Distal median nerve dysfunction is a form of peripheral neuropathy that affects the movement of or sensation in the hands.
A common type of distal median nerve dysfunction is carpal tunnel syndrome.
Neuropathy - distal median nerve
Dysfunction of one nerve group, such as the distal median nerve, is called a mononeuropathy. Mononeuropathy means there is a local cause of the nerve damage. Diseases affecting the entire body (systemic disorders) can also cause isolated nerve damage.
This condition occurs when the nerve is inflamed, trapped, or injured by trauma. The most common reason is trapping (entrapment). Trapping puts pressure on the nerve where it passes through a narrow area. Wrist fractures may injure the median nerve directly. Or, it may increase the risk for trapping the nerve later on.
Inflammation of the tendons (tendonitis) or joints (arthritis) can also put pressure on the nerve. Some repetitive movements increase the chance of developing carpal tunnel entrapment. Women are more affected than men.
Problems that affect the tissue near the nerve or cause deposits to form in the tissue can block blood flow and lead to pressure on the nerve. Such conditions include:
In some cases, no cause can be found. Diabetes can make this condition worse.
Symptoms may include any of the following:
Your health care provider will examine your wrist and ask about your medical history. Tests that may be done include:
Treatment is aimed at the underlying cause.
If the median nerve is affected by carpal tunnel syndrome, a wrist splint can reduce further injury to the nerve and help relieve symptoms. Wearing the splint at night rests the area and decreases inflammation. An injection into the wrist may help with symptoms, but it won't fix the underlying problem. Surgery may be needed if a splint or medicines don't help.
For other causes, treatment may involve any of the following:
If the cause of the nerve dysfunction can be identified and treated, there is a good chance of full recovery. In some cases, there is some or complete loss of movement or sensation. Nerve pain may be severe and persist for a long time.
Complications may include:
Call your provider if you have symptoms of distal median nerve dysfunction. Early diagnosis and treatment increase the chance of curing or controlling symptoms.
Prevention varies, depending on the cause. In people with diabetes, controlling blood sugar may reduce the risk of developing nerve disorders.
For people with jobs that involve repetitive wrist movements, a change in the way the job is performed may be needed. Frequent breaks in activity may also help.
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