Involuntary jerking of lower half of the body (spinal myoclonus).

A 55 years old, hypertensive, diabetic lady presented with sudden onset jerky movement of lower trunk and legs. It was present both in awake and sleep and got aggravated by mental stress as well as sensory stimulation. Examination revealed rhythmic jerks affecting muscles of lower abdomen and legs. The lower limbs had normal muscle bulk and power, increased tone, exaggerated deep tendon reflexes, bilateral flexor plantar response with normal sensory autonomic and cerebellar function. Investigations including CSF study, MRI of dorsal spine and NCV were normal. A combination therapy with tizanidine, baclofen and clonazepam induced gradual improvement within 6 weeks.