Arm posturing in a patient following stroke: Dystonia, levitation, synkinesis, or spasticity?

Background: Post-stroke movement disorders occur in up to 4% of stroke patients. The movements can be complex and difficult to classify, which presents challenges when attempting to understand the clinical phenomenology and provide appropriate treatment. Case Report: We present a 64-year-old male with an unusual movement in the arm contralateral to his ischemic stroke. The primary feature of the movement was an involuntary elevation of the arm, occurring only when he was walking. Discussion: The differential diagnosis includes dystonia, spontaneous arm levitation, synkinesis, and spasticity.We discuss each of these diagnostic possibilities in detail.