Post-anoxic myoclonus: a case presentation and review of management in the rehabilitation setting

Post-anoxic myoclonus is a rare movement disorder manifested by diffuse action-triggered jerking movements that may result in significant disability. The incidence of this disorder is not clearly established, but over 122 cases have so far been reported in the literature. The pathogenesis is not entirely known, although it has been hypothesized that particular susceptibility of the Purkinje cells of cerebellum to anoxic injury may play a key role. A case is presented of an independently living 60-year-old woman admitted to the rehabilitation unit with diffuse myoclonus after sustaining a cardio-pulmonary arrest. She presented with severe jerking movements in all extremities with startle to noise and exacerbations upon attempting any purposeful actions. The patient's myoclonus was controlled by a variety of anti-epileptic medications. The patient initially responded to a combination of divalproex sodium and zonisamide, but relapsed in several weeks, requiring addition of levetriacetam and clonazepam. At a 1-year follow-up she demonstrated a significant improvement in ambulation and self-care activities. This case illustrates that, although patients with post-anoxic myoclonus cannot be fully cured, their quality of life can be significantly improved by rehabilitation interventions.