I was diagnosed with Multiple Sclerosis in September 2007, and since then, I have been having numbness in my left leg sporadicly like an electric shock . It started to happen only when I tilted my head to the right and down toward my shoulder , but now, it can happen ANYTIME ... even while I am sleeping. While walking, this electric spasm halts my walking, as I cannot feel my leg and this sensation is overwhelming. My neurologist has gotten a recent MRI, but no results other than don t tilt your head that way . Please try to explain what I m feeling.