Multiple Sclerosis Resource Centre
  • Home
  • MSRC Grand Opening 30/05/12
  • About MS
  • MSRC Services
  • Get Involved
  • MS Research News
  • MSRC Groups
  • Useful Resources
  • Welcome To Josephs Court, MS Centre Of Excellence
  • Advertising
  • Best Bet Diet Group
  • E-Newsletter
  • Contact Us
  • Investor in People
    You are here : Home » MS Research News » New Discoveries » Tremors And MS

    Tremors And MS

    A A A
    [Print this page]

    Share |

    Thalamic stimulation reduces permanent tremor in MS

    Intention TremorTremor in multiple sclerosis (MS) frequently improves during thalamic stimulation, even when limb strength is conserved, according to findings published in the April issue of the Journal of Neurology, Neurosurgery, and Psychiatry.

    “Permanent tremor reduction may simply reflect natural history,” reported Wesley Thevathasan, MD, of the Department of Neurology, John Radcliffe Hospital, Oxford, United Kingdom, and colleagues. “Alternatively, these findings appear consistent with the recent proposal that thalamic stimulation in MS might promote local ‘demyelinative lesioning.’”

    The researchers assessed tremor severity and limb strength preoperatively, early postoperatively (within one year), and late postoperatively (after three years) in 11 patients (eight women). The mean age of subjects was 38.7, and the mean duration of MS was 12.2 years. The mean Extended Disability Status Scale score was 7.2. Tremor had been predominant in the upper limbs and had occurred with posture and action. Furthermore, no patient had rest tremor, seven patients had bilateral tremor, and four had unilateral tremor.

    Tremor severity was rated with use of validated clinical scales while patients were on and off thalamic stimulation. After explantation, the investigators used MRI to examine the parenchyma surrounding three electrode tracts.

    During a final review (mean, 5.2 years) of patients, permanent tremor reduction was evident in 11 of the 18 upper limbs with tremor, and permanent tremor reduction often rendered stimulation redundant. Permanent tremor reduction could occur when limb strength was conserved and could arise remotely from the initial surgery, the authors suggested.

    “Permanent tremor reduction was significant (and universal) in limbs that received long-term (>2 years) effective (tremor suppressing) stimulation,” stated Dr. Thevathasan and colleagues. “Permanent tremor reduction was not a significant finding in limbs that had not received long-term, effective stimulation. Contralateral to a limb with permanent tremor reduction, MRI revealed a thalamic lesion adjacent to the electrode tract. Thalamic lesions were not identified contralateral to two limbs without permanent tremor reduction.

    “In this study, we found that it is common for MS tremor to permanently improve during long-term thalamic stimulation,”
    reported Dr. Thevathasan’s group. “Permanent tremor reduction occurred even when limb strength had been conserved. This suggests that tremor itself diminished rather than the expression of tremor being prevented by severe weakness, as had been suggested previously.

    “We observed permanent tremor reduction in a limb that had not received any contralateral stimulation,”
    the investigators continued. “However, spontaneous remission of MS tremor is not reported to be common. For example, in a study of 100 outpatients with MS, 31 had tremor, and none reported tremor remission.”

    The researchers believe that permanent tremor reduction is important to recognize from a clinical standpoint. “We would recommend that the persistence of tremor ‘off stimulation’ should be determined, to avoid unnecessary replacement of batteries nearing depletion,” they concluded.

    Suggested Reading
    Thevathasan W, Schweder P, Joint C, et al. Permanent tremor reduction during thalamic stimulation in multiple sclerosis. J Neurol Neurosurg Psychiatry. 2011;82(4):419-422.

    Source: Neurology Reviews Copyright © 2000-2011 Quadrant HealthCom Inc. (27/07/11)

    New discovery on cause of tremor

    TremorIn a new discovery, UK scientists have found a mechanism in the spine that counteracts the brain waves that produce tremor: they suggest the discovery could help around 1 million people in the UK who suffer from shakes and tremors.

    A paper on the research that led to the discovery, which was funded by the Wellcome Trust, and conducted by scientists at the Institute of Neuroscience at Newcastle University, Newcastle upon Tyne, was published online ahead of print in the 1 June issue of the Proceedings of the National Academy of Sciences.

    Most healthy individuals have experienced mild tremor, it is not uncommon when we feel tired, hungry or nervous, but more severe forms can be a symptom of neurological disease, including Parkinson's, Multiple Sclerosis and also Essential Tremor which is usually a disease of old age but it can also affect young people and it often leaves patients unable to walk unaided.

