When it's NOT Shin Splints: Peroneal Tendonitis

Updated: Aug 22

"Why does this part above my ankle hurt? It's so hard to describe! It's almost into my foot, but not quite…

I've tried a couple rest days. I finally took an entire week off.

I'm really hoping I can run pain free today...but…I'm scared. What if it's still there? What if I have to take even more time off? I've been doing these exercises off the internet every day; why don't I feel any improvement?"

Is this your story, runner?

The frustration.

Confusion.

Disbelief.

That sneaky dread in the pit of your stomach thinking, "it might not work; it could! But what if.."

I see you, runner.

I hear you.

And I've treated exactly this in the clinic.

So who's the culprit of the mysterious side ankle pain that may feel like shin splints but not quite?


What's causing your symptoms that seem to move around, traveling up maybe to your knee, then back down to the ankle, then into the foot?

You're not crazy.

It's just peroneal tendonitis. (I know, what a mouthful).



Meet Your Peroneals

These are the twins to blame: peroneus longus and peroneus brevis.



Are the pieces starting to fall into place?


In that first image, did you notice how the tendons of these long muscle actually plug into the bottom of your foot? (sneaky, right?)

And then in the second image showing "area of pain", do you sometimes get symptoms there? But then you also get symptoms up a little higher?


I've seen both, and it was the symptoms higher up near the knee that got me scratching my head (yup, even physical therapists get stumped sometimes haha).

But what makes peroneal tendonitis so tricky?

  • It sometimes happens at the same time as shin splints or medial tibial stress syndrome (MTSS), but typically MTSS pain is located on the inside of your ankle and on the front of the shin. (hence the confusion. Want to learn more about shin splints? Click HERE!)