Peroneal Tendonitis – Symptoms, Causes, and Treatments

Foot and lower leg pain can affect your everyday life. It’s hard to go about your day without using those parts of your body, so it’s essential that you find out the cause and treat the pain as soon as possible.

Peroneal tendonitis is often misdiagnosed, meaning any treatment you do may not have the desired effect. If you thought you had Achilles tendonitis but it isn’t responding to the usual treatment, then you may have peroneal tendonitis instead.

In this article, we’ll have a look at the condition, its symptoms, its causes, and how you can treat it.

What Is Peroneal Tendonitis?

Peroneal tendonitis is when the thick tendons on the outside of the lower leg become inflamed and painful. These tendons run from the lower leg, down behind the ankle, and then split and reattach at different points on the foot.

The two tendons—peroneus longus and peroneus brevis—are thick, strong strips of connective tissue.

Peroneus brevis reattaches about halfway to the baby toe on the outside of the foot. Peroneus longus runs underneath the foot, across the arch, and attaches near the inside of the arch on the opposite side.

Pain and inflammation can also occur in one tendon or both the peroneal tendons. Meaning the pain from peroneal tendonitis can occur in a variety of different places across the foot.

It can also occur on both sides or just one side of your lower legs or feet.

What Do Peroneal Tendons Do?

The two peroneal tendons are responsible for stabilizing the foot and ankle. They provide support for both the outer side of the foot and some support under the arch.

They help to facilitate inward and outward movement of the ankle, and protect the foot from twisting injuries like sprains.

What’s the Difference Between Peroneal Tendonitis & Peroneal Tendinopathy?

Peroneal tendonitis is the acute form of inflammation in the peroneal tendons. It becomes peroneal tendinopathy when the condition becomes chronic.

So technically, the two conditions are the same. However, the terms are often used interchangeably to describe pain and inflammation in the peroneal tendons.

Symptoms of Peroneal Tendonitis

The symptoms of peroneal tendonitis can present in a similar way to those of Achilles tendonitis. However, there are small differences that can indicate the difference between the two.

Here are the symptoms of peroneal tendonitis you should look out for:

Pain Around the Outer Ankle Joint

You will notice an aching sensation or a sharp pain in, around, or near the outer ankle bone on the affected foot. This is one of the biggest differences between Achilles and peroneal tendonitis.

This pain will get worse when you turn your foot inward or outward. It should get better with rest, like standing without moving your foot.

Pain On the Outside Edge of the Foot

One of the peroneal tendons connects to the foot about halfway to the toe on the outer edge. If this is the tendon that’s inflamed, it can cause pain on the outer edge of your foot.

Pain Underneath Your Foot

As your one peroneal tendon runs underneath your foot, you may feel pain under your foot, just in front of the heel into the arch. In some cases, this pain may be mistaken for plantar fasciitis, so it’s important to consider other symptoms as well.

Swelling At the Back/Side of the Ankle

You may notice swelling in the same area and pain in the outer ankle. This is a result of the inflammation in the tendon running behind the ankle.

There may also be swelling on the outer edge of your foot, about halfway to the toe where the peroneal tendon connects to the bone.

While the underside of your foot can also swell slightly, it’s much less noticeable as there’s a natural stretch under the arch.

Ankle Instability

Your affected ankle may feel unstable when you bear weight on it. You may feel like the joint is going to give way or isn’t supported by the peroneal tendons.

Worse Pain When Exercising

The pain in your ankles and feet will increase with exercise and ease with rest. You should note that exercise includes light activity like walking. Any activity that places strain on the peroneal tendons will cause the pain to worsen.



Peroneal tendonitis is most commonly an overuse injury. Activities like running on sloping ground can put strain on the peroneal tendons and cause them to become inflamed.

The repetitive nature of marathons or long-distance runs can also lead to peroneal tendonitis. Those who take part in other sports that place a lot of stress on the ankles may also be at increased risk of developing peroneal tendonitis.

If you are prone to ankle sprains you may also be more at risk of peroneal tendonitis as the ankle is already weak.

Sudden Increase in Training

If you suddenly increase your training—frequency or intensity—you may find that your peroneal tendons become overloaded. This can place excess strain on the tendons and make them more susceptible to inflammation.

High Arches

It’s also more common to develop peroneal tendonitis if you have high arches or supinate, as more pressure is placed on the outer edge of the foot when you walk or exercise.

Tight Calf Muscles

Tight calf muscles may cause the peroneal tendons to tighten as well, which may lead to inflammation and pain. Ensuring that your calf muscles are well stretched before every exercise session will reduce the chances of the tendons becoming inflamed.

Wrong Shoes

Wearing footwear that doesn’t adequately support your feet may increase your chance of developing peroneal tendonitis. Unsupportive shoes may lead to overpronation or supination, placing stress on the tendons every time you walk or run.


Not all of these treatments will work for you, but you should try each one until you find something that does work. You can also use them in combination for best results, but you should rest your feet when recovering.

Ankle Brace

An ankle brace for peroneal tendonitis can help to stabilize the joint while you’re walking, running, or jumping. This can help to prevent the tendons moving out of place or rubbing against the bone when you move.

Using an ankle brace can also be a preventative measure if you have weak ankles or are prone to ankle injuries that could lead to peroneal tendonitis.


If the pain is severe, your doctor may recommend a soft cast or walking boot to help immobilize the injured foot. It also helps you to keep the weight off of the tendons so they can heal.

If having your foot fully immobilized is not an option, then you may want to consider taping your foot for peroneal tendonitis. This will provide some support without compromising your range of motion.


Resting your foot is one of the best treatments. Take a break from any sports that place strain on the injured foot, and try to avoid walking if possible.

You can apply ice for 15 to 20 minutes at a time, 3 to 4 times a day. It’s a good idea to elevate your foot while applying ice, this will help any fluid that’s built up in the area drain, reducing swelling.

You can also use compression socks. Compression helps to increase the blood flow to the tendons, as they don’t have a great blood supply. This brings healing nutrients and helps to move fluid, leading to faster healing.


To manage the pain, you can use over-the-counter non-steroidal anti-inflammatories. Anti-inflammatories will help to reduce inflammation in the area and ease pain so you can still go about your daily activities.

Just be careful not to overdo it while you’re taking this medication, as it can be tempting to push yourself or continue as normal while your feet are feeling better.

Physical Therapy

Your doctor may recommend physical therapy for your feet. A physical therapist will give you exercises and gentle stretches to do that will help you regain flexibility, increase strength, and increase blood flow to the injured part of your foot.


If you’ve healed from peroneal tendonitis and want to prevent it from happening again, or if you have weak ankles and want to prevent it from the start, here’s what you should consider.

Change Your Shoes

Make sure your shoes support your feet properly. If you overpronate, ensure that you’re wearing shoes with some kind of stability system in them, even if you don’t do sports in them but just wear them to work.

If you supinate or have high arches, make sure you get a shoe that provides enough structure underneath the arch to prevent the foot from being unstable.

The right shoes for peroneal tendonitis will prevent your foot from rolling over and placing stress on those tendons. You may also want to consider shoes with ankle support.

Use An Orthotic

If you already have new shoes, but they don’t provide the right amount of support, you may want to choose a peroneal tendonitis orthotic instead. This means you don’t have to throw away a perfectly good pair of shoes, but instead just tailor the support to your feet.

You can get over-the-counter orthotics; however, you may need to try a few before you find one that suits you. Try to choose one that’s heat- or wear-moldable as it will contour to your feet with use.

If you want an orthotic specifically made for your feet, consider a custom orthotic made by a podiatrist.


Stretching is easy to fit into your daily routine and can significantly reduce your chance of developing peroneal tendonitis.

As one of the common causes of peroneal tendonitis is tight calf muscles, simply stretching your calves before and after exercise, and when you wake up in the morning can help to lower your chances of developing it.

Foot stretches and foot rubs can also help to keep both the calf muscles and plantar fascia loose and comfortable.

Increase Exercise Gradually

If you’re an active person who trains regularly, try to resist the temptation to increase your intensity or frequency drastically.

Try to increase by no more than 10% per week if you feel that your current training load is not enough for you.

This will prevent overuse of the tendons by allowing them time to adjust to the new workload.

Prioritize Recovery

As peroneal tendonitis is primarily an overuse injury, you must avoid overuse of the tendons if you want to prevent it.

Pace yourself and try to balance any training you do with the rest of your daily life. If you do a lot of walking during the day at work, try to balance that out with a workout that doesn’t require you moving your ankles in the same way, like rowing or cycling.

Look after your ankles and prioritize your recovery. Invest in compression socks, incorporate stretching into your daily routine, and pay attention to how your feet feel so you can get ahead of any potential problems early.

Ashraf, L., Klinger, B., Jackson, K., & Wright, A. (n.d.). Peroneus Brevis. Physiopedia. Retrieved June 22, 2022, from 

Peroneal Tendinopathy. (n.d.). Physiopedia. Retrieved June 22, 2022, from 

Peroneus (Fibularis) Longus Muscle. (n.d.). Physiopedia. Retrieved June 22, 2022, from 

Simpson, M. R., & Howard, T. M. (2009). Tendinopathies of the Foot and Ankle. American Family Physician, 80(10), 1107–1114. 

Walt, J., & Massey, P. (2020). Peroneal Tendon Syndromes. PubMed; StatPearls Publishing.