Over the years, I’ve had hundreds of patients who think they have plantar fasciitis. Fortunately, for a lot of them, they didn’t actually have this painful foot disorder. Unfortunately, plantar fasciitis has become a bucket term for any pain on the bottom of the foot. Here are some conditions that can masquerade as plantar fasciitis.
What is Plantar Fasciitis?
The plantar fascia is a broad band of fascia that runs from your toes to your heel. It acts like a bow string, giving inherent stability to your foot. When that tissue is put under stress, for various reasons, the collagen fibers can become inflamed and even tear, giving you pain on the bottom of your foot. Typically, this happens where the plantar fascia attaches to your heel. So, if you have sharp pain that’s centrally located in front of your heel bone which feels worse in the morning or while going up and down stairs or any time you’re up on your toes, you might have plantar fasciitis.
However, there are other structures that are close in proximity to the attachment of the plantar fascia that can also cause issues and be confused for plantar fasciitis.
Nerve Entrapment
The medial calcaneal branches of the tibial nerve exit through the plantar fascia right in front of the heel bone. Sometimes, that nerve can get bound up and not move freely through the plantar fascia, causing extreme pain. While in the same area where we would see plantar fasciitis, it is a very different kind of pain and treatment. This is one of the things we would differentially diagnose in a PT evaluation and say, “Not plantar fasciitis.”
Calcaneal Fat Pad Inflammation
Between your skin and the calcaneus, there is a layer of fat that provides cushion for your heel. With repetitive loading of the heel, wearing shoes that are played out or low cushion or just walking around barefoot on hard surfaces, we can irritate this fat pad. That inflammation manifests as pain directly in the center of your heel bone. Again, close to the plantar fascia but further back, directly on the bone. I have also seen a similar injury in people who have been put in an immobilization boot for foot and ankle injuries for an extended period. When immobilized and potentially non-weight bearing for weeks, the fat pad can atrophy, putting more stress on the calcaneus. Once they are out of the boot and immediately return to running, the heel bone is at risk of bruising. Again, not plantar fasciitis.
Tibialis Posterior or Flexor Hallucis Longus Tendonitis
Tibialis posterior and flexor hallucis longus are muscles that sit deep behind the shin bone (tibia). Those muscles come down with their tendons crossing behind the ankle bone and wrapping underneath the foot. Their major role is to stabilize the ankle, as well as form the arch of the foot. The flexor hallucis also curls the big toe. When someone is flat-footed, has poor foot strength, runs on very uneven surfaces or uses shoes that don’t have good heel support, amongst other things, these tendons can get inflamed. Typically, people will report pain in their arch, or on the side of their heel bone, just up from the bottom of their foot. Again, these structures are close to the plantar fascia, but definitely not plantar fasciitis.
So, what can you do help keep these injuries at bay?
Ways to keep your feet healthy include:
- Create a well-rounded strength routine. When our core and hips are weak, the whole kinematic chain breaks down, putting more stress on your feet. Get in the gym. Simple foot exercises like picking up marbles with your toes can help too.
- Implement regular tissue work. Use that foam roller and don’t be afraid to use a golf ball on the underside of your feet to maintain tissue mobility.
- Make good shoe choices. Change out your shoes once they are played out, and don’t be afraid to try shoes with different drops. Just remember, the lower the drop, the more stress on the plantar fascia.
- Use good running form. In previous articles, I’ve touched on the importance of allowing your ankle to relax when your foot is in the air. This offloads a lot of structures, including the plantar fascia, decreasing the risk of tissue overuse injuries.
There you have it. Sometimes, the pain you’re feeling on the bottom of your foot is plantar fasciitis and sometimes it’s not. Hopefully this has helped you understand the different structures that are at play when talking about foot pain. If you are having foot pain, please go see your PT. Foot problems can turn into big issues quickly, and it is best to nip things in the bud as soon as possible. See you on the trails!
Medical disclaimer. What I write here in no way substitutes for an in-person, thorough evaluation by a licensed physical therapist. As with many body issues, there can be multiple factors involved with your aches and pains, and, in some cases, more serious underlying conditions that can be manifesting as physical symptoms. It is always best to have a PT that you can see when you have concerns, so that you can make sure your personal situation is being addressed appropriately and safely. This column should, in no way, serve as a substitute for seeing a licensed medical practitioner.