As runners, we accept that there is a certain amount of risk involved with our sport. When we are well into our Marathon Training Schedule, Hooked On Trail Running, or a first 5k, we hear about the high injury rates. And know that there is a good chance we will end up as one of the many injured runners.
We expect that maybe we will end up with Runner’s Knee or Achilles Tendonitis. But what if your pain does not seem to fit into any of the usual categories. And when you search for running injuries, the sore spot and tender area just does not seem to match anything.
Peroneal tendonitis, also referred to as peroneal tendinopathy, is a rare but aggravating injury. It can cause pain in the outside of your foot. And up the outside of your lower leg when you run.
What are the Peroneal Tendons?
Although peroneal tendinitis is not as common as the other forms of tendon pain, it does not make it any less frustrating. Especially when we cannot pinpoint the exact source of the pain.
There are actually two peroneal tendons. The peroneus longus and the peroneus brevis, which run parallel to each other. Connecting the outside of your foot to the peroneus longus and brevis muscles in your lower leg.
These tendons act in concert to evert your foot (roll it outwards) and also help assist your calf muscles in plantar-flexing your foot. They also assist in stabilizing your ankle during weight-bearing activities like running.
As with all cases of “tendonitis,” the problem is really one of degeneration and damage, not inflammation. So a more proper term would be “peroneal tendinopathy” or “peroneal tendon dysfunction.”
However, since the term tendonitis is still more common, that’s what this article will use.
How Common are Peroneal Tendonitis Injuries in Runners?
Like any tendon, both peroneal tendons, can get injured from overuse.
Unlike injuries to the Achilles or Patellar Tendon, which are fairly common and well-understood, peroneal tendon injuries are quite rare.
A study by Taunton et al., which categorized the injuries of over two thousand runners at a sports injury clinic, found only thirteen cases of peroneal tendonitis.1 This means that peroneal tendonitis makes up only about 0.6% of all running injuries. With such a small number of cases, it’s hard to draw too many conclusions, but Taunton et al. did note that nine of the thirteen cases were in men.
It’s hard to say whether peroneal tendonitis really is more common in men than women. Or if this is just random statistical noise. But injuries to the Achilles and patellar tendon are more common among men, too. So there may be something to this trend.
What Does Peroneal Tendonitis Feel like?
Peroneal tendonitis presents as a sharp or aching sensation along the length of the tendons or on the outside of your foot.
It can occur at the insertion point of the tendons. Along the outside edge of your fifth metatarsal bone. Or further up along the outside of your ankle.
Running will be painful, as will trying to dorsiflex and evert your foot, especially against resistance. There might be some stiffness and soreness if you do “ankle circles” too, or even when passively stretching the tendon.
There shouldn’t be much pain while standing or when you push gently on the injured area. However, if the outside of your foot is very tender to the touch, and if you have a lot of pain standing or even while non-weightbearing, you may instead Have A Fracture On Your Fifth Metatarsal.
These are uncommon, but can cause a lot of trouble if they aren’t addressed right away. So if you’re not sure whether you have peroneal tendonitis, see your doctor as soon as you can.
Does it matter which of the two peroneal tendons you’ve injured? From the relatively meager scientific literature on peroneal tendonitis, it does not seem like this is the case.
In fact, somewhere around 33% of all cases of peroneal tendonitis appear to involve both tendons anyways. So any rehab program will have to address both the peroneus longus and the peroneus brevis.2
Common Causes of Peroneal Tendonitis in Runners
Since peroneal tendonitis is so rare, there aren’t any large-scale studies on risk factors. The only reports extant in the medical literature analyze a relatively small number of cases.
However, one risk factor does seem to stand out.
A review of twenty-two cases of peroneal tendonitis by Clayton B. Brandes and Ronald W. Smith revealed that over eighty percent of these patients had a high-arched foot. According to the authors, feet with higher arches put more tension on the peroneal tendons, predisposing them to injury.2
This makes sense, because having a low arched foot seems to be a risk factor for posterior tibial tendon injury (the tendon on the inside of the ankle).3 We already went into detail on How Your Arch Height Affects Your Shoe Choice And The Type Of Injury You Are Most At Risk For .
