Orthostatic Hyperkinetic Disorders in Subacute Sclerosing Panencephalitis – A Novel Observation

Sakoon Saggu; Deepa Dash; Animesh Das; Arunmozhimaran Elavarasi

doi:10.5334/tohm.1277

Orthostatic Hyperkinetic Disorders in Subacute Sclerosing Panencephalitis – A Novel Observation

Tremor and Other Hyperkinetic Movements

Volume 16 (2026): Issue 1

By: Sakoon Saggu , Deepa Dash , Animesh Das and Arunmozhimaran Elavarasi

Open Access

|Sep 2026

Abstract

Background: Subacute sclerosing panencephalitis (SSPE) is a progressive, often fatal inflammatory encephalitis caused by persistent measles virus infection of the central nervous system. The neurological manifestations of SSPE are well characterised, encompassing cognitive decline, periodic myoclonic jerks, and often relentless progression.

Case Report: We report a case of a 14-year-old male with SSPE who developed bilateral lower limb shaking and knee buckling, with associated loss of quadriceps tone on standing. These features resulted in recurrent falls and necessitated supported ambulation.

Discussion: To our knowledge, this combination of orthostatic limb shaking and loss of tone in the context of SSPE has not been previously described in the literature. This case expands the recognised phenotypic spectrum of SSPE.

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Articles in this issue

DOI: https://doi.org/10.5334/tohm.1277 | Journal eISSN: 2160-8288

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Language: English

Page range: 52 - 52

Submitted on: Jul 31, 2026

Accepted on: Sep 4, 2026

Published on: Sep 18, 2026

Published by: Ubiquity Press

In partnership with: Paradigm Publishing Services

Keywords:

Subacute sclerosing panencephalitis,

SSPE,

Orthostatic myoclonus,

Orthostatic hyperkinetic disorders,

Orthostatic Tremor

© 2026 Sakoon Saggu, Deepa Dash, Animesh Das, Arunmozhimaran Elavarasi, published by Ubiquity Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 16 (2026): Issue 1