Postanoxic symptomatic oscillatory myoclonus

Two young patients with a history of birth anoxia and cerebral palsy developed paroxysmal irregularly oscillating muscle jerks at rest and during voluntary movement. Electrophysiologic studies revealed short bursts of alternating activity at 4 to 6 Hz in antagonist muscles. The absence of time-locked EEG discharges suggests a subcortical origin for this unusual form of myoclonus. A comparison is made between this and previously reported conditions with a similar paroxysmal burstlike nature.