Conditions Often Mistaken for Plantar Fasciitis

A number of conditions can cause severe foot pain

Female foot heel pain with red spot.
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Plantar fasciitis is a painful condition affecting feet that you can feel with every step you take. The main symptom of plantar fasciitis is pain in the arch of your foot. It's usually localized at the sole of your foot, but the pain can be perceived as radiating throughout parts of your foot, ankle, and lower leg. That means plantar fasciitis might be confused with other conditions affecting your foot.

A number of conditions can cause foot pain and be mistaken for plantar fasciitis. These conditions typically must be evaluated and ruled out before a diagnosis of plantar fasciitis.

Ruptured Plantar Fascia

In plantar fasciitis, the plantar fascia has micro-tears throughout the tissue. With a ruptured plantar fascia, the tears are larger and represent a significant injury. The two conditions have similar symptoms, but they are 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 significant trauma. If you suffer from plantar fasciitis, it could worsen, weakening the plantar fascia to the point that it ruptures. If your foot is otherwise healthy, then it usually occurs during trauma or significant impact to your foot.

Rupturing your plantar fascia is usually accompanied by a “pop” resulting in severe pain and an inability to bear weight on that foot. Swelling and bruising often soon follow. Surgery and other medical procedures might be needed to help the plantar fascia mend.

Arthritis

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

Not only can the location of pain from arthritis be confused with plantar fasciitis pain, but also the occurrence of pain can be similar. Arthritis pain usually is worse when the arthritic joint is being used. When the joint is at rest there might be no pain, the same pattern you see in plantar fasciitis. So you might have arthritis in your heel and not notice it until you take a step.

Arthritis can be more painful when the body part is cold. The first step in the morning might be the most painful of the day with both plantar fasciitis and arthritis of the foot, simply because the anatomy is cold and tight and has not warmed up. The pain may dissipate with either as the foot warms up and blood flows more robustly.

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

Stress Fracture

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

Some stress fractures are a single crack in the bone, while others might be an interweaving of small cracks, like the cracked shell of a hard-boiled egg.

If the stress fracture is in your heel, toe, or metatarsal, then the pain might seem to be coming from the same spot as plantar fasciitis and feel like an injured plantar fascia: The more pressure you put on it, the more pain you feel.

A stress fracture usually is distinguished from plantar fasciitis by pinpointing the location of the pain. Pain from a stress fracture also doesn't tend to dissipate the same way that pain from plantar fasciitis does as the fascia gets warmed and loosened up. 

If the pain comes from the top of the foot, it is more likely to be a stress fracture in the metatarsal, which is prone to developing such fractures. 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 to be coming from the same place as does plantar fasciitis.

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

Circulatory Issues

Issues with your circulatory system, such as bad circulation or cardiovascular problems, can cause symptoms similar to plantar fasciitis. Your feet are the body parts farthest from your heart and 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're walking on a cold floor?

Gravity and weight are also factors. Your blood pressure is higher in your lower body, especially in your feet, than it is in your upper body because there's more pressure on it. Inflammation in your feet and lower legs—from being on your feet for a while, for example—can further constrict blood vessels.

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

All this can lead to pain, which can be caused by weaknesses in the blood vessels resulting in a backup of blood flowing, creating painful pressure. 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 your foot falling asleep, you might feel a deep, throbbing ache. Pain also can be caused by blood clots, which can lead to life-threatening situations.

Because circulatory issues are serious, they should be thoroughly vetted and ruled out if you're having pain in your foot, even if you think it's probably plantar fasciitis. This is especially true if you have varicose veins, tingling or swelling in the foot, or the same symptoms in both feet because plantar fasciitis is typically a single-foot injury.

Your doctor can evaluate your cardiovascular health by monitoring your blood pressure and blood oxygen level. The doctor might also suggest an EKG and a cardiovascular stress test to find out what's going on.

Nerve Entrapment

Nerves can cause extreme pain when compromised. The pain might not be felt where the nerve is compromised but at the end of the nerve structure, where the nerve's chemical signals are parsed out to the cells that receive them.

Nerve entrapment syndrome sometimes is confused with plantar fasciitis. In nerve entrapment syndrome, pressure is placed on a nerve by some other body part, such as a bone, muscle, or cyst. When a nerve is trapped or "pinched" by other tissue, that tissue squeezes it and the nerve sends out a pain signal. This can happen to many 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 there because it's a mass of nerves, ligaments, and muscles squeezing through a skeletal structure called the tarsal tunnel, similar to the wrist's carpal tunnel.

If the tibial nerve is pinched, then you feel pain in the bottom of your foot much like with plantar fasciitis. Unlike plantar fasciitis, you might also feel tingling or numbness in the bottom of your foot. You should 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 can be mistaken for plantar fasciitis. Sciatica comes from farther away than tarsal tunnel syndrome, however. Sciatica is a pinching or irritation of the nerve in your spine.

Your spine is composed of a number of bones, or vertebrae. Between each vertebra is a disc, similar to a gel pad, that cushions the vertebrae against each other and allows for flexibility of the spine. A disc might get irritated and, like most irritated body parts, become inflamed.

The inflammation usually results in swelling in one small part of the disc, which makes the disc act like an old rubber inner tube. If there is a weak spot in the wall of an inner tube, it will bulge when you inflate it. The disc bulges, and if it takes more damage, it can rupture. This is a herniated disc.

The main nerve column in the body runs along the spine. The sciatic nerve, one of the body’s largest nerves, runs in this nerve bundle. When the disc bulges or ruptures, it can put pressure on part of the sciatic nerve, resulting in sciatica. This often sends a shooting pain down your leg, but the pain might be felt in your foot.

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

Fat Pad Atrophy

Atrophy of the heel's fat pad also might be confused with plantar fasciitis. As you age, this fat pad becomes thinner. Other factors might affect the thinning, but science doesn't fully understand what's happening.

This fat pad is the first cushion for your gait. The pad can become so thin that it doesn't cushion the heel bone, and the heel suffers from repetitive trauma that can result in painful irritation, inflammation, a bone bruise, or a stress fracture.

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

Achilles Tendon Rupture

Like a ruptured plantar fascia, an Achilles tendon rupture may create symptoms similar to plantar fasciitis. A ruptured Achilles tendon is 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 have difficulty bearing weight on the foot. The pain can be severe and doesn't necessarily dissipate when you are off your feet. Another difference between a ruptured Achilles tendon and plantar fasciitis is that the pain with a ruptured Achilles usually is felt along the back of the heel; with plantar fasciitis, pain is more likely to be felt along the front of your foot.

Tendonitis

Tendonitis is similar in nature to plantar fasciitis, as 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 several tendons in your foot.

Tendonitis in any foot tendon can result in pain when you step and stretch the tendon. The pain also should dissipate as the tendon warms and loosens 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 results in pain along the back of the heel, while plantar fasciitis generally means pain in front of the heel. 

Bursitis

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

Bursitis can be differentiated from plantar fasciitis by direct pressure. Since an inflamed bursa is tender and plantar fascia has little sensitivity, massaging it without much pain would indicate plantar fasciitis. If massaging or just touching it causes a lot of pain, then it is more likely to be bursitis.