The long-term outcome of orthostatic tremor (original) (raw)

Primary orthostatic tremor: further observations in six cases

Journal of Neurology, 1992

The clinical and physiological features of six new patients with primary orthostatic tremor are described. We suggest that use of the term primary orthostatic tremor be confined to the clinical syndrome in which unsteadiness when standing is the predominant complaint and accompanied by characteristic electrophysiological findings of a rapid (frequency around 16 Hz), regular leg tremor which is not influenced by peripheral feedback, is synchronous between homologous leg muscles, and in certain postures of the upper limbs, between muscles of the arm and leg. The fast frequency of muscle activity in primary orthostatic tremor of the legs causes unsteadiness when standing (presumably due to partially fused muscle contraction) but only a fine ripple of muscle activity is visible. In contrast, the slower frequency of other leg tremors, for example essential tremor, results in obvious leg movement which is evident in many leg postures, is variable over time and can be reset by a peripheral nerve stimulus. Essential tremor and orthostatic tremor do not respond to the same therapies, suggesting differences in the pharmacological profiles of the two conditions. Accordingly, there are clinical, physiological and pharmacological differences between primary orthostatic and essential tremor. Whether these factors are sufficient to regard these tremors as separate conditions is discussed.

Orthostatic tremor: An electrophysiological analysis

Movement Disorders, 1998

Orthostatic tremor (OT) is a clinically defined syndrome of leg tremor while standing. Controversy surrounds whether OT is a distinct syndrome or is an essential tremor (ET) variant. We report two patients with OT. Electrophysiological testing included polymyography, accelerometry, nerve conduction, and evoked potential studies. The effects of various maneuvers and body positions on the tremor were assessed. The findings included rapid (15-17 Hz) lower-extremity tremor burst frequency evoked by standing but not by walking or swaying; rapid upper-extremity burst pattern synchronous with lower-extremity bursts; and failure of electrical stimulation or mental concentration to "reset" the tremor. Additionally, there was the novel finding of accelerometric recordings in the legs

Orthostatic tremor: report of two cases and an electrophysiological study

Acta Neurologica Scandinavica, 1989

Two patients with legs tremor present on standing, but none on walking or sitting, are reported. Tremor was not exclusive of orthostatism and was also evoked by strong tonic contraction of leg muscles. Synchronous EMG bursts were recorded in antagonistic muscle groups at 8-10 Hz in the first patient and at 16 Hz in the second. EMG activity was synchronous in corresponding muscles of both legs. The occurrence of EMG activity was not influenced by stimulation of nerve afferent fibers. We suggest that this movement disorder may be an exaggeration of physiological tremor due to synchronization of motor units by spontaneous oscillations in central structures.

Pathogenesis of Primary Orthostatic Tremor: Current Concepts and Controversies

Tremor and other hyperkinetic movements (New York, N.Y.), 2017

Orthostatic tremor (OT), a rare and complex movement disorder, is characterized by rapid tremor of both legs and the trunk while standing. These disappear while the patient is either lying down or walking. OT may be idiopathic/primary or it may coexist with several neurological conditions (secondary OT/OT plus). Primary OT remains an enigmatic movement disorder and its pathogenesis and neural correlates are not fully understood. A PubMed search was conducted in July 2017 to identify articles for this review. Structural and functional neuroimaging studies of OT suggest possible alterations in the cerebello-thalamo-cortical network. As with essential tremor, the presence of a central oscillator has been postulated for OT; however, the location of the oscillator within the tremor network remains elusive. Studies have speculated a possible dopaminergic deficit in the pathogenesis of primary OT; however, the evidence in favor of this concept is not particularly robust. There is also limi...

Comprehensive, blinded assessment of balance in orthostatic tremor

Parkinsonism & related disorders, 2018

Orthostatic Tremor (OT) is a movement disorder characterized by a sensation of unsteadiness and tremors in the 13-18 Hz range present upon standing. The pathophysiology of OT is not well understood but there is a relationship between the sensation of instability and leg tremors. Despite the sensation of unsteadiness, OT patients do not fall often and balance in OT has not been formally assessed. We present a prospective blinded study comparing balance assessment in patients with OT versus healthy controls. We prospectively enrolled 34 surface Electromyography (EMG)-confirmed primary OT subjects and 21 healthy controls. Participants underwent evaluations of balance by blinded physical therapists (PT) with standardized, validated, commonly used balance scales and tasks. OT subjects were mostly female (30/34, 88%) and controls were majority males (13/20, 65%). The average age of OT subjects was 68.5 years (range 54-87) and for controls was 69.4 (range 32-86). The average duration of OT...