Research published in 1993 also suggests that faster running speeds could put extra stress on the peroneal tendons.
Lyle Reber, Jacquelin Perry, and Marilyn Pink at the Centinela Hospital Biomechanics Laboratory in California investigated how muscular activation patterns in the muscles surrounding the ankle changed as a function of running speed in a group of healthy, injury-free distance runners.4
The researchers found that higher running speeds created a significant increase in activity in the peroneus brevis muscle. The intensity of the muscle contraction doubled when comparing an easy jog to race-pace running.
Reber, Perry, and Pink hypothesized that the rapid transfer of forces to the midfoot when running at fast speeds. And the concomitant increase in the necessity of a stable ankle, is responsible for the increased demands on the peroneus brevis.
So it follows that faster runners, and runners who do high-intensity interval workouts, are at a greater risk for peroneal tendonitis.
Might be best to stay away from the Traditional Forms Of Speed Work if a lot of what we have said so far is ringing true for you.
Some cases of peroneal tendon injury are precipitated by an ankle sprain. We have already told you How To Sprain Proof Your Ankles For Trail Running. Though given the tendons’ location on your foot, it’s easy to see how an inversion sprain could provoke tendon damage.
A 1993 report by Mark Sobel, Mark Geppert, and Russell Warren at the Hospital for Special Surgery in New York connected ankle instability from previous ankle sprains with damage to the peroneal tendons.5 This was confirmed by a 1998 article in Foot & Ankle International by researchers from the Mayo Clinic.6
If you have lingering pain after an ankle sprain, you may have injured one of your peroneal tendons as well. In some cases, even ruptured it. This can be detected on an MRI.
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Download the Peroneal Tendonitis treatment exercises and plan.
It’s a PDF with the conservative and aggressive treatment options for runners suffering from peroneal tendonitis.
How Can I Treat my Peroneal Tendonitis Pain?
When it comes to treatments, the rarity of the injury again makes things difficult. There’s no controlled clinical trials that lay out a rehab program to follow.
Nevertheless, we can make some inferences from what we know about the injury. And follow the recommendations of scientists and doctors with clinical experience.
According to Daniel S. Heckman and others at the University of North Carolina, treatment should include rest (obviously), stretching, strengthening. And proprioceptive exercises to restore proper functioning of the tendon.7
From what we know about the function of the peroneal tendons, it follows that any strengthening program should be focused on eversion of the foot against resistance, probably using an elastic band.
A similar strengthening program is proposed for Posterior Tibial Tendonitis by Alvarez et al., which we can adapt for peroneal tendonitis by focusing on eversion (roll out) of the foot instead of inversion (roll in).8
The adapted program involves doing 200 repeats of the eversion exercise every day. Starting with a very weak resistance band, and taking breaks if you need to.
Over time, you should progress towards being able to do all 200 repeats consecutively, and towards using a stronger resistance band.
For stretching, your best bet is to focus on Stretching Out Your Calf Muscles. Since tight calves could cause a more rapid transfer of stress onto your midfoot during running, which would increase demands on the peroneal tendons.
You can do straight knee and bent knee calf stretches in three sets of thirty seconds each, three times per day.
Single-Leg Balance Exercises Are The Best Way to improve proprioception and restore proper function to the peroneal tendons.
As with other single-leg balance programs for running injuries, you can start with basic single-leg balancing, then progress to adding more complex motions. Like reaching forward, to the left, and to the right with your upper body. Or working on a wobble board or foam balance mat.
These balance exercises should be done in a structured, progressive way to improve proprioception.
When you’re first starting out, work on improving your single-leg balance until you can do two and a half minutes of single-leg balancing continuously.
After that, you can start increasing the difficulty by closing your eyes, doing directional body leans, or using a wobble board.
What Other Possible Treatment Options are There?
