The spinal segmental myoclonus by viral radiculitis has been rarely reported and the pathophysiology remains to be elucidated. However, the hyperactivity of contiguous anterior horn neurons induced by viral irritation has been suggested to be a possible patho-mechanism. In general, spinal segmental myoclonus is not well-controlled by medication and the patient suffers from continuous involuntary movement. We recently experienced a case of spinal segmental myoclonus induced by herpes zoster radiculitis, and which was successfully relieved by epidural injections.
