Upper Limb Function but Not Proprioception is Impaired in Essential Tremor: A Between-Groups Study and Causal Mediation AnalysisShow others and affiliations
2023 (English)In: TREMOR AND OTHER HYPERKINETIC MOVEMENTS, ISSN 2160-8288, Vol. 13Article in journal (Refereed) Published
Abstract [en]
Background: Essential tremor (ET) is characterized by abnormal oscillatory muscle activity and cerebellar involvement, factors that can lead to proprioceptive deficits, especially in active tasks. The present study aimed to quantify the severity of proprioceptive deficits in people with ET and estimate how these contribute to functional impairments.Methods: Upper limb sensory, proprioceptive and motor function was assessed in individualswith ET (n = 20) and healthy individuals (n = 22). To measure proprioceptive ability, participants discriminated the width of grasped objects and the weight of objects lifted with the wrist extensors. Causal mediation analysis was used to estimate the extent that impairments in upper limb function in ET was mediated by proprioceptive ability.Results: Participants with ET had impaired upper limb function in all outcomes, and had greater postural and kinetic tremor. There were no differences between groups in proprioceptive discrimination of width (between-group mean difference [95% CI]: 0.32 mm [-0.23 to 0.87 mm]) or weight (-1.12 g [-7.31 to 5.07 g]). Causal mediation analysis showed the effect of ET on upper limb function was not mediated by proprioceptive ability.Conclusions: Upper limb function but not proprioception was impaired in ET. The effect of ET on motor function was not mediated by proprioception. These results indicate that the central nervous system of people with ET is able to accommodate mild to moderate tremor in active proprioceptive tasks that rely primarily on afferent signals from muscle spindles.
Place, publisher, year, edition, pages
UBIQUITY PRESS LTD , 2023. Vol. 13
Keywords [en]
essential tremor; proprioception; function; causal mediation; upper limb
National Category
Physiotherapy
Identifiers
URN: urn:nbn:se:liu:diva-191372DOI: 10.5334/tohm.731ISI: 000908669500001PubMedID: 36644368OAI: oai:DiVA.org:liu-191372DiVA, id: diva2:1732702
Note
Funding Agencies|Motor Impairment Program grant from the National Health and Medical Research Council (NHMRC) [1055084]
2023-01-312023-01-312025-02-11