Peripheral
Peripheral neuropathy, a result of damage to the nerves located outside of the brain and spinal cord (peripheral nerves), often causes weakness, numbness and pain, usually in the hands and feet. It can also affect other areas and body functions including digestion, urination and circulation.
Peripheral
Your peripheral nervous system sends information from your brain and spinal cord (central nervous system) to the rest of your body. The peripheral nerves also send sensory information to the central nervous system.
People with peripheral neuropathy generally describe the pain as stabbing, burning or tingling. In many cases, symptoms improve, especially if caused by a treatable condition. Medications can reduce the pain of peripheral neuropathy.
Peripheral neuropathy can affect one nerve (mononeuropathy), two or more nerves in different areas (multiple mononeuropathy), or many nerves (polyneuropathy). Carpal tunnel syndrome is an example of mononeuropathy. Most people with peripheral neuropathy have polyneuropathy.
Seek medical care right away if you notice unusual tingling, weakness or pain in your hands or feet. Early diagnosis and treatment offer the best chance for controlling your symptoms and preventing further damage to your peripheral nerves.
Claudication is pain in the legs or arms that occurs while walking or using the arms. The pain is caused by too little blood flow to the legs or arms. Claudication is usually a symptom of peripheral artery disease, in which the arteries that supply blood to the arms or legs, usually the legs, are narrowed. The narrowing is usually due to a buildup of fatty deposits (plaques) on the artery walls.
If peripheral artery disease gets worse, pain may occur during rest or when lying down. The pain may interrupt sleep. Hanging the legs over the edge of the bed or walking may temporarily relieve the pain.
Peripheral artery disease (PAD) is plaque buildup in your leg arteries. Your leg arteries carry oxygen and nutrient-rich blood from your heart to your arms and legs. Other names for this are peripheral vascular disease or peripheral arterial disease.
Shaped like hollow tubes, arteries have a smooth lining that prevents blood from clotting and promotes steady blood flow. When you have peripheral artery disease, plaque (made of fat, cholesterol and other substances) forms gradually inside your artery walls. Slowly, this narrows your arteries. This plaque is also known as atherosclerosis.
Although PAD is a different condition from coronary artery disease, the two are related. People who have one are likely to have the other. A person with PAD has a higher risk of coronary artery disease, heart attack, stroke or a transient ischemic attack (mini-stroke) than someone without peripheral artery disease. A person with heart disease has a 1 in 3 chance of having peripheral artery disease in their legs.
You have the ability to prevent peripheral artery disease (PAD) or keep it from getting worse by making lifestyle changes. Keep all of your follow-up appointments with your healthcare provider and vascular specialist, and take the medicines they prescribe for all of your conditions. Knowing the warning signs of PAD complications helps you know when to ask for help, too.
Peripheral neuropathy refers to the many conditions that involve damage to the peripheral nervous system, which is a vast communications network that sends signals between the central nervous system (the brain and spinal cord) and all other parts of the body.
More than 20 million people in the U.S. are estimated to have some form of peripheral neuropathy, but this figure may be significantly higher as not all people with symptoms of neuropathy are tested for the disease and tests currently do not look for all forms of neuropathy.
Symptoms can range from mild to disabling, but are rarely life-threatening. The symptoms depend on the type of nerve fibers affected and the type and severity of damage. Symptoms may develop over days, weeks, or years. In some cases, symptoms improve on their own and may not require advanced care. Unlike nerve cells in the CNS, peripheral nerve cells continue to grow throughout life.
Smoking constricts the blood vessels that supply nutrients to the peripheral nerves and can worsen neuropathic symptoms. Exercise can deliver more blood, oxygen, and nutrients to far-off nerve endings, improve muscle strength, and limit muscle atrophy. Self-care skills in people with diabetes and others who have an impaired ability to feel pain can alleviate symptoms and often create conditions that encourage nerve regeneration. Strict control of blood glucose levels can reduce neuropathic symptoms and help people with diabetic neuropathy avoid further nerve damage.
