What to know about paresthesia
Paresthesia is numbness or a burning feeling that occurs most often in the extremities, such as the hands, arms, legs, or feet, but that can happen elsewhere in the body as well.
It is the same “pins and needles” feeling that happens when someone sits on their leg or foot for too long. Usually a temporary sensation, it is caused when pressure is placed on the nerve that supplies a limb. Once that pressure is relieved, the discomfort goes away.
Some people have chronic or long-term paresthesia, which can be a sign of a more serious nerve injury or condition.
Fast facts on paresthesia
Here are some key points about paresthesia. More detail and supporting information is in the main article.
- Causes can include stroke, diabetes, or multiple sclerosis.
- If due to a pinched nerve, the symptoms can be intermittent or constant and may be reversible.
- Treatment options depend on the cause of the paresthesia.
- Anyone with ongoing paresthesia should see a doctor, especially if the symptoms are new, constant, or not attributed to anything else.
There are many different causes of chronic paresthesia, including:
- multiple sclerosis
- tumor in the spinal cord or brain
- high levels of vitamin D or other vitamins
- high blood pressure
- nerve injury
- compressed, or pinched, nerve
A pinched nerve occurs when there is too much pressure put on it by the surrounding tissue. This pressure causes paresthesia in the area supplied by that nerve, and its function is interrupted. A pinched nerve can happen anywhere in the body, such as the face, the neck, the wrist, or the back.
A herniated disk in the lower spine can cause pain in the back, leg or foot on the affected side.
Carpal tunnel syndrome is a pinched nerve in the wrist that causes numbness and tingling in the fingers.
The symptoms of paresthesia or a pinched nerve include:
- tingling or a “pins and needles” sensation
- aching or burning pain
- numbness or poor feeling in the affected area
- feeling that the affected area has “fallen asleep”
- prickling or itching feeling
- hot or cold skin
The symptoms can be constant or intermittent. Usually, these sensations occur in the affected area but may spread or radiate outward.
Some factors increase the risk of having a pinched nerve:
- Gender: Women are more likely to get carpal tunnel syndrome, possibly due to a narrower nerve canal.
- Obesity: Extra weight can put pressure on nerves.
- Pregnancy: Weight and water gain associated with pregnancy can cause swelling and pressure on nerves.
- Thyroid disease: This puts a person at risk for carpal tunnel syndrome.
- Diabetes: Having diabetes can cause nerve and tissue damage.
- Rheumatoid arthritis: This causes inflammation, which can also compress nerves in the joints.
- Prolonged bed rest: Lying down for extended periods can cause nerve compression and increase the risk for paresthesia.
- Overuse: People who have jobs or hobbies that require repetitive motion of the hands, elbows or feet are at a higher risk for a pinched nerve, paresthesia or nerve damage.
Anyone can get a pinched nerve, and most people will have experienced paresthesia at some point or another.
To diagnose paresthesis, a doctor will first take a medical history and ask questions about a person’s symptoms.
Next, the doctor will likely perform a physical examination and, depending on the findings, may recommend tests, including.
- Nerve conduction study: This measures how fast nerve impulses travel in the muscles.
- Electromyography (EMG): To look at the electrical activity of how nerves and muscles interact.
- Magnetic resonance imaging (MRI): This can be used to look at the different areas of the body in high detail.
- Ultrasound: Used to produce images of the body, this can be applied to smaller areas to look for nerve compression or damage, such as occurs in carpal tunnel syndrome.
The type of test that the doctor prescribes will depend on the results of these tests, plus a person’s symptoms and medical history.