Conditions Often Mistaken for Plantar Fasciitis

X-ray of heel with Plantar Fasciitis or Jogger's heel, 48 year old male
(Cultura Science/PhotoStock-Israel/Getty Images)

Plantar fasciitis is a painful condition affecting your foot and can be felt with every step that you take.  The main symptom of plantar fasciitis is a pain in your foot. It is usually localized at the bottom of your foot (the sole) but the pain may be perceived as radiating throughout parts of your foot, ankle, and lower leg. Because of this plantar fasciitis may be confused or mistaken with other conditions affecting your foot, or vice versa.

There are a number of conditions that cause foot pain and can be mistaken for plantar fasciitis. These conditions typically need to be evaluated and ruled out when making a diagnosis of plantar fasciitis.

Conditions most often mistaken for plantar fasciitis include:

Ruptured Plantar Fascia

In plantar fasciitis, the plantar fascia has micro-tears throughout the tissue. With a ruptured plantar fascia, those tears are now big and a significant injury has occurred. The two conditions have similar symptoms but they are often differentiated by the severity of pain and cause of the injury.

A ruptured plantar fascia is almost always significantly more painful than plantar fasciitis. It also usually has a precursor: either plantar fasciitis or a significant trauma. If you suffer from plantar fasciitis, you do run the risk of it worsening and weakening to the point of your plantar fascia rupturing. If your foot is otherwise healthy, then it usually occurs during a trauma or significant impact to your foot.

The rupturing of your plantar fascia is usually accompanied by a “pop.” The result of that pop, the rupturing of the plantar fascia, is severe pain and an inability to bear weight on that foot. Swelling and bruising often soon follow the rupturing.  

Surgery and other medical procedures may be needed to help the mending of the plantar fascia.

Arthritis

Arthritis is a common problem that many people suffer from somewhere in their body. When arthritis occurs in the lower leg, ankle, or some part of the foot, it can exude a pain that may be perceived in the same way that pain from plantar fasciitis is perceived.

Not only may the localization of pain be confused with plantar fasciitis pain but the occurrence of the pain can be similar. Arthritis pain is usually worse when the joint suffering from arthritis is being used. When the joint is at rest, then the pain may not even occur, which is the same pattern you see in plantar fasciitis. So you may have arthritis in your heel and only notice it when you take a step and engage the heel.

In another similarity to plantar fasciitis, arthritis can often be more painful when the body part is cold. The first step in the morning may be the most painful one you take all day with both plantar fasciitis and arthritis in the foot, simply because the anatomy is cold and tight and has not significantly warmed up.  The pain may dissipate with both as the foot warms up and blood begins flowing more robustly.

To diagnose plantar fasciitis, arthritis must usually be ruled out first. Arthritis can be diagnosed with a more thorough workup by your doctor.

Imaging tests may be needed as well.

Stress Fracture

One of the conditions most commonly mistaken for plantar fasciitis is a stress fracture. A stress fracture is normally a partially broken bone. Instead of the bone being broken all the way through, the bone is only cracked along a surface. Stress fractures are usually shallow along the surface of the bone but they may be deep.

Some stress fractures are a simple, single crack along the bone while others may be a crazing, interweaving of small cracks (like when you crack an egg shell on a hard boiled egg).

If the stress fracture is located in your heels, toes, or metatarsals, then the pain may seem like it is coming from the same spot as pain from plantar fasciitis. A stress fracture exhibits pain in much the same way as an injured plantar fascia does.

The more pressure you put on it, the more pain you feel.

With that kind of similarity in symptoms, the two conditions can easily be taken for one another. A stress fracture usually is differentiated from plantar fasciitis by pinpointing the location of the pain. Pain from a stress fracture also does not tend to dissipate in the same way that pain from plantar fasciitis dissipates when the plantar fascia gets warmed and loosened up.  

