The following information contains links to the source documents, as we become aware of new information we will try to add to this list. medical disclaimer - website disclaimer
Research Articles and Information:
The following information contains links to the source documents, as we become aware of new information we will try to add to this list. medical disclaimer - website disclaimer
THE LONG-TERM OUTCOME OF ORTHOSTATIC TREMOR - Orthostatic tremor is a progressive disorder with increased disability although tremor frequency is unchanged over time. In most cases, orthostatic tremor represents an isolated syndrome. Drug treatments are unsatisfactory but surgery may hold promise.
Shaking on Standing: A Critical Review Here, we provide a critical review of the clinical spectrum of shaking on standing, along with demonstrative electrophysiological recordings of some of these conditions.
Primary orthostatic tremor is an exaggeration of a physiological response to instability. In this study, EMG was recorded from tibialis anterior in healthy subjects who were made unsteady through vestibular galvanic stimulation or leaning backwards. Under these conditions, a peak at approximately 16 Hz was seen in the coherence between the left and right tibialis anterior. This bilateral coherence was absent when the subjects activated the same muscles when not unsteady. These data indicate the existence of a physiological system involved in organising postural responses under circumstances of imbalance and characterised by a highly synchronised output at approximately 16 Hz. In addition, the results suggest that the core abnormality in POT may be an exaggerated sense of unsteadiness when standing still, which then elicits activity from a 16-Hz oscillator normally engaged in postural responses. Mov Disord 2003 Feb
A retrospective study of the clinical and electrophysiological characteristics of 32 patients with Orthostatic Myoclonus . Conclusions: OM has some similarities to OT, including causing "shaky legs" subjectively in standing older patients. Novel data from this work include that, as in OT, OM essentially abates when patients remove their weight from their legs. This shared isometric phenomenon may reflect that OT and OM are on a pathophysiological continuum. Further, many patients who complain of their legs "shaking" while standing may have neither OT nor OM. Surface electromyography may be a useful adjunct in extrapolating patients complaining of "shaky legs."
Evidence for a non-orthostatic origin of orthostatic tremor The aim of this study was to determine if orthostatic tremor is invariably associated with the orthostatic and weight bearing conditions in the arms and legs, and to investigate the features of orthostatic tremor under different levels of peripheral loading. Shows tremors in a supine position (lying face up) with isometric contraction of arms and legs.
Body Tremors Have A Genetic Cause The latest issue of The American Journal of Human Genetics now reveals that researchers from Montreal University and its affiliated CHU Sainte-Justine and CHUM hospitals have managed to link some cases of Essential Tremor (ET) to a specific genetic problem.
Slow Orthostatic Tremor can persist when walking backwards - Classically orthostatic tremor and the associated symptom of intense unsteadiness disappear with ambulation1. Here we describe a patient with cerebellar atrophy who presented with slow orthostatic tremor, which disappeared when walking forwards, but persisted when walking backwards.
Shaky legs? Think POT! .... three cases seen in a general neurology clinic over a 15-month period to highlight the typical clinical features which should alert clinicians to the possibility of this diagnosis.
Characterizing orthostatic tremor: a study of 56 patients : The age at OT onset distribution had a single peak and was a decade later than essential tremor (ET), which is bimodal. Symptomatic leg tremor was ubiquitous, but OT affected the arms in 50%, head (20%), trunk (16%) and voice and tongue (both 7%) of cases.
Primary orthostatic tremor in giant breed dogs The tremors typically begin in the lower aspects of the legs, but can also involve the muscles of the head and face. The tremors are usually first apparent at a young age (1-2 years).
Quality of life in patients with orthostatic tremor :We conclude that OT strongly impacts on QoL (quality of life). The results highlight the importance of recognizing and treating depression in patients with OT.
Developing Unique Brain Maps To Assist Surgery And Research "Microscopic images inside the living brain will transform diagnosis and treatment of diseases such as multiple sclerosis, Parkinson's disease, Alzheimer's disease and Huntington's disease," A/Prof Egan said.
Steam Train Sign in Slow Orthostatic Tremor: The helicopter sign is a pathognomonic sign of orthostatic tremor constituting the auditory correlate of the characteristic high frequency (13 to 18 Hz) tremor in the legs upon standing. 1 The auditory correlate of low frequency tremor in slow ortho- static tremor is however unknown.
Shaking on Standing: A Critical ReviewHere, we provide a critical review of the clinical spectrum of shaking on standing, along with demonstrative electrophysiological recordings of some of these conditions.
A New teaching video has been posted on Neurology.org “Orthostatic Tremor: The Helicopter Sign”, this video contains the audio of the sound of the tremor, the chart of the sEMG and shows the legs of the patient under test. click to read more....
Diagnosis is usually obtained based on clinical evaluation combined with surface electromyogram (EMG). Surface EMG contains a high-frequency component -- 16 to 18 Hz. Misdiagnosis is common and many patients are initially thought to have a non-organic (psychogenic) balance disorder. Frequency domain analysis of surface EMG or sway traces can diagnose this condition (Yarrow et al, 2001). As a similar tremor can be induced in normal persons via vestibular stimulation (Sharott et al, 2003), conditions that cause imbalance should be considered in addition.
Link: CONCLUSION: Analysis of power spectra from posturographic recordings is a simple, quick method to screen for primary orthostatic tremor. The condition might be more common than previously assumed. It is important to identify patients with primary orthostatic tremor because they might be misdiagnosed and left without treatment.
The timing of primary orthostatic tremor bursts has a task-specific plasticity…..This analysis reveals a linkage between these oscillations with a complex and task-specific pattern of phase delays and suggests that these phase delays may reflect the activity of normally occurring neural networks or oscillators involved in postural control.
Shaky-Leg Syndrome and Vitamin B12 Deficiency A 68-year-old man presented with a three-year history of trembling of the legs….Results of laboratory tests were remarkable only for a serum vitamin B12 level of 132 ng per liter (normal range, 222 to 753)….The association of shaky-leg syndrome with vitamin B12 deficiency in our patient might have been a coincidence. However, the fact that the tremor did not recur after discontinuation of clonazepam supports this association. There are a variety of treatments that visitors have reported in attempts to control this disorder, and the most current can be found and discussed on the user forum.
Additional research links can be found on the forum ...click to view.... If you have a published article and would like the OT Resource to link to it, please let us know.
** The information above contains links to the source documents, as we become aware of new information we will try to add to this list, we are only passing along this information and not making any conclusions about techniques used in diagnosis, misdiagnoses etc.
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