Local anesthetics and related drugs that block nerve conduction may help when other medications are ineffective or poorly tolerated. Medications put on the skin (topically administered) are generally appealing because they stay near the skin and have fewer unwanted side effects. Lidocaine patches or creams applied to the skin can be helpful for small painful areas, such as localized chronic pain from mononeuropathies such as shingles. Another topical cream is capsaicin, a substance found in hot peppers that can desensitize peripheral pain nerve endings. Doctor-applied patches that contain higher concentrations of capsaicin offer longer term relief from neuropathic pain and itching, but they worsen small-fiber nerve damage. Weak over-the-counter formulations also are available. Lidocaine or longer acting bupivacaine are sometimes given using implanted pumps that deliver tiny quantities to the fluid that bathes the spinal cord, where they can quiet excess firing of pain cells without affecting the rest of the body. Other drugs treat chronic painful neuropathies by calming excess signaling.
Transcutaneous electrical nerve stimulation (TENS) is a noninvasive intervention used for pain relief in a range of conditions. TENS involves attaching electrodes to the skin at the site of pain or near associated nerves and then administering a gentle electrical current. Although data from controlled clinical trials are not available to broadly establish its efficacy for peripheral neuropathies, in some studies TENS has been shown to improve neuropathic symptoms associated with diabetes.
NINDS-funded research ranges from clinical studies of the genetics and the natural history of hereditary neuropathies to discoveries of new cause and treatments for neuropathy, to basic science investigations of the biological mechanisms responsible for chronic neuropathic pain. Together, these diverse research areas will advance the development of new therapeutic and preventive strategies for peripheral neuropathies. Understanding the causes of neuropathy provides the foundation for finding effective prevention and treatment strategies.
Rapid communication between the peripheral nervous system and the central nervous system often depends on myelination, a process through which special cells called Schwann cells create an insulating coating around axons. Several NINDS-funded studies focus on understanding how myelin protein and membrane production and maintenance in Schwann cells is regulated and how mutations in genes involved in these processes cause peripheral neuropathies. Schwann cells play a critical role in the regeneration of nerve cell axons in the peripheral nervous system. By better understanding myelination and Schwann cell function, researchers hope to find targets for new therapies to treat or prevent nerve damage associated with neuropathy.
In inflammatory peripheral neuropathies such as Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy (CIDP), the body's immune system mistakenly attacks peripheral nerves, damaging myelin and weakening signaling along affected nerves. NINDS-supported researchers hope to better understand how antibodies to cell membrane components cause peripheral nerve damage and how the effects of these antibodies can be blocked. Researchers are also studying how mutations in the Autoimmune Regulator (AIRE) gene in a mouse model of CIDP cause the immune system to attack peripheral nerves. NINDS research has helped discover that some types of small-fiber polyneuropathy appear to be immune-caused, particularly in women and children.
NINDS-supported researchers are also exploring the use of tissue engineered from the cells of humans with peripheral neuropathy as models to identify specific defects in the transport of cellular components along axons and the interactions of nerves with muscles. Such tissue engineering approaches may eventually lead to new therapeutics for peripheral neuropathies.
Consider participating in a clinical trial so clinicians and scientists can learn more about peripheral neuropathy and other nerve disorders. Clinical research uses human volunteers to help researchers learn more about a disorder and perhaps find better ways to safely detect, treat, or prevent disease.
For information about participating in clinical research visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for people with peripheral neuropathy at Clinicaltrials.gov, a database of current and past trials, some of which have research results.
There are several different kinds of peripheral neuropathies that stem from a variety of causes. They range from carpal tunnel syndrome (a traumatic injury common after chronic repetitive use of the hands and wrists, such as with computer use) to nerve damage linked to diabetes.
Damage to a single peripheral nerve is called mononeuropathy. Physical injury or trauma such as from an accident is the most common cause. Prolonged pressure on a nerve, caused by extended periods of being sedentary (such as sitting in a wheelchair or lying in bed), or continuous, repetitive motions, can trigger a mononeuropathy.
Polyneuropathy accounts for the greatest number of peripheral neuropathy cases. It occurs when multiple peripheral nerves throughout the body malfunction at the same time. Polyneuropathy can have a wide variety of causes, including exposure to certain toxins such as with alcohol abuse, poor nutrition (particularly vitamin B deficiency), and complications from diseases such as cancer or kidney failure. 041b061a72