i did not know the name of it, but in the 1980s i took compazine for vomiting and had this as a 3 day long side effect. i had no control of where my neck went and it decided to bend sideways toward my shoulder. i now list compazine as one of my "allergies" so they don't ever give it to me again.

i have also had charlie horses in my chin occasionally. this is very painful.