Download FND app Android Aapp IoS App
FND Links Feedback Donate Language
  • English
Home / Symptoms / FND Symptoms / Functional Movement Disorders

Functional Movement Disorders

Functional Tremor/ Dystonia / Walking Problems and Other Functional Movement Disorders

What are Functional Movement Disorders?

A functional movement disorder means that there is abnormal movement or positioning of part of the body due to the nervous system not working properly (but not due to an underlying neurological disease).

You can read about each of these symptoms in more detail on their own page (Functional Tremor, Functional Dystonia/Spasms, Functional Jerks/Myoclonus, Functional Gait Disorder), some people just have