Primary Orthostatic Tremor *, also known as Orthostatic Tremor (OT), is a neurological movement disorder, characterized by high frequency tremors, predominantly in the legs when in a standing position, and an immediate sense of instability.
Because of the speed of the contractions (13-18 Hz)** you may not recognize the problem as a tremor as compared to the more common essential tremor (4-7 Hz) or Parkinsons (3-6Hz) which produces a very visible movement.
Currently considered a rare disorder however, we are greatly under diagnosed and often misdiagnosed as other neurological problems such as Parkinson's, MS, ET, etc. Cause and cure is unknown. Orthostatic tremor was previously referred to as Shaky Leg Syndrome.
OT/POT is a complicated and difficult tremor disorder to understand. When we describe our symptoms to someone we generally do not complain of tremors as such because our main focus is on a sudden, unique, disabling event that happens to our legs when we attempt to do anything that requires us to remain in a standing position. What we feel in both legs simultaneously is extreme straining, unsteadiness and imbalance. The muscles in our legs become hard, our ankles feel weak and toes curl under as our legs fail to support us. We can stand for only a short period of time, in some cases only seconds. There is a feeling of panic to find a place to sit, or if possible, walk to gain some relief of our symptoms. Other areas of the body, such as trunk and arms may also be effected. This OT profile is a repeating cycle that happens all through our day. OT is an entity that is life changing and unrelenting.
Thank you to everyone that has contributed their experiences and thoughts to this website and forum. I know that it is very comforting for all of us to read these stories and to know that we are not alone in our journey. Each message increases our circle of friends and it may help to provide common pieces to the puzzle of this disease. There are two ways to include your story, you can leave it on the forum
or you can e-mail me directly with your permission to print it on the Visitors Page. Gloria
Le tremblement orthostatique primaire
Temblor ortostático: una entidad enigmática
Primaire orthostatische tremor
more information about Orthostatic tremor...
“...patients find it increasingly difficult to stand still due to sensations variably described as tremor, unsteadiness, and/or pain. Tasks such as waiting in line or doing dishes become troublesome, and patients find themselves needing to walk in place, continuously shift their weight from one leg to the other, or lean against a wall in order to reduce discomfort. OT may also be associated with muscle cramps, and patients will often describe subjective tremor elsewhere in the body, such as the lips, jaws, or hands. Significant disability and depression with substantial curtailing of activities can occur in severe cases.” Tremor Other Hyperkinet Mov (N Y). 2012; 2: tre-02-65-365-1
Primary orthostatic tremor is a rare neurologic condition of unknown origin characterized by a 10- to 20-Hz tremor in the legs while standing. Patients with primary orthostatic tremor usually complain of dizziness and unsteadiness that is relieved if they sit down or start to walk around. report”OT is a neurologic condition manifested by tremors, mainly in the legs, but also in the cranial structures, arms, and trunk” Clinical and Neurophysiologic Spectrum of Orthostatic Tremor: Case Series of 26 Subjects **Hz = oscillations or tremors per second. Primary Orthostatic Tremor is 13-18Hz.
SLOW ORTHOSTATIC TREMOR, which exhibits tremor <12Hz is discussed in this report. * The term Primary (refers to symptoms or a disease to which others are secondary) is often used interchangeably or in conjunction with idiopathic when describing Orthostatic Tremor. Idiopathic is defined as “...from an obscure or unknown cause” and Primary is defined as “a disease arising spontaneously and not associated with or caused by a previous disease or injury” . Primary Orthostatic Tremor often describes a condition without other neurological features whereas ORTHOSTATIC TREMOR PLUS or OT PLUS is a term which is often used to describe a condition where other neurological features also exist such as: Parkinson’s disease, Parkinsonism, Ataxia, hemifacial spasm, Restless Legs Syndrome, Tardive Dyskinesia, Essential Tremors, Head trauma, Pontine lesions, Aqueduct stenosis, Peripheral neuropathy, and others. OT PLUS has also been referred to as: SECONDARY OT, and SYMPTOMATIC OT. Pseudo-Orthostatic Tremor : dominant frequency 6.2 to 6.9 sporadic subharmonics at 8 to 18 Hz... all patients had dopamine transporter abnormalities.
*reference: 1 , 2 , 3