Multiple sclerosis (MS) is a potentially disabling disease of the brain and spinal cord (central nervous system).
In MS, the immune system attacks the protective sheath (myelin) that covers nerve fibers and causes communication problems between your brain and the rest of your body. Eventually, the disease can cause permanent damage or deterioration of the nerves

Conditions and symptoms
1. Numbness or weakness in one or more limbs that typically occurs on one side of your body at a time, or your legs and trunk
2. Electric-shock sensations that occur with certain neck movements, especially bending the neck forward (Lhermitte sign)
3. Tremor, lack of coordination or unsteady gait