If the pain is coming from the top of the foot, it is more likely to be a stress fracture in the metatarsal, which is prone to developing stress fractures anyway. If the pain is in the bottom of the foot, it is more likely to be plantar fasciitis. Pain from a stress fracture in the heel bone often seems like it is coming from the same place as does plantar fasciitis.

An x-ray can typically identify a stress fracture definitively and is often used to confidently rule out a stress fracture as a cause of your pain, even if the probability of it being plantar fasciitis is much higher.

Circulatory Issues

Issues with your circulatory system, that is, bad circulation or cardiovascular problems, can cause symptoms similar to plantar fasciitis. Your feet are the body parts farthest away from your heart. As such, these extremities tend to feel the effects of poor circulation first. Are your feet ever cold while the rest of you is warm, and not because you are walking on a cold floor?

Coupled with your feet being far away from the central blood pump, the heart, are the effects of gravity and your weight. Your blood pressure will be higher in your lower body, especially in your feet, than it is in your upper body. That’s because there is actually more pressure on it. Also any inflammation you have in your feet and lower legs from being on your feet for a while can further constrict blood vessels.

Not only does blood flow down to your feet but it has to be pumped back up. The weakening of those support systems, the one-way valves in your veins, results in varicose veins.

All of this can lead to pain. The pain can be caused by weaknesses in the blood vessels that cause a backup of blood flowing. That creates extra pressure which can hurt a lot. Pain may also be caused by a lack of oxygen and nutrients getting to the tissue in your feet because of poor blood flow. Instead of having your foot fall asleep, you might get a deep throbbing ache. Your pain may also be caused by blood clots which can lead to serious and life-threatening situations.

Because of the seriousness of circulatory issues, they should be thoroughly vetted and ruled out if you are having pain in your foot, even if you think it is probably plantar fasciitis. This is especially true if you have varicose veins, tingling in the foot, swelling in the foot, or experience the same symptoms in both feet (since plantar fasciitis is an injury to a single foot).

Your doctor can evaluate your cardiovascular health by, above other things, monitoring your blood pressure and blood oxygen level. They may also want to perform an EKG and a cardiovascular stress test to find out what is going on inside your body.

Nerve Entrapment

Nerves are funny things, just ask the funny bone (which is actually a bundle of nerves). They can cause an extreme amount of pain when compromised. And the funny part is that that pain may not be felt where the nerve is being compromised at but, instead, it may be felt at the end of the nerve structure where the nerves chemical signals are parsed out to the cells that receive them.

Sometimes confused with plantar fasciitis is nerve entrapment syndrome. In nerve entrapment syndrome, pressure is placed on a nerve by some other body part (like a bone, or muscle, or a cyst).  When that nerve is trapped, or you have a "pinched nerve," by the other tissue and that tissue squeezes it, then the nerve sends out a pain signal. This can happen to a lot of nerves in your body, but the one most commonly mistaken for plantar fasciitis is the tibial nerve, which runs down the back of your leg.

When the tibial nerve is pinched or entrapped near the ankle, it is called tarsal tunnel syndrome. The tibial nerve is most often entrapped at this location because it is a mass of nerves, ligaments, and muscles passing through a skeletal structure (the tarsal tunnel). This is similar to the carpal tunnel of the wrist.

If the tibial nerve gets pinched, then you feel pain in the bottom of your foot much like with plantar fasciitis. Unlike plantar fasciitis, you may also feel tingling or numbness in the bottom of your foot. You should also be able to replicate the symptoms without placing weight on your foot. If you can perform the same motions and pinch the nerve with your foot elevated, then the pain is most likely not coming from the plantar fascia.

Sciatica

Sciatica is another nerve-induced pain that may be mistaken for plantar fasciitis. Sciatica comes from much farther away than tarsal tunnel syndrome, however. Sciatica is a pinching or irritation of the nerve that occurs in your spine.

