noun. Abnormal tonicity of muscle, characterized by prolonged, repetitive muscle contractions that may cause twisting or jerking movements of the body or a body part.

noun. A disabling neurological disorder in which prolonged and repetitive contractions of muscles cause jerking, twisting movements and abnormal postures of the body

"He was struck by a syndrome called dystonia, in which the brain loses the ability to control muscles, resulting in them spasming."

anastomosis  bronchus  cerebration  cytotoxicity  demyelination