Most cases are idiopathic. Writer’s cramp frequently affects persons who write a great deal or perform other repetitive hand movements such as typing. Approximately 5% of patients have a positive family history of a similar condition. Five to ten percent report an accident or injury to the hand or arm immediately preceding the onset of symptoms. Rare causes include C6 ruptured disk, lithium use, basal ganglia or cortical tumors, arteriovenous malformations (AVMs), and stroke.