Long-term course of orthostatic tremor in serial posturographic measurement

Parkinsonism & Related Disorders, 2015

Objective: Primary orthostatic tremor (OT) is a rare neurological disease of unknown pathophysiology characterized by a high-frequency tremor mainly of the legs when standing. The aim of this study was to examine its long-term course by subjective estimation and objective recording by serial posturography and to obtain further standardized epidemiological and clinical data on patients with OT. Methods: A clinical cohort of 37patients with the diagnosis of primary OT was screened for this longitudinal follow-up study. Eighteen patients consented to participate. During study visit all patients underwent a standardized neurological examination and completed subjective scales and scores. Posturographic recordings at follow-up were compared to prior clinical posturographic measurements in 15cases. Results: In our cohort the mean duration of symptoms was 14.1 ± 6.8 years. Subjectively, 78% of patients reported progression of the disease. Posturographic data (5.4 ± 4.0 years) revealed a significant increase of the total sway path (standing on firm ground with eyes open) from 2.4 ± 1.3 to 3.4 ± 1.4 m/min (p ¼ 0.022) and of the total root mean square values from 9.8 ± 4.3 to 12.4 ± 4.8 mm (p ¼ 0.028). None of these observations are explained by aging of the patients. Mean frequency of the tremor did not change over time (14.7 ± 1.9 Hz vs. 14.9 ± 2.0 Hz at follow-up). Clinically, most patients had signs of cerebellar dysfunction and a substantial portion also showed proprioceptive deficits in the long-term course. Conclusions: This long-term follow-up study indicates, that primary OT is a progressive disorder. Furthermore, the clinical observation of cerebellar dysfunction in most OT patients in the long-term course might indicate an important role of the cerebellum in its pathophysiology.

Tremors and its determinants: a 7-years study at a secondary care hospital

JPMA. The Journal of the Pakistan Medical Association, 2011

To evaluate the cause, frequency and determinants of tremors at secondary care settings. A hospital based cross-sectional study for seven years (2002-2009) was carried out at Sindh Govt. Hospital (SGH) Liaqatabad No.10, Karachi. Sample size was 403 and sampling technique was Convenience sampling. A data collection form was designed and all essential variables were recorded regarding age, gender, residence, complaints and their duration, education status, profession, co-morbid and investigations performed. The results were analyzed using SPSS 16.0. Out of 403 patients 247 (61.5%) were males and 156 (38.5 %) were females. The mean age of the patients was 55.9 +/- 14.2 years. The male to female ratio was 2: 1.6. Enhanced physiological tremor was the most frequent diagnosis. Among whom, females of 40-60 years were mostly affected. Essential tremors were mainly coarse in amplitude, whereas commonest fine tremors were diagnosed as Enhanced Physiological tremor. Evaluation of patients with...

Diagnosis and Treatment of Common Forms of Tremor

Seminars in Neurology, 2011

Tremor is the most common movement disorder presenting to an outpatient neurology practice and is defined as a rhythmical, involuntary oscillatory movement of a body part. The authors review the clinical examination, classification, and diagnosis of tremor. The pathophysiology of the more common forms of tremor is outlined, and treatment options are discussed. Essential tremor is characterized primarily by postural and action tremors, may be a neurodegenerative disorder with pathologic changes in the cerebellum, and can be treated with a wide range of pharmacologic and nonpharmacologic methods. Tremor at rest is typical for Parkinson's disease, but may arise independently of a dopaminergic deficit. Enhanced physiologic tremor, intention tremor, and dystonic tremor are discussed. Further differential diagnoses described in this review include drug-or toxin-induced tremor, neuropathic tremor, psychogenic tremor, orthostatic tremor, palatal tremor, tremor in Wilson's disease, and tremor secondary to cerebral lesions, such as Holmes' tremor (midbrain tremor). An individualized approach to treatment of tremor patients is important, taking into account the degree of disability, including social embarrassment, which the tremor causes in the patient's life.

Tremor analysis in two normal cohorts

Clinical Neurophysiology, 2004

Objective: Quantitative tremor analyses using almost identical methods were compared between two independent large normal cohorts, to separate robust measures that may readily be used diagnostically from more critical ones needing lab-specific normalization. Methods: Hand accelerometry and surface EMG from forearm flexors and extensors were recorded with (500 and 1000 g) and without weight loading under postural conditions in 117 and 67 normal volunteers in two different specialty centers for movement disorders in Germany. Results: Tremor amplitude (total power) and frequency fell within a similar range but differed significantly. A significant reduction of tremor frequency under 1000 g weight load (. 1 Hz), and a lack of rhythmic EMG activity at the tremor frequency in around 85-90% of the recordings were robust findings in both centers. Conclusions: The differences in frequency and total power indicate that these measures critically depend on the details of the recording conditions being slightly different between the two centers. Thus each lab needs to establish its own normative data. We estimate that at least 25 normal subjects have to be recorded to obtain normal values. The reduction of tremor frequency under load and lacking tremor-related EMG activity were well reproducible allowing a differentiation of physiological from low amplitude pathological tremor. Significance: This study provides a framework for more standardized tremor analyses in clinical neurophysiology.

A patient with tremor, part 1: making the diagnosis

Canadian Medical Association Journal, 2011

A 58-year-old woman presented with shaking of her left hand that had started insidiously and progressively worsened over the past few years. She also complained of stiffness in her left arm. The shaking was more pronounced when she rested her hand. Although the shaking decreased when she outstretched her arms, it persisted when she walked (Appendix 1, video available at www.cmaj.ca /lookup /suppl /