If rest and some basic balancing, stretching, and strengthening exercises don’t fix the problem, you should consider seeing a physical therapist.
It’s possible you have some unique biomechanical problems that are contributing to your case of peroneal tendonitis. Or you may require a different set of exercises to get back on track.
If this is one of a number of injuries, your running form may be to blame.
Our running form course will analyze this for you, to make sure injuries become a rare occurrence, rather than it being rare you are healthy. One of the main reasons runners end up with injuries is because they are overstriding. Make sure you read up on our Overstriding, Cadence, And Heel Striking post for more on this.
Both Heckman et al. and Selmani, Gjata, and Gjika suggest getting custom orthotics to take stress off the peroneal tendons.7, 10
Unlike many other injuries, it does seem like there should be a difference between custom orthotics and standard over-the-counter inserts like SuperFeet or PowerStep.
Usually, the goal of an insert is to support the arch, which transfers stress to the outside of the foot.
This can be very helpful in injuries like Plantar Fasciitis or Shin Splints. But in the case of peroneal tendonitis, this could be a bad thing. Remember, over eighty percent of people who get peroneal tendonitis have high arches.
Building up arch support even more, and shifting stress to the outside of the foot (where the peroneal tendons are), could actually make the problem worse!
Custom orthotics can change this equation by keeping the arch height of the insert lower, and adding a “wedge” underneath the outside of your heel. Which can take stress off the outside of your midfoot.
If your case of peroneal tendonitis isn’t responding to rest and physical therapy exercises, a custom orthotic might be worth a shot.
If conservative treatments fail, you should see an orthopedist and get an MRI to check for a rupture in the tendon.
Especially when peroneal tendon injury coincides with an ankle sprain, there is a chance what feels like tendonitis is really a tendon rupture that needs to be repaired surgically.
Fortunately, MRI seems to be an effective method for determining the extent of damage to the peroneal tendon.7 If you have a tendon rupture, or if there is very severe tendon damage, you may need surgery to fix it.
Outline of Treatment
Conservative treatments
These are methods that are fairly simple, inexpensive, and can be done on your own at home.
- Calf stretching
- Eversion exercise with a resistance band
- Balance exercise
Aggressive treatments
These are treatments with more cost and less certainty about outcomes, but may prove useful in recalcitrant cases.
- See a podiatrist or an orthopedist and ask about getting a custom orthotic. In the case of peroneal tendonitis, standard over-the-counter orthotics are probably not going to be very helpful because of the biomechanics of the injury.
- Consider dry needling. Some runners find it works very well with peroneal tendon issues. If you are desperate, it might be worth a try.
- See a physical therapist who is familiar with running injuries to ensure that you don’t have any weakness, tightness, or gait abnormalities that are causing your tendon problems.
- If conservative treatments still aren’t working after several weeks or months, see a trusted orthopedist so you can get an MRI to check for a tendon rupture or severe tendon damage and discuss the possibility of surgery.
When Can I Return to Running?
Avoiding running on the tendon while it’s injured seems to be the right idea.
A 1994 case study describes a 49-year-old runner who suffered an acute rupture of the peroneus longus tendon in the middle of a ten-mile road race after running on chronic tendon pain for several months. This runner did recover and return to training. But only after surgery and a year of rehab! 11
As with any injury, you should be gradual and patient in your return to running.
Research on Achilles and patellar tendonitis suggests that mild pain when returning to running is not a cause for major concern as long as the pain does not get progressively worse.12
This “pain monitoring” approach (which Brad Beer talked about in a recent podcast interview) has not been tested in injuries to the smaller tendons of the feet. However, if you’re in doubt, be cautious and wait for your tendon to heal before returning to full training.
The good news is that the peroneal tendons are not known to be particularly resistant to healing like the Posterior Tibial Tendon or the plantar fascia. So with some patience and the right rehab program, you should be back to training soon.
And please do us a little favor and share this guide with others, for there’s a good chance that it could be the guide they are looking for with this frustrating injury!
