Check Out This Dog.

[shilala]

Here's the video.
This dog has Neuromyotonia, it's the same thing I have. I had no idea dogs could get it and I thought it was pretty amazing, even if it wasn't pertinent.
Neuromyotonia is kind of a "blanket term" that covers tons of things, including Isaac's Syndrome and PAM (Potassium Aggravated Myotonia), which I deal with daily.
The dog video is a really awesome example because he has little tiny muscles and it makes the Neuromyotonia look very defined. It'd much less defined in large muscle groups, like in my thigh.

The Neuromyotonia is actually completely painless, it just wears a person out because it's never-ending exercise, even sleeping.
What happens is that after a period of time, my muscles harden, staying stuck in a fully flexed position, and they won't let go. Then they continue to tighten until they tear themselves up. That hurts a bit, and takes a lot of healing.
It also causes what they call "periodic paralysis", because I lose control of all the body parts that no longer listen to what I tell them, beit my legs, arms, whatever.
It's all really kind of fascinating, I forgot until someone showed me that dog video. The people help control the dog with valium, which doesn't work for the spasms. It does get him pretty wasted, though.