Why Do Your Legs Sometimes Feel Numb? The Science Behind It

Have you ever experienced a tingling, burning, or crawling sensation in your legs or feet? This is called numbness, and it can happen for various reasons. Sometimes, it’s just a temporary effect of sitting or crossing your legs for too long. Other times, it can be a sign of a more serious condition that affects your nerves or blood vessels. In this blog post, we will explore some of the common causes of leg numbness, how they affect your body, and what you can do about them.

Paresthesia: When Your Leg Falls Asleep

One of the most common causes of leg numbness is paresthesia, which is also known as your leg falling asleep. This happens when you put too much pressure on a nerve in your leg, which prevents it from sending signals to your brain. This can happen if you sit or cross your legs for a long time, wear tight shoes, or injure your foot or ankle. The nerve compression usually goes away when you change your position and relieve the pressure. You may feel a pins-and-needles sensation as the blood flow and nerve function return to normal.

Paresthesia is usually harmless and temporary, but it can also be a symptom of a more serious condition that affects your nerves, such as diabetes, multiple sclerosis, or spinal cord injury. If you experience frequent or persistent numbness in your legs or feet, you should see a doctor to rule out any underlying problems.

Sciatica: When Your Back Pinches Your Nerve

Another common cause of leg numbness is sciatica, which is a condition that affects your sciatic nerve. This is the longest and thickest nerve in your body, and it runs from your lower back through your hips and buttocks and down your legs. If this nerve gets pinched or irritated by a herniated disc, bone spur, muscle spasm, or injury, it can cause pain, weakness, tingling, or numbness in your leg. Sciatica usually affects only one side of your body and can vary in intensity and duration.

Sciatica can sometimes go away on its own with rest and home remedies, such as ice packs, anti-inflammatory drugs, or stretching exercises. However, if your symptoms last more than a week, interfere with your daily activities, or are accompanied by bladder or bowel problems, you should seek medical attention. Your doctor may prescribe stronger painkillers, steroid injections, physical therapy, or surgery to relieve the pressure on the nerve.

Diabetic Neuropathy: When Your Sugar Damages Your Nerves

If you have diabetes, you may be at risk of developing diabetic neuropathy, which is a type of nerve damage caused by high blood sugar levels. This can affect any part of your body, but it often starts in your toes and feet and then moves up your legs. According to the American Diabetes Association¹, about half of all people with diabetes experience some form of neuropathy or nerve damage.

Diabetic neuropathy can cause numbness or tingling in your feet and legs, as well as pain, sensitivity to touch, muscle weakness, balance problems, foot sores or infections. These symptoms can get worse at night and make it hard to walk or sleep. If left untreated, diabetic neuropathy can lead to serious complications such as ulcers, gangrene, amputation, joint damage, or even death.

The best way to prevent or delay diabetic neuropathy is to keep your blood sugar levels under control with medication, diet, exercise and regular check-ups. Your doctor may also prescribe medications to help with pain, tingling, or sensitivity. Some of these medications include anti-inflammatory drugs, antidepressants, anti-seizure drugs, or topical creams. In some cases, you may need other treatments such as nerve stimulation, acupuncture, or surgery to relieve your symptoms or prevent complications.

Multiple Sclerosis: When Your Immune System Attacks Your Nerves

Multiple sclerosis (MS) is a condition that affects your central nervous system, which includes your brain and spinal cord. In MS, your immune system mistakenly attacks the protective coating around your nerve fibers, called myelin. This causes inflammation and damage to the nerves, which can interfere with the transmission of signals between your brain and body. This can result in various symptoms depending on which nerves are affected.

Numbness or tingling in the legs and feet is a common early symptom of MS. It can also affect your hands and arms and is called paresthesia. Other symptoms of MS include:

• vision problems
• fatigue
• muscle weakness or spasms
• balance or coordination problems
• bladder or bowel problems
• cognitive or emotional changes

MS is a chronic and unpredictable disease that can vary in severity and progression. There is no cure for MS, but there are treatments that can help manage the symptoms and reduce the frequency and severity of relapses. These treatments include medications that modulate the immune system, steroids that reduce inflammation, or drugs that target specific symptoms such as pain, spasticity, or bladder problems. You may also benefit from physical therapy, occupational therapy, speech therapy, or counseling to help you cope with the challenges of living with MS.

Other Causes of Leg Numbness

There are many other possible causes of leg numbness that are less common but still important to be aware of. Some of these include:

• Tarsal tunnel syndrome: This is a condition that affects the nerve that runs along the inside of your ankle and foot. It can cause numbness, tingling, burning, or pain in your foot and toes. It can be caused by injury, inflammation, arthritis, diabetes, or flat feet.
• Peripheral artery disease: This is a condition that affects the blood vessels that supply oxygen and nutrients to your legs and feet. It can cause reduced blood flow to your limbs, which can lead to numbness, pain, cramping, coldness, or skin changes in your legs and feet. It can be caused by atherosclerosis (buildup of plaque in the arteries), smoking, high blood pressure, high cholesterol, diabetes, or obesity.
• Stroke or transient ischemic attack: This is a condition that affects the blood supply to your brain. It can cause sudden numbness or weakness in one side of your body, including your leg or foot. It can also cause other symptoms such as confusion, slurred speech, vision problems, dizziness, or headache. It can be caused by a blood clot or bleeding in the brain.

If you have any of these conditions or suspect you may have them, you should seek immediate medical attention, as these can be life-threatening emergencies.

Conclusion

Leg numbness can be a bothersome and sometimes alarming symptom that can affect your quality of life. It can have various causes, ranging from harmless to serious. The most common cause is paresthesia, which is usually temporary and harmless. Other common causes include sciatica, diabetic neuropathy, and multiple sclerosis, which are chronic and require ongoing management. Less common but serious causes include tarsal tunnel syndrome, peripheral artery disease, and stroke or transient ischemic attack, which require urgent medical care.

If you have diabetes or any other condition that increases your risk of nerve damage or blood vessel problems, you should take good care of your health and monitor your blood sugar levels regularly. You should also check your feet and legs for any signs of injury or infection and wear comfortable shoes that fit well. If you notice any changes in your sensation or function in your legs or feet, you should consult your doctor as soon as possible. Early diagnosis and treatment can help prevent further damage and complications.

Leg numbness can be a challenge to live with, but with proper care and treatment, you can reduce its impact on your life and enjoy your daily activities.

Related Links:

• For more information on diabetic neuropathy, visit the American Diabetes Association website: https://www.diabetes.org/diabetes/complications/neuropathy
• For more information on multiple sclerosis, visit the National Multiple Sclerosis Society website: https://www.nationalmssociety.org/What-is-MS
• For more information on tarsal tunnel syndrome, visit the American Orthopaedic Foot & Ankle Society website: https://www.aofas.org/footcaremd/conditions/ailments-of-the-ankle/Pages/Tarsal-Tunnel-Syndrome.aspx
• For more information on peripheral artery disease, visit the American Heart Association website: https://www.heart.org/en/health-topics/peripheral-artery-disease