While on vacation in Mexico, Nikola went for a longer than normal barefoot walk on the beach. She noticed some pain in her heel the next morning after getting out of bed. After suffering through the rest of her vacation, she made an appointment with her podiatrist. She was given a diagnosis of plantar fasciitis and a boot to wear for 6 weeks. Her heel pain worsened after a week out of the boot, and she came to see her trusty physical therapist at ALTA for help.
What ALTA told her:
Plantar Fasciitis is the Most Overdiagnosed Foot Disorder.
First, the name plantar fasciitis is misleading.
“Itis” refers to an inflammatory condition. Pain coming from the plantar fascia is not inflammatory in nature, similar to how tendon“itis” doesn’t exist. Yes, some inflammatory markers may be present but at a fraction of the amount seen in a true inflammatory condition.
“But taking anti-inflammatories improved the pain for my plantar fasciitis.”
Those anti-inflammatories may be decreasing inflammation in other structures near the plantar fascia. But they also knock down an excessive healing response, which is the true cause of plantar fascia pain.
Plantar fasciopathy is a better technical name (a problem in the plantar fascia), but we can just call it what it is – plantar fascia pain. Plantar fascia pain is usually a problem in load tolerance. Wearing a boot will unload the plantar fascia – creating increased sensitivity in the tissue. This condition should instead be treated by loading the plantar fascia.
Second, there are MANY other structures near the plantar fascia.
Two tendons (flexor hallucis longus and flexor digitorum longus) that curl the toes cross over each other near the middle of the plantar fascia. (It even has the cool name of “The Master Knot of Henry”). The tendon sheaths that surround those tendons may rub against each other causing irritation in the tendon sheaths themselves. There is also a nerve (the medial plantar nerve) that crosses under these two tendons, and that nerve could be the source of pain.
There is a fat pad under the heel. Too much pounding may irritate it or bruise it. A heel cup can help add some cushion.
The most common actual diagnosis of heel pain that we is entrapment of a nerve.
The nerve, the First Branch of Lateral Plantar Nerve, AKA Baxter’s Nerve, crosses underneath the plantar fascia’s attachment to the heel bone. If you are poking on the plantar fascia, you are poking on Baxter’s Nerve. Its only job is to tell the muscle that moves your little toe out to the side (abductor digiti minimi) to contract.
So, if your doctor has poked on the plantar fascia, noted its tenderness, and diagnosed you with “plantar fasciitis” without testing your nerve sensitivity or testing your strength in various positions, you may have been misdiagnosed.
Here’s a way to test for yourself if your pain may be coming from a nerve:
Palpate Baxter’s Nerve:
Now Palpate Baxter’s Nerve Under Tension:
If that tenderness changes, it is likely a nerve problem. Only a nerve continues all the way up to the hip from your foot, and if you can influence that sensation with a hip movement, you are influencing those structures that cross that joint only.
This isn’t as easy to do yourself, and we at ALTA, may need to help with the assessment part.
How else can you differentiate between these potential causes of heel pain?
Location of tenderness:
Fat pads will often be tender off to the sides of the plantar fascia. This is most commonly associated with high, rigid arches because a rigid arch won’t disperse the load when landing on that foot.
Baxter’s Nerve will be tender where it branches off the lateral plantar nerve just in front of the heel bone. There will also be a change in tenderness with a straight leg raise that increases tension on the nerve. (see pictures above)
Functional Strength Testing:
Fat pads shouldn’t interfere with any strength – they only talk to you when you put your heel down.
Plantar fascia pain will likely show signs of weakness in the calf when doing a heel raise.
Entrapment of Baxter’s Nerve may show up as weakness of your Abductor Digiti Minimi
(That’s the muscle that pushes your little toe out to the side)
If you can’t do this, and mutter to yourself, “Are we actually supposed to be able to do this?” The answer is yes. Yes you should be able to do that. Start learning how to do it right now:
Tension Tolerance:
If you have pain with a heel raise – does that pain also increase when the big toe is pushed up further?
Does that pain then decrease with prolonged holds and with repetitions ?
If you answered yes to both – that is probably plantar fascia pain. And you just found the most important exercise for you to do (pictures down below).
If the pain worsens – we are leaning more towards a nerve injury – this position may be stretching and squishing your nerve and nerves don’t like to be squished for long periods.
Exercises to Try:
For Baxter’s Nerve Entrapment:
For Plantar Fascia Pain:
Depending on the severity of true plantar fascia pain, we have have to start you off on a much smaller range…
And We Haven’t Even Touched on the Spine’s Contribution to Foot Pain…
This really is a whole nother topic for another day.
But a quick screen could be: If you stand up and have pain – does that pain change when you bend forward or backward? If yes – there is probably a spine component. And you should probably work on exercises that move your spine into the pain relieving position.
Stay tuned for an upcoming blog post on this.