Unlocking the Hidden Health Clues in Your Feet

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From the condition of your skin and hair to scabs and even tears, the external appearance of your body can provide hints about your health.

Feet are often overlooked when it comes to understanding the anatomy of the body. Did you know that they are connected to nerve fiber tracts from the brain? This connection allows you to stand, balance, and even wiggle your toes. Additionally, blood vessels in the feet are linked all the way back to the heart.

Our feet can reveal a lot about our health, including viral infections, cardiovascular diseases, and neurological disorders. Let's look at a few examples.

Hand, foot and mouth disease

Infectious diseases tend to affect different parts of the body.

Measles typically starts with small spots on the face or in the mouth that resemble grains of sugar. The exact reason why it targets these areas is not fully understood. Pityriasis versicolor, a fungal infection, usually appears and remains on the torso.

Hand, foot and mouth disease (HFM) begins in the hands, feet, and mouth. It is caused by the coxsackie virus and results in raised pink-red spots that may blister. Contrary to its name, the rash can also spread to the legs and buttocks. If a new rash appears on the feet, it could be a sign of HFM and should be checked by a doctor.

HFM is a common childhood illness that is highly contagious. Fortunately, it typically goes away on its own after a few days without needing any treatment.

It is important not to mix up HFM with foot and mouth, or better known as hoof and mouth. Foot and mouth is caused by a different virus that mainly affects cloven-hoofed animals like cows and sheep. In 2001, the UK experienced an epidemic due to this disease.

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Heart, vessels and feet

Our circulatory system is responsible for delivering blood to every part of our body, from head to toe. As the blood vessels travel to the extremities, they divide and become smaller, like branches on a tree.

We have all felt the discomfort of having cold feet, especially when walking barefoot at home or on chilly days. While it is normal for feet to feel cool to the touch, they should not turn blue or become painfully cold.

Severe symptoms like discoloration and pain could be signs of a condition known as blue toe syndrome. This condition is often caused by tiny masses called microemboli, which are made up of cholesterol deposits. These microemboli can move through larger blood vessels easily, but they may have difficulty passing through smaller vessels.

When these microemboli reach the smaller vessels in the feet, they can get stuck, leading to a blockage in the blood supply. This lack of oxygen can cause the tissues in the feet to change color and become painful.

Blue toe syndrome can have serious consequences, such as tissue death, breakdown, and the development of gangrene. In severe cases, amputation of toes or even the entire foot may be necessary.

Some people refer to this rare condition as "trash foot" due to the noticeable discoloration that occurs in the feet.

The main cause of tiny cholesterol fragments is most likely aneurysms and atherosclerosis. These are conditions where blood vessels have either expanded or become hardened near the feet. When trash foot occurs, it is usually after surgery for these conditions, like aortic aneurysm repair. The procedures can disrupt the vessels, leading to emboli breaking off.

In addition to trash foot, there are other signs in the feet that may indicate cardiovascular disease. Raised red swellings on the feet (and hands) could be a sign of a heart infection called bacterial endocarditis. These swellings can be painless, known as Janeway lesions, or sore, referred to as Osler's nodes.

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The Babinski sign

Issues with the nervous system can be indicated by the toes.

If you've seen medical shows like "ER" or "Grey's Anatomy," you may have heard about the Babinski reflex when a character mentions "upgoing plantars" during a patient exam. When a doctor identifies the upgoing plantar, they may show concern by furrowing their brow - and it's for a good reason.

The Babinski sign is a simple test that involves stroking the sole of the foot with a blunt-ended instrument to check the response of the toes. This is the plantar reflex — plantar relating to the sole of the foot. Normally, when this reflex is triggered, the toes should curl under or flex downward toward the sole.

If the big toe points upward, and the smaller toes fan out, this is an “upgoing plantar” response — also known as the Babinski sign, named after the neurologist Joseph Babinski who first described it. It is normal to find this response in babies, whose nervous systems are undergoing development and not capable of all the motor functions of an adult.

In adults, finding the Babinski sign tells a different story. It often indicates that a stroke is affecting the brain's control over the feet. Other reasons may include conditions like multiple sclerosis or, rarely, drug intoxication. Interestingly, in some healthy individuals, the Babinski sign can even show up during deep sleep.

The scope of conditions that can affect our feet is not limited to just diabetes, kidney failure, and thyroid disorders. In fact, they can be important indicators of our overall health. Therefore, it is crucial to have regular checks on our feet and seek medical advice if we notice any pain, discoloration, or rashes.

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Dan Baumgardt is a senior lecturer at the School of Physiology, Pharmacology and Neuroscience at the University of Bristol in the United Kingdom. He does not have any financial ties to companies or organizations that could be influenced by this article. Baumgardt has not disclosed any additional affiliations beyond his academic role.

Editor's P/S:

The article highlights the importance of observing our feet for signs of underlying health conditions. From viral infections to cardiovascular diseases and neurological disorders, the appearance of our feet can provide valuable clues. For instance, hand, foot, and mouth disease manifests as raised spots on the extremities, while blue toe syndrome, characterized by discoloration and pain, indicates a blockage in blood supply to the feet.

Furthermore, the Babinski sign, an abnormal response of the toes to a stimulus, can indicate a stroke or other neurological issues. These examples emphasize the need for regular foot checks and prompt medical attention if any concerns arise. By paying attention to the health of our feet, we can gain insights into our overall well-being and seek appropriate treatment early on.