Your spine is composed of a number of vertebrae. Vertebrae are the bones of your spine. Between each vertebra is a disc. This disc is like a gel pad that cushions the vertebrae against each other and allows for the extreme flexibility of the spine. From time to time, a disc may become irritated. Like most body parts, when it gets irritated it, becomes inflamed.  

The inflammation usually results in a swelling in one small part of the disc. In this case, the disc acts like an old rubber inner tube. If there is a weak spot in the wall of the inner tube somewhere, it will bulge out when you inflate it. The disc bulges out like that and if it takes more damage, it can actually rupture.  This is called a herniated disc.

The main nerve column in the body runs along the spine. The sciatic nerve is one of the body’s largest nerves and runs in this nerve bundle. When the disc bulges or ruptures, it can put pressure on part of the sciatic nerve, called sciatica. This often sends a shooting pain down your leg. However, the pain may be felt in your foot and not in your leg.

As with other nerve pain, you may also feel a tingling or numbness which can differentiate sciatica from plantar fasciitis.

Fat Pad Atrophy

Atrophy of the fat pad of the heel is another syndrome that may be confused with plantar fasciitis. As you age, the fat pad on your heel becomes thinner. This thinning process is different for everyone. There may also be other factors that affect the thinning but science has yet to fully understand what is happening.

The fat pad at your heel is the first cushion you have for your gait. In some people, the pad becomes so thin that there is not enough cushion for the heel bone and the heel begins to suffer from repetitive trauma. This trauma can result in irritation, inflammation, a bone bruise, a stress fracture, or it can just be downright painful. 

The pain often occurs in the same location as pain from plantar fasciitis. The pain may also be worse in the morning and dissipate as you loosen up. A doctor can usually determine if this is a cause of pain by examining the thickness of the heel’s fat pad.

Achilles Tendon Rupture

Much like a ruptured plantar fascia, a rupture in your Achilles tendon may present with similar symptoms like plantar fasciitis. In a ruptured Achilles tendon, you have a major tear in the thick tendon that runs along the back of your ankle from your calf to your heel.

With a ruptured Achilles tendon, you will have difficulty bearing weight on the foot. The pain can be severe and does not necessarily dissipate even when you are off your feet. Another difference between a ruptured Achilles tendon and plantar fasciitis is that the pain with a ruptured Achilles tendon is usually felt along the back of the heel and with plantar fasciitis, it is more likely to be felt along the front of your foot.

Tendonitis

Tendonitis is a type of injury that is very similar in nature to plantar fasciitis. After all, the tissue that makes up the plantar fascia is the same type of tissue that makes up a tendon. Tendonitis can occur in any tendon within your body and there are a number of tendons in your foot.

Tendonitis in any one of the foot tendons can present with pain when your step and stretch the tendon out. The pain should also dissipate as the tendon warms up and gets loosened up.

The tendon in the foot most likely to develop tendonitis is the Achilles tendon along the back of your foot. You can usually distinguish between Achilles tendonitis and plantar fasciitis by the location of the pain.  Achilles tendonitis generally presents with pain along the back of the heel, while plantar fasciitis generally presents with pain in front of the heel. 

Bursitis

Bursitis is another repetitive stress injury that can occur throughout the body. Bursae in the foot can be stricken with inflammation and develop bursitis just like their more commonly stricken brethren in the knee, elbow, shoulder, and wrist. An inflamed bursa is tender and exudes pain when it is compressed. If this occurs in the foot, especially in a bursa at the bottom of the foot, it can present with symptoms similar to plantar fasciitis.

Bursitis may be differentiated from plantar fasciitis by direct pressure. Since an inflamed bursa is tender and a plantar fascia has very little sensitivity, the application of direct pressure to the injury should tell you a lot. If you can massage it without much pain, then it is leaning towards plantar fasciitis. However, if massaging or even just touching it causes a lot of pain, then it is more likely to be bursitis (or a stress fracture, or infection, if those have not been ruled out yet).