    Dr Stuart Baker, professor of movement neuroscience at Newcastle, told the media that:

    "We don't fully understand the brain systems causing these tremors but they can really have a massive impact on someone's quality of life. They lose their independence and can't do something as simple as make a cup of tea."

    Baker explained the approach they took in their research: instead of looking at why people have tremors, they decided to investigate why most people don't have them.

    He said that the part of the brain that controls movement produces brain waves that work at 10 cycles per second, so in theory everyone should have tremors that have that frequency.

    In fact we do, said Baker, but the tremor is so small that we don't notice it. So he and his team wondered if there was another process at work, one that countered the effect of the 10 cycles per second.

    For their study, Baker and colleagues used macaque monkeys: they taught them how to move their index finger backwards and forwards very slowly, which exacerbated the natural minor tremor that we humans and our primate relatives have in common.

    They then recorded nerve cell activity in the brain and spinal cord as the animals performed their slow finger movements.

    The results showed that not only was the rhythm of nerve cell activity in the brain and spinal cord oscillating at around the same frequency as the tremor, but that the spinal cord was exactly out of phase with the brain, effectively cancelling out its oscillations and thus reducing the size of the tremor.

    The researchers wrote that:

    "Convergence of antiphase oscillations from the SC [spinal cord] with cortical and subcortical descending inputs will lead to cancellation of approximately 10 Hz oscillations at the motoneuronal level."

    They concluded that:

    "This could appreciably limit drive to muscle at this frequency, thereby reducing tremor and improving movement precision. "

    Baker said there are many types of disease associated with tremor, and perhaps in some of these the controller in the spine malfunctions and that is what actually leads to tremor.

    In other diseases, he said, we already know the cause of tremor is a problem in brain regions that produce abnormally high oscillations.

    "But even then, the spinal system we have discovered will reduce tremors, making the symptoms much less severe than they would otherwise be," he added.

    The researchers suggested that the more we understand about how the spinal controller works, the better chance we have of developing treatments that adjust it to work better and thereby reduce the levels of tremor that patients experience and improve their quality of life.

    "Spinal interneuron circuits reduce approximately 10-Hz movement discontinuities by phase cancellation."
    Elizabeth R Williams, Demetris S Soteropoulos, and Stuart N Baker.
    PNAS, published ahead of print June 1, 2010.

    Source: Medical News Today © 2010 MediLexicon International Ltd (03/06/10)

    Related Items
    Abnormal Liver Tests and MS
    Aluminium and Multiple Sclerosis
    Antagonist compounds
    Antibodies, B Cells,T-Cell Activation, Immune Response
    Apolipoprotein D
    Bacteria & MS
    Biomarkers and MicroRNA
    Blood tests
    Bone Marrow Cells and MS Treatment
    Bowmann-Birk Inhibitor Concentrate (BBIC)
    Brain Atrophy, Lesion Loads, White and Grey Matter
    Brain Inflammation
    Brain Iron Deposits
    Calcium Binding Proteins
    Cerebro-Spinal Fluid & Spinal Cord
    Chronic Cerebrospinal Venous Insufficiency (CCSVI)
    CXCL1, 7, 12
    Cytokines & Chemokines
    Dendritic Cells
    Estrogen Receptors
    Fibrinogen, Mac-1 and Microglia
    Histamine and MS
    Hormones And MS Research
    Infections and Multiple Sclerosis Relapses
    JAK-STAT inhibitors
    Kallikrein 6
    Lipids & MS
    Medical Imaging
    Mycoplasmas And Bacteria
    N-acetylglucosamine (GlcNAc) & Glucosamine
    Natural Interferon Beta
    Natural Killer Cells
    Nerve and Brain Cell Research
    Olig 1 Gene Discovery
    Oligodendrocytes and Astrocytes
    Pesticides and Multiple Sclerosis
    Plasma Exchange
    Potential Viral Causes of MS
    Recombinant Human Erythropoietin
    Regeneration Research
    RNA and RNAi
    Synthetic Small Molecules
    Tetanus Vaccine and Possible MS Protection
    The Blood Brain Barrier
    Uric Acid
    Urinary Problems
    Vascular Function And MS
    Vision and MS

    Did you find this information useful? Would you like to comment on this page? Let us know what you think! We welcome all comments and feedback on any aspect of our website - please click here to contact us.