National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Primary orthostatic tremor


Other Names:
OT; Shaky leg syndrome; Orthostatic tremor, primary; OT; Shaky leg syndrome; Orthostatic tremor, primary; POT See More
Categories:
Primary orthostatic tremor (POT) is a rare, progressive movement disorder that causes unsteadiness when standing still, due to a rapid tremor affecting the legs and trunk.[1][2] The tremor is sometimes described as having “shaky legs,” and it improves or disappears when walking, sitting, or lying down.[1][2][3] This may cause people with POT to attempt to sit again or walk immediately after standing, for fear of falling.[2][3] People with POT may also experience tiredness, physical exhaustion, muscle stiffness or weakness, and/or pain.[3][4] Symptoms tend to gradually worsen over time and may lead to the need for a mobility aid such as a cane, scooter, or wheelchair.[1][3][4]

The diagnosis of POT relies on a clinical exam as well as a specialized test called a surface electromyogram (EMG), which measures electrical activity in the muscles.[3] The cause of POT is not completely understood, but the disorder is thought to involve dysfunction of the brain’s ability to regulate nerve signals that control muscle activity.[1][3] Some researchers believe that POT is a type of essential tremor.[3]

Treatment usually involves medications used to control seizures (anticonvulsants) such as clonazepam or gabapentin. In some cases, treatment may include medications used for Parkinson’s disease (levodopa or pramipexole), and/or botulinum toxin (Botox) injections in the leg muscles. More than one therapy may be tried before finding one that helps.[3] POT does not appear to alter life expectancy. However, quality of life for people with POT may be severely impaired due to physical symptoms, fear of falling, and uncertainty about the course of the disorder.[1]
Last updated: 1/25/2019

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 5 |
Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
EMG abnormality 0003457
Muscle spasm 0003394
Tremor 0001337
30%-79% of people have these symptoms
Myalgia
Muscle ache
Muscle pain
[ more ] 		0003326
5%-29% of people have these symptoms
Abnormality of extrapyramidal motor function 0002071
Showing of 5 |
Last updated: 7/1/2020

Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
Differential diagnoses based on clinical and EMG findings include slow orthostatic tremors (4-12 Hz) that have been described in patients with Parkinson's disease and parkinsonism, cerebellar lesions and atrophy.
Visit the Orphanet disease page for more information.

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Primary orthostatic tremor. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Primary orthostatic tremor. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.

  1. Czernecki V, Broussolle E, Bonnet C, Falissard B, Jahanshahi M, Vidailhet M, Roze E. Health-Related Quality of Life Is Severely Affected in Primary Orthostatic Tremor. Front Neurol. January 15, 2018; 8:747. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5775514/.
  2. Lenka A, Pal PK, Bhatti DE, Louis ED. Pathogenesis of Primary Orthostatic Tremor: Current Concepts and Controversies. Tremor Other Hyperkinet Mov (N Y). November 17, 2017; 7:513. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5712672/.
  3. Jankovic J. Primary Orthostatic Tremor. National Organization for Rare Disorders (NORD). 2017; http://www.rarediseases.org/rare-disease-information/rare-diseases/byID/1133/viewAbstract.
  4. Living with orthostatic tremor. National Tremor Foundation. https://tremor.org.uk/orthostatic-tremor.html. Accessed 1/17/2019.