Your body has a complex network of nerves. One of your nervous system’s functions is to move your muscles. This encompasses motions over which you have control (voluntary) as well as those over which you have no control (involuntary).
When a component of the nervous system is injured or blocked, it might disrupt the signaling activity to a muscle or a set of muscles. This can result in muscle weakness or paralysis in the afflicted area/s. Damage to the neurological network can affect the brain, spinal cord, or one or more nerves, and can affect a limb on either the upper or lower part of the body.