What Causes Numbness in the Legs?

Leg numbness is a loss of feeling in your legs, often accompanied by other sensations like tingling or pins-and-needles pain or discomfort. It can be caused by a variety of health conditions.

Leg numbness can be caused by a range of common and rare health conditions, from diabetes to spinal deformities. These conditions may be related to nerves or circulation, or something else like an injury or lifestyle factors.

Nerve-Related Causes

• Peripheral neuropathy
• Herniated disc

“With tingling and numbness below the knees, it can suggest diabetes,” especially if someone hasn’t been to the doctor in years, says Lukasz Jaros, MD, a family medicine physician at Northwestern Medicine in Chicago. In that case, Dr. Jaros says, he’ll order an A1C test to check for diabetes.

A rare but serious cause of leg numbness can be a tumor, infection, or other abnormality that presses on nerves in the spinal cord itself. This may be the case when someone has pain shooting down both legs. “We would potentially be sending them to the emergency room for imaging and potentially a neurosurgical intervention” to prevent permanent spinal nerve damage, says Jaros.

Circulatory Causes

The following blood vessel conditions can cause leg numbness:

• Peripheral arterial disease (PAD)
• Deep vein thrombosis (DVT), a type of blood clot

Systemic Health Conditions

Some relatively rare causes of leg numbness include the following conditions:

• Multiple sclerosis (MS)
• Vitamin deficiencies, especially vitamin B12

Injury and Physical Factors

Certain other physical issues can cause leg numbness, especially:

• Peripheral nerve compression
• Injury or trauma
• Positional nerve compression

Sometimes, the positioning of your body — such as crossing your legs a certain way — can compress nerves and cause temporary numbness. In that case, sensation should return within a few minutes of adjusting your position. “If it happens once or twice, it’s usually not something that needs to be treated,” says Jaros.

Certain Medications

• Heart and blood pressure drugs
• Cancer or chemotherapy drugs
• Certain infection-fighting drugs
• Seizure treatments
• HIV/AIDS treatments

• Arsenic
• Illegal drugs
• Glue sniffing

In many cases, numbness in legs is accompanied by other symptoms that can help you and your doctor figure out what might be happening in your body. It’s also important to note exactly where in your legs or other areas numbness occurs, and any other sensations that you experience.

“They should definitely describe their baseline status — if the numbness is completely new, did this come out of nowhere or was it associated with a recent illness or trauma?” says Alluri.

• Pain or discomfort
• Tingling
• Burning
• Changes in temperature sensation
• Muscle weakness
• Loss of balance
• Difficulty walking

It’s a good idea to see a doctor any time you experience new or worsening numbness in your legs, to figure out and potentially treat what’s causing the numbness.

• Any possible injury or trauma that may have caused your numbness
• Bladder or bowel changes
• Numbness in your face, or involving an entire arm or leg
• Muscle weakness or paralysis
• Confusion
• Dizziness
• Speech difficulty
• Sudden, severe headache

These situations may indicate a serious problem with your brain or spine, including potentially a stroke or brain injury, says Alluri.

Your doctor will try to determine what’s causing your leg numbness by getting a detailed medical history from you, and performing any tests or physical examinations as needed.

“Number one is providing a really clear history,” involving your doctor asking a series of questions about your symptoms, says Alluri. “It’s a physician’s job to really listen,” he says, and decide what next steps to take.

Depending on the suspected cause of your numbness, your doctor may recommend any of the following tests or procedures:

• Magnetic resonance imaging (MRI) of your head or spine
• X-ray imaging of your spine
• Ultrasound imaging of your leg or legs
• Electromyography (EMG) and nerve conduction studies
• Blood tests

X-ray imaging of the spine can be useful when someone has or may have osteoporosis, Jaros says. In this case, a bone fracture in the spine may lead to nerve compression.

Blood tests are also useful to check for conditions including diabetes, anemia, electrolyte abnormalities, and certain sexually transmitted diseases — all of which can potentially contribute to leg numbness, says Jaros.

Any treatments prescribed for leg numbness will depend on the underlying cause.

Peripheral Neuropathy

For peripheral neuropathy, “Sometimes you can’t find a cause, or there isn’t really a treatment,” says Alluri. “So then it’s symptom management, and you can use different kinds of medications” to help reduce unpleasant sensations.

• Over-the-counter pain relievers
• Anti-seizure drugs
• Lidocaine cream or patches
• Certain antidepressants
• Spinal cord stimulation devices

Once neuropathy has started in diabetes, it often can’t be reversed. But with good diabetes control, worsening of symptoms can be prevented. And good glucose control in people with diabetes can prevent the development of neuropathy in the first place.

Herniated Disc

Circulation Issues

A number of lifestyle measures may help prevent leg numbness, particularly when it comes to peripheral neuropathy or a herniated disc.

Maintaining a healthy body weight can help prevent problems like a herniated disc from forming in your spine. “The more weight you put on your low back, the higher risk you are for degenerative pathology,” says Alluri.

Getting up and moving regularly can help prevent nerve compression due to positional factors. “The more active we are, that’s going to alleviate some of the pressure on the nerves,” says Jaros. He also recommends positioning computer monitors at eye level, to help prevent a stooped posture that can contribute to nerve compression.

The Takeaway

• Numbness in your legs can be caused by many health conditions, including peripheral neuropathy, a herniated disc, or nerve damage from an injury.
• Seeing a doctor is important in order to find the cause of your leg numbness. Treatments may address the underlying cause or help alleviate your symptoms.
• Maintaining a healthy body weight, not smoking, and not drinking in excess may help prevent health issues that can cause leg numbness.