Hemiballismus

Striatal neuronal loss correlates with clinical motor impairment in Huntington's disease

Huntington's disease (HD) is characterized clinically by chorea, motor impairment, psychiatric manifestations, and dementia. Atrophy of the striatum is the neuropathological hallmark of HD, and previous studies have suggested that striatal atrophy correlates more closely with motor impairment than with chorea. Motor impairment, as measured by motor impairment score, correlates with functional disability in HD patients, but chorea does not. In this study, we investigated the relation between neuronal loss and these motor features. We conducted neuropathological and stereologic assessments of neurons in putamen and subthalamic nuclei in HD patients and age-matched controls. In putamen, we estimated the total number and volume of medium spiny neurons labeled with dopamine- and cAMP-regulated phosphoprotein 32 kDa (DARPP-32). In subthalamic nuclei, we estimated the total number of neurons on hematoxylin & eosin/luxol fast blue stains. In putamen of HD, immunohistochemistry showed DARPP-32 neuronal atrophy with extensive disruption of neurites and neuropil; stereologic studies found significant decreases in both the number and size of DARPP-32 neurons; we also detected a significant reduction of overall putamen volume in HD patients, compared to controls. In subthalamic nuclei, there was a mild, but significant, neuronal loss in the HD group. The loss of neurons in putamen and subthalamic nuclei as well as putaminal atrophy were significantly correlated with severity of motor impairment, but not with chorea. Our findings suggest that neuronal loss and atrophy in striatum and neuronal loss in subthalamic nuclei contribute specifically to the motor impairment of HD, but not to chorea.

Successful treatment of posttraumatic hemiballismus with intrathecal baclofen therapy

Intrathecal baclofen (ITB) therapy is widely used in the management of spastic hypertonia and dystonia resulting from a multitude of conditions that present with upper motor neuron syndrome signs, such as cerebral palsy, stroke, brain and spinal injuries, and multiple sclerosis. We report successful management of posttraumatic hemiballismus and dystonia with ITB in a 43-yr-old man who sustained a traumatic brain injury secondary to an assault in 1978. He subsequently developed hemiballismus in the right lower limb and dystonia of the distal right upper limb spreading proximally to involve the shoulder. The ballistic movement of the lower limb was severe enough to cause the patient to fall out of his chair and limit his ability to perform activities of daily living safely. He had been on various oral medications and received botulinum toxin and phenol injections, but none alleviated the symptoms. The patient elected to receive the ITB pump. Before ITB, he had an average of 10-12 ballism episodes of the right lower limb per hour. During observed episodes, the right hip would flex up to about 90 degrees, with a fully extended knee. After ITB pump implantation and upward dose titration, the frequency of ballistic right leg movements decreased to about three per day, and the right hip flexed to only 30 degrees. In addition, there was increased ability to isolate individual distal joint movements in the right lower limb. The patient currently receives 202.4 microg/day ITB and continues to benefit almost 6 yrs after ITB pump implantation. This report highlights the emerging role of ITB in managing movement disorders other than dystonia spastic hypertonia and dystonia.