to invest in an insole before buying a whole new pair of shoes.


Adding those extra low-impact exercises to your weekly fitness routine helps immensely. It takes some strain off of your muscles and gives them all a chance to rest a bit before being worked out again.

You’ll also be building strength, so your joints will be better supported. Your posture is likely to improve too, which helps to keep everything in alignment.

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Shanna is a writer who runs... And cycles, jumps rope, and lifts weights. She lives in beautiful South Africa and enjoys sharing her knowledge and experience with other avid athletes.