Degeneration of the axon slows or blocks conduction at the point of the degeneration. In some cases, no detectable cause of the neuropathy can be identified. Pressure injury may be caused by direct injury or compression of the nerve cell by other nearby body structures. Compression can also be caused by pressure from casts, splints, braces, crutches, or other appliances. Prolonged periods in cramped positions may cause nerve injury.
Entrapment neuropathy includes compression of a nerve where it passes through a narrow space.
Systemic causes of neuropathy include disorders affecting the connective tissues of the nerves, disorders affecting the blood supply to the nerve cells, hereditary conditions, metabolic or chemical disorders, and other disorders that damage nerve tissue. A detailed history may be needed to determine the possible cause of the neuropathy. They may include various blood tests, X-rays, scans, or other tests and procedures. The cause should be identified and treated whenever possible. This may include control of blood-sugar levels for diabetics, abstinence from alcohol, nutritional supplements, surgical decompression or other surgical treatments, or medical treatment of conditions.