Sensorimotor Polyneuropathy - Peripheral Neuropathy

Peripheral neuropathy is a loss of function in the peripheral nerves. These are the nerves that branch out from the brain and spinal cord.

What is going on in the body?

Peripheral neuropathy occurs when the peripheral nerves are damaged. The damage is usually caused by a loss of myelin, which is the protective coating of the nerve. Myelin increases the speed at which information can be sent through a nerve. Direct trauma to a nerve can also cause peripheral neuropathy. The injury can block the flow of information along the nerve.

What are the causes and risks of the condition?

Peripheral neuropathy can be caused by a number of factors.

Diseases that can cause the neuropathy include:

Conditions that may cause neuropathy include:

Peripheral neuropathy can also be caused by pressure on the nerve caused by the following:

Carpal tunnel syndrome is an example of peripheral neuropathy that is caused by entrapment. The median nerve is trapped between the wrist bones and a ligament. The pressure on the nerve causes loss of function in the wrist and hand.

What are the signs and symptoms of the condition?

Symptoms of peripheral neuropathy are seen in the body area(s) supplied by the damaged nerve. Damage to the median nerve at the wrist, for example, may cause symptoms in the wrist and hand. Symptoms in involved areas may include the following:

How is the condition diagnosed?

Diagnosis of peripheral neuropathy begins with a medical history and physical exam. The healthcare provider may detect muscle weakness and decreased sensation. The provider may order tests, including the following:

What can be done to prevent the condition?

Some cases of peripheral neuropathy can be prevented by avoiding or controlling the underlying problem. Individuals with diabetes can lower their risk by controlling their blood glucose levels. Following sports safety guidelines for children, adolescents, and adults can help prevent some injuries. Following a heart-healthy diet can lower a person's risk for atherosclerosis.

What are the long-term effects of the condition?

Without treatment, peripheral neuropathy will worsen over time. The individual may lose muscle function and sensation. There may even be muscle wasting, or atrophy. The person may have chronic pain that worsens at night. Skin injuries may not heal properly and may become infected. If tissue dies, the person may need amputation of a limb.

What are the risks to others?

Peripheral neuropathy is not contagious and poses no risk to others.

What are the treatments for the condition?

Treatment of peripheral neuropathy varies, depending upon the underlying problem. Following are some examples:

If an individual has significant pain, medications may be recommended. These include the following:

Someone who has peripheral neuropathy is at increased risk for injury. Decreased sensation increases the risk for burns. A person with muscle weakness may fall easily. Following are some measures to prevent injuries.

The person should examine all areas of decreased sensation on a daily basis. Any cuts, bruises, or pressure sores should be reported to the healthcare provider.

What are the side effects of the treatments?

Medications used to treat neuropathy may cause stomach upset or allergic reactions. Some can also cause drowsiness, dry mouth, and constipation.

What happens after treatment for the condition?

If the underlying cause is effectively treated, the person may recover some or all of the nerve function. Recovery is slow and complications are common. The person may lose sensation and movement to a part of the body.

How is the condition monitored?

Any new or worsening symptoms should be reported to the healthcare provider.

Author:James Broomfield, MD
Date Written:
Editor:Ballenberg, Sally, BS
Edit Date:05/31/01
Reviewer:Adam Brochert, MD
Date Reviewed:05/04/01