Introduction
Dystonia is a type of movement disorder characterized by repetitive involuntary contractions of agonist and antagonist muscles. Dystonia is generally considered to be caused by dysfunction of the basal ganglia. Recent studies suggested that dystonia is also associated with the disorder of brainstem, but the pathologic mechanism is not clearly known. There have been only a few case reports about dystonia as a consequence of focal brainstem lesions with the limited presentation of detailed management strategy. Here, we report a case of hemidystonia with abnormal posture and impaired proprioception after pontine hemorrhage, effectively treated with clonazepam and benztropine.
Case
A 45-year-old man without known medical history was referred to our hospital with sudden onset of right side weakness on 18th, April, 2020 and about 2.7cm sized acute intracerebral hemorrhage in the bilateral pons was confirmed by brain computed tomography. After conservative management, he was transferred from Neurology to Rehabilitation medicine department on 6th, May, 2020. On the initial evaluation, manual muscle test demonstrated no motor weakness and Korean Mini Mental State Examination score was 30/30. He showed abnormal posture and dystonic movement in his right hand and foot, which worsened when trying to stand up or grasp objects. Finger twisting and involuntary writhing movements were continuously observed and he could not utilize his right hand for activities of daily livings(ADLs). Manual Function Test(MFT) score of affected side was 18/32 and Functional Independence Measure(FIM) score was 57/126. He showed remarkably impaired proprioception, slightly impaired light touch sensation and intact pain sensation in his right extremities. He could not stand alone and Berg Balance Scale(BBS) was 0/54.
For the management of dystonia, we applied clonazepam 0.25mg/day on the 24th day after onset, the dose was increased to 0.5mg/day after 3 days and benztropine 0.5mg/day was added after 8 days. Comprehensive rehabilitation treatment was also performed including sensory stimulation, proprioceptive motor control, standing balance training, gait training, fine motor training and bimanual ADLs training. During the month of treatment, symptoms gradually improved. His abnormal dystonic movements were only observed to less than 30 percent of the initial level. His right hand and fingers have been softened, thus, he could control them voluntarily. On the one month follow up evaluation, MFT score improved from 18 to 24/32 and FIM score improved from 57 to 90/126. He could gait independently about 10 meters indoors, and his BBS improved from 0 to 31/54.
Conclusion
This is a rare case of contralateral hemidystonia caused by pontine hemorrhage and application of clonazepam and benztropine was helpful to treat dystonia. |
|
Fig. 1. The Brain Computed Tomography Shows Acute Pontine Hemorrhage
Fig. 2. The Sagital T1-weighted Magnetic Resonance Imaging Shows Pontine Hemorrhage
Fig. 3. Changes in FIM, BBS and MFT Scores During a Month of Treatment FIM : Functional Independence Measure, BBS : Berg Balance Scale, MFT : Manual Function Test
|