8 Responses
My eyes didn’t want to believe when I saw this article, you describe point-by-point everything that I needed to know about this injury and a way to fix it that totally makes sense.
After almost 2 years in useless visits to doctors and physical therapists, this is a glace of fresh air and hope. I started yesterday the exercises and they feel so good, it really makes sense. Thank you so much.
There is another cause of peroneal tendinitis. While it seems pretty rare it’s something I’m dealing with right now. Some people have accessory navicular (an extra bone in their foot). Usually this “extra bone” is on the inside of the foot, but in my case it’s on the outside by the fifth metatarsal. It’s been there my entire life, but it hasn’t started causing issues with my peroneal tendon until recently.
The treatments you’ve documented are pretty much the same as what my doctor prescribed with one addition. Since I actually have a fairly low arch she recommended wearing a foot/ankle brace that helps to turn the foot outwards. That takes some pressure off the tendon.
I believe I have the exact problem you have. An extra bone in the upper part of my foot and a fairly arch. My pain started three months ago with first a painful calf strain, then to an achilles heel tear and now Peroneal Tendonitis pain on the inside and outside of my ankle. Went to a sports doctor who didn’t help. Who should I see. Can you recommend a special wrap or brace to help?
Anyone dealing with this injury? Post a comment and we’ll do our best to help you out.
i have been diagnosed with plantar fasciitis and peroneal tendonitis! I have had orthotics (cast) made, have had injections, MRI!! My podiatrist wants to build up my arch every time i go in or do more injections in my arch!! my arches, heels and outside of my foot on the 5th metatarsal and the pain runs up my calf, hurts every time I walk, weather standing or moving! I have tried taping my ankle with no relief! I wear brooks with my orthotics, i am having a hard time making it through my 12 hour shift at work the pain is unbareable!!
I am working through the issue right now. I have been using a trigger point foam roller on IT band and lower calf along along with a Rogue supernova ball for isolated treatment directly above and behind the ankle. Been at it for a week and noticing significant progress. This treatment approach also worked when I had intense knee pain that was a result of a tight IT band. I find most tendon issues can be addressed with mobility exercises on a roller as with some type of ball and the that pain is caused by an area without pain, so you have to go hunting for it.
I think I have a Peroneal injury in BOTH feet at the same time??? Is it even possible?
Last Saturday, I went for a run that was longer than my usual. I usually do 7-12K, and this time I did 16K. (Not bright…I know) . Felt fine that day and night. The next day mid morning, I was at the market and suddenly it felt like knives were being stuck in the sides of my feet with each step. I hobbled my way home, and have been using Ice and Ibuprofen every since. As of today (Wednesday) I feel a little better, but still not great. It hurts way more when I wear shoes. It hurts less if I walk on my toes and avoid my heel striking the ground.
I see other posts about this, but have not seen a case where both feet are affected. I talked to friends who train pretty hard and they have never heard of this happening in both feet. Could it be from my shoes since it is in both feet?
If anyone has any insight into this, I would really appreciate it. I am really bummed because I felt great after the run and was looking forward to doing longer runs, and now it feels like I will not be running for quite some time.
Thanks!
Arrived at this helpful page as I am into this mysterious injury week 5 now but to be clear there are three main factors that have given my Peroneal tendonitis condition:
1/ Arched foot
2/ Speed and interval training more than once a week
3/ Some of the interval course (a road) has a slight slant for a small bit. Not advisable a coach told me later
So being impatient and stubborn I thought after 3 days rest and icing I’d be fine and did jogging and speed walking for the first week after despite some pain. Major fail. I’ve had to start all over again from scratch and do the 2-3 weeks with no running and little walking. This injury plays with your head and you think ok let’s get back to running. Avoid this temptation!
Happy running all
My advice to anyone who even thinks they have this injury is to do absolutely no running for about a month. Do the exercises as outlined above. Even then you may think you are ready to hit the road with some 75-90% interval efforts. I’d stay clear of that for another month.