Depending on the type of fibers they contain, three types of nerves can be identified: motor, sensory, and vegetative or autonomic.
Motor nerves are responsible for voluntary movements. When, for example, we open a door or run, our motor nerves are at work.
The sensory nerves allow us to feel the pain, the vibrations, the touch, to recognize the shapes of the objects only by touching them, and to know the position of parts of our body in space.
The autonomic nerves control involuntary functions (ie not under will control), such as breathing, heart rate, blood pressure, digestive and sexual functions. They always work, independently, both when we are awake and when we sleep.
Although many neuropathies affect, in different degrees, all three types of nerve fibers, in some cases only one or two types of fibers are affected and there is therefore talk of purely or predominantly motor, sensitive, or vegetative neuropathies.
The disease of a single peripheral nerve is called mononeuropathy. Mononeuropathies affect single nerves in well-defined areas and are often the result of a traumatic injury, local compression (with "crushing" of the nerve) or inflammatory or ischemic processes. The symptomatology is therefore localized and limited to the area of innervation of the injured nerve. Examples of mononeuropathies are carpal tunnel syndrome, and Bell's palsy.
If the disorders affect two or more nerves in distinct areas we speak of multiple mononeuritis. This generally occurs during systemic diseases, such as diabetes or rheumatological diseases.
Depending on whether motor, sensory or both nerves are affected, it is called motor, sensory, or mixed neuropathy.
WHAT ARE THE SYMPTOMS?
Some neuropathies begin suddenly, others gradually over a period of years. The symptoms depend on the type of nerve fibers involved (motor, sensitive, vegetative) and their location, but in most cases they manifest themselves with weakness, tingling and pain.
CAUSES OF NEUROPATHY
Two large groups of neuropathies can be distinguished: hereditary (caused by genetic anomalies) and acquired (that is, due to diseases acquired during the course of life).