December 8, 2022
Have you ever felt a prickling, tingling, or pins and needles sensation in your feet? You may be experiencing numbness in your toes. At times, it may even feel like your foot has fallen asleep, which occurs after keeping your foot in the same position for an extended duration.
What's happening in your foot and toes when they go numb? The underlying sensation is likely a result of peripheral neuropathy. Peripheral neuropathy is a catch-all term for more than 100 types of peripheral neuropathy. It refers to damage to the nervous system, which hinders the network of nerves that relays information to your brain.
There are various reasons why you experience numbness in your feet or your toes. Possible causes may include poor blood circulation or a byproduct of diabetes. The sensation may be numb; in other cases, you may not feel anything since your feet or toes lack feeling.
In this article, we outline five potential causes for why your feet or toes may go numb.
It's no secret that Canada experiences cold winters. Low temperatures and high humidity can make keeping your feet warm and dry difficult. That's why frostnip, and its successor, frostbite, are possible during Canada's winter months.
There are various degrees of skin and tissue damage due to cold. They are:
Frostnip is a mild cold exposure injury that doesn't cause permanent skin damage. A slight numbing sensation may occur during the frostnip stage and minor (but temporary) nerve damage. Frostnip should subside naturally by escaping the cold and returning to warmer temperatures.
Superficial frostbite is the second stage of cold damage to your toes. Your skin may feel warm, and you likely experience a more intense numbing or tingling sensation.
Deep frostbite is the third stage and most severe form of cold damage. You may experience total numbness and loss of sensation in your toes. The toe muscles and joints may no longer work, and you're at risk of permanently damaging the skin and nerves in your toes. Blisters form 24-48 hours after exposure. Afterwards, the area may turn black and harden as the tissue dies.
It's critical to recognize signs early. If you're outside for extended periods and feel your feet and toes are cold, it's time to head inside. Once you reach the numbing and tingling sensation, the damage begins to occur and will only worsen if not addressed. With minor forms of frostnip, the feeling will return to your feet and toes with no long-term effects. With frostbite, you risk permanent and irreversible damage.
Diabetes is a severe condition characterized by high blood sugar levels that can lead to blood flow and nerve issues. 3.4 million Canadians, or roughly 8.1% of the population, live with diabetes as of 2017–2018.
Regarding the foot, diabetes can complicate the nerves and blood vessels in two ways:
Diabetic neuropathy, a common long-term complication of Type-2 diabetes, causes nerve damage, leading to loss of sensation in the legs, feet and toes. A lack or loss of feeling in your feet and toes is dangerous as it can mask injuries, cuts, or other conditions.
In peripheral vascular disease, sugar accumulates in the bloodstream and can cause poor blood circulation. Blood vessels can narrow, block, and spasm due to PVD.
The best action for diabetes is to monitor your symptoms consistently. Further, a foot specialist can check for adequate circulation, signs of neuropathy, and risk for foot ulcers.
Both rheumatoid arthritis and rheumatoid vasculitis can cause numbing and tingling in your feet and toes. RA, an autoimmune disease where your immune system mistakenly attacks healthy cells in your body, can affect the nerves in your feet through inflammation and swelling.
Similarly, rheumatoid vasculitis targets the blood vessels in the feet, inhibiting their ability to transport blood. Reduced circulation can cause your feet and toes to be numb, creating a tingling sensation. Typically, one develops rheumatoid vasculitis after having RA for some time.
Tarsal tunnel syndrome
Tarsal tunnel syndrome is an ankle nerve condition that has downstream effects on the feet and toes. Analogous to carpal tunnel syndrome in our hands, tarsal tunnel syndrome occurs when a nerve becomes compressed—specifically, the posterior tibial nerve inside the ankle.
The tarsal tunnel itself is a narrow space next to the ankle bones. It's covered with thick ligaments and contains veins, arteries, tendons, and nerves (including the tibial nerve). When the tunnel becomes compressed, so does everything inside. Compression reduces blood circulation and puts pressure on the nerves that connect your feet and toes with the rest of your body.
The exact cause of tarsal tunnel syndrome can be tricky. In many cases, it's a variety of factors, including:
Bone spurs and cysts in the ankle
Acute ankle injuries
Tarsal tunnel syndrome symptoms include sharp, shooting pain, pins and needles, or a burning sensation on the inside of your foot, close to where your foot meets your ankle. The numbness may radiate to the toes as well.
You may suffer from Morton's neuroma if you've ever felt a sensation akin to having a pebble stuck in your shoe. This type of neuroma targets the base of the third and fourth toes. When the muscles and tendons become inflamed, the nerve becomes increasingly compressed, inhibiting its function.
You may develop Morton's neuroma with poor biomechanics - namely, overpronation (when your foot rolls too far inwards when walking or running). Biomechanical abnormalities unevenly distribute weight in your feet, adding too much (and too little stress) to certain parts of the foot. Over time, overpronation adds stress to the ball of the foot, causing it to thicken and become inflamed. As such, the foot's nerves can become compressed.
High heels (which promote poor biomechanics) are also a common contributing factor to Morton's neuroma.
The best course of action to treat Morton's neuroma is for a foot specialist to fit you with proper footwear or custom foot orthotics. Fixing your footwear and correcting your biomechanics will help distribute weight and stress in your feet more evenly.
Other causes of numb feet or toes
You may experience numb feet or toes for reasons other than those outlined above. For instance, your feet may fall asleep when you are asleep, and as a result, your feet may feel numb upon waking up. Being sedentary and keeping your feet and toes in the same position for extended periods may also create a numbing or tingling sensation.
Other, more uncommon causes may include:
Charcot-Marie-Tooth disease is a group of conditions that can cause nerve damage. It's genetic, and the mutations in the genes affect the nerves in your feet and the protective coating of your nerves, which can inhibit signals between your feet and brain.
Guillain-Barré syndrome is a rare disorder where your immune system attacks your body's nerves. You may experience weakness, tingling, and numbness when it affects your feet.
Vasculitis describes inflammation of blood vessels. Most types of vasculitis are rare. Vasculitis can cause a numb sensation in the feet due to a thickening blood vessel wall. As such, the thickening of the vessels can restrict blood flow to the limbs.
When in doubt, if you ever feel numb or have a tingling sensation in your feet for abnormal or irregular reasons, contact a professional for a proper diagnosis.