What movement disorder is characterized by slow, involuntary writhing movements?

Athetosis is a movement disorder marked by slow, involuntary writhing movements, typically affecting the hands, arms, and sometimes the legs. Patients with athetosis exhibit movements that are often continuous and fluid, making it challenging to maintain a fixed posture or perform purposeful actions. These movements may be exacerbated by emotional states or purposeful movements, and they can interfere with everyday activities.

In contrast, dystonia is characterized by sustained muscle contractions and abnormal postures rather than the slow, writhing movements seen in athetosis. Myoclonus involves sudden, brief jerking contractions of muscles, and chorea consists of rapid, irregular, and unintentional movements that can resemble dance-like motions. Understanding these distinctions helps to clarify why athetosis is the correct label for the described movement disorder.