Orthostatic Tremor

Shaky Legs Syndrome

1. Orthostatic tremor Ade Wijaya, MD November 2017

2. Outline Introduction Epidemiology Risk factors/etiology Pathophysiology Clinical manifestation Clinical examination Electromyography Diagnostic criteria Laboratory and Imaging Time course and progression Differential diagnosis Treatment Summary

3. Introduction Shaky legs syndrome   First coined in 1984 by Heilman E arlier descriptions of this entity date back to 1970 when Pazzaglia et al .  reported on three patients with a peculiar disorder only occurring on standing . Rare and intriguing   Unsteadiness when standing that is relieved when sitting or walking   Fast tremor of 13–18 Hz in the legs, trunk, and, sometimes, the arms P rimary (idiopathic) OT with or without postural arm tremor, and those with “OT plus,” in whom there are additional associated movement disorders, mainly parkinsonism. Adebayo, P. B. (2016). Orthostatic tremor: current challenges and future prospects.  DEGENERATIVE NEUROLOGICAL AND NEUROMUSCULAR DISEASE ,  6 , 17-24. Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

4. Epidemiology Onset: 6 th decade of life Female: male 4:1 Mostly sporadic Early onset OT Piboolnurak P, Yu QP, Pullman SL. Clinical and neurophysiologic spectrum of orthostatic tremor: case series of 26 subjects. Mov Disord. 2005;20(11):1455–1461 . Yaltho TC, Ondo WG. Orthostatic tremor: a review of 45 cases. Parkinsonism Relat Disord. 2014;20(7):723–725. Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

5. Risk Factors / Etiology Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

6. Pathophysiology Cerebello-thalamocorticospinal loop Central oscillator at posterior fossae Spinal cord may generate 16 Hz tremor T remulous disruption of proprioceptive afferent activity from the legs causing a cocontraction of the leg muscles to increase stability Dopaminergic system Neurodegenerative process Adebayo, P. B. (2016). Orthostatic tremor: current challenges and future prospects.  DEGENERATIVE NEUROLOGICAL AND NEUROMUSCULAR DISEASE ,  6 , 17-24. Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

7. Clinical Manifestation Unsteadiness during stance Tremor Leg pain Mostly also affecting other body parts Symptoms decrease by sitting, walking, or leaning against the wall Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

8. Clinical Examination High frequency tremor (13-18 Hz) Palpate gastrocnemius or quadriceps muscles (fine amplitude rippling) Easily felt than seen due to the high frequency Knee tremor Auscultation using a stethoscope of the gastrocnemius muscles can sometimes reveal a characteristic of barely audible noise akin to the sound of distant rotor blades of a helicopter. Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

9. Electromyography Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

10. Diagnostic Criteria

11. Laboratory and Imaging T hyroid function tests , Serum protein electrophoresis to rule out gammopathies , Vitamin B12 levels , Diagnostic studies to exclude Wilson’s disease (e.g. serum ceruloplasmin ), Brain MRI Lee HM, Kwon DY, Park MH, Koh SB, Kim SH. Symptomatic orthostatic tremor with progressive cognitive impairment in spinal cord lesions. Clin neurol Neurosurg. 2012;114:1329–1331. doi: 10.1016/j.clineuro.2012.03.021 .

12. Time Course and Progression Slowly progressive Spatial spread May proceed to develop other neurological conditions, especially PD and essential tremor . Other neurological disorders that have been documented in patients with OT include dementia with Lewy bodies, ataxic disorders, restless leg syndrome, orofacial dyskinesia, and periodic limb movement in sleep. QOL:Physical functioning, physical role limitations, social functioning, and emotional role limitations were the predominantly impaired domains of quality of life  depression Adebayo, P. B. (2016). Orthostatic tremor: current challenges and future prospects.  DEGENERATIVE NEUROLOGICAL AND NEUROMUSCULAR DISEASE ,  6 , 17-24.

13. Differential Diagnosis Essential tremor , Parkinson’s disease , Restless leg syndrome , Lumbar stenosis , Psychogenic balance disorders. Gerschlager W, Munchau A, Katzenschlager R, et al. Natural history and syndromic associations of orthostatic tremor: a review of 41 patients. Mov Disord. 2004;19:788–795. doi:  10.1002/mds.20132 . Piboolnurak P, Yu QP, Pullman SL. Clinical and neurophysiologic spectrum of orthostatic tremor: case series of 26 subjects. Mov Disord. 2005;20:1455–1461. Pfeiffer G, Hinse P, Humbert T, Riemer G. Neurophysiology of orthostatic tremor. Influence of transcranial magnetic stimulation. Electromyogr Clin Neurophysiol. 1999;39:49–53

14. Treatment Non-pharmacological: Portable stools A tripod walking stick Weight reduction Patient and family education Deep brain & spinal stimulation Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

15. Treatment Benito-León, J., & Domingo-Santos, Á. (2016). Orthostatic Tremor: An Update on a Rare Entity.  Tremor and Other Hyperkinetic Movements ,  6 , 411. http://doi.org/10.7916/D81N81BT

16. Summary Rare movement disorder Neurological vs non-motor features Treatment including non-pharmacological, pharmacological, and deep brain/spinal stimulation.

17. Thank you