Movement Disorders in Multiple Sclerosis

Movement Disorders in Multiple Sclerosis: An Update

Background:

Multiple sclerosis (MS), a subset of chronic primary inflammatory demyelinating disorders of the central nervous system, is closely associated with various movement disorders. These disorders may be due to MS pathophysiology or be coincidental. This review describes the full spectrum of movement disorders in MS with their possible mechanistic pathways and therapeutic modalities.

Methods:

The authors conducted a narrative literature review by searching for ‘multiple sclerosis’ and the specific movement disorder on PubMed until October 2021. Relevant articles were screened, selected, and included in the review according to groups of movement disorders.

Results:

The most prevalent movement disorders described in MS include restless leg syndrome, tremor, ataxia, parkinsonism, paroxysmal dyskinesias, chorea and ballism, facial myokymia, including hemifacial spasm and spastic paretic hemifacial contracture, tics, and tourettism. The anatomical basis of some of these disorders is poorly understood; however, the link between them and MS is supported by clinical and neuroimaging evidence. Treatment options are disorder-specific and often multidisciplinary, including pharmacological, surgical, and physical therapies.

Discussion:

Movements disorders in MS involve multiple pathophysiological processes and anatomical pathways. Since these disorders can be the presenting symptoms, they may aid in early diagnosis and managing the patient, including monitoring disease progression. Treatment of these disorders is a challenge. Further work needs to be done to understand the prevalence and the pathophysiological mechanisms responsible for movement disorders in MS.

Movement Disorders in Multiple Sclerosis and Other Demyelinating Diseases: A Retrospective Review From a Tertiary Academic Center

BACKGROUND

Movement disorders (MDs) have been described in demyelinating diseases (DDs). However, data is lacking in the effective treatment of these MD as well as in a potential correlation between DD lesions localization and the phenomenology of the MD and its response to treatment.

METHODS

Retrospective review of 185 patients with MD and DD seen at our center over a period of 7 years. Clinical imaging, medications, and therapeutic responses to both MD and DD treatments were reviewed.

RESULTS

Of the 185 patients, 62 were excluded because of a diagnosis of spasticity without any other MD. One hundred twenty three patients with DD (75% female, age 48.8±12.8 y) had one or more MD. The most common MD was ataxia followed by isolated tremor. Forty-two patients (34%) received any treatment for MD, 29 (69%) of which responded at least partially to a first MD agent and 78.6% responded at least partially to a second or third agent. Responders to the first MD therapy were more likely to have a lesion in the basal ganglia or the cerebellum, and less likely to have a lesion in the brainstem or the spinal cord, but these results could be biased by a lower-than-expected frequency of tonic spasms in our series. No correlation between DD lesions localization and the phenomenology of the MD was discovered.

CONCLUSIONS

MD are common in DD and are frequently overlooked or undertreated. MD in this sample have a 69% therapeutic response to a first trial. Greater awareness of potential therapeutic options is needed to decrease disability.

Movement disorders in early MS and related diseases: A prospective observational study

BACKGROUND

Little is known about the true prevalence and clinical characteristics of movement disorders in early multiple sclerosis (MS) and related demyelinating diseases. We conducted a prospective study to fill this knowledge gap.

METHODS

A consecutive patient sample was recruited from the MS clinic within a 1-year-period. Patients diagnosed over 5 years before the study start date were excluded. Each eligible patient was interviewed by a movement disorder neurologist who conducted a standardized movement disorder survey and a focused examination. Each patient was followed prospectively for 1-4 follow-up visits. Movement disorders identified on examination were video-recorded and videos were independently rated by a separate blinded movement expert.

RESULTS

Sixty patients were included (56.6% female, mean age 38.3 ± 12.7 years). Eighty percent reported one or more movement disorders on the survey and 38.3% had positive findings on examination. After excluding incidental movement disorders (e.g., essential tremor), 58.3% were thought to have demyelination-related movement disorders. The most common movement disorders in a descending order were restless legs syndrome, tremor, tonic spasms, myoclonus, focal dystonia, spontaneous clonus, fasciculations, pseudoathetosis, hyperekplexia, and hemifacial spasm. The movement disorder started 5 months following a relapse on average but in 8 patients it was the presenting symptom of a new relapse or the disease itself. The majority of movement disorders occurred secondary to spinal (85.7%) or cerebellar/brainstem lesions (34.2%). Spinal cord demyelination was the only statistically significant predictor of demyelination-related movement disorders.

CONCLUSION

Movement disorders are more common than previously thought even in early MS. They typically begin a few months after spinal or brainstem/cerebellar relapses but may occasionally be the presenting symptom of a relapse.

Quantification characteristics of digital spiral analysis for understanding the relationship among tremor and clinical measures in persons with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is a degenerative neurological condition causing demyelination and neuronal loss. Tremor, a symptom of MS, is prevalent in 45.0-46.8% NARCOMS registrants. Although several tools to measure tremor exist, few outcomes are quantitative or regularly utilized clinically.

NEW METHOD

Introduction of a novel adaptation of the digital spiral drawing to find a quick, sensitive, and clinically useful technique, to predict tremor in persons with MS (pwMS). Digital spiral measures included: Segment Rate (SEGRT), Standard Deviation (SD) of Radial Velocity (VSD-R), SD of Tangential Velocity (VSD-T), SD of Overall Velocity (VSD-O), Mean Drawing Velocity (MNV-O) and Mean Pen Pressure Acceleration (MNA-P). Digital spiral measures were compared with the manual Archimedes Spiral (AS) drawing and the following clinical measures: Finger-Nose Test (FNT), presence of visually observed intention tremor (VOT), Nine-Hole Peg Test (NHPT), and Box and Block Test (BBT).

RESULTS

All clinical measures utilized demonstrated significant relationships with all digital variables, except VSD-R. The forward-stepwise regression revealed BBT accounted for the most variance, followed by SEGRT. Comparison with Existing Methods: SEGRT is more sensitive in detecting VOT and better for quantifying tremor than AS. BBT and SEGRT are optimal predictive measures for tremor.

CONCLUSIONS

SEGRT has stronger sensitivity and negative predictive value than AS in detecting VOT. All clinical measures (NHPT, FNT, BBT, and AS) were significantly associated with the digital variables (SEGRT, VSD-T, VSD-O, MNV-O, and MNA-P) except for VSD-R. After controlling for Patient Determined Disease Steps (PDDS), BBT and SEGRT are the best predictive measures for tremor.

Secondary paroxysmal dyskinesia in multiple sclerosis: Clinical–radiological features and treatment. Case report of seven patients

Secondary paroxysmal dyskinesias (SPDs) are short, episodic, and recurrent movement disorders, classically related to multiple sclerosis (MS). Carbamazepine is effective, but with risk of adverse reactions. We identified 7 patients with SPD among 457 MS patients (1.53%). SPD occurred in face ( n = 1), leg ( n = 2), or arm +leg ( n = 4) several times during the day. Magnetic resonance imaging (MRI) showed new or enhancing lesions in thalamus ( n = 1), mesencephalic tegmentum ( n = 1), and cerebellar peduncles ( n = 5). Patients were treated with clonazepam and then acetazolamide ( n = 1), acetazolamide ( n = 5), or levetiracetam ( n = 1) with response within hours (acetazolamide) to days (levetiracetam). No recurrences or adverse events were reported after a median follow-up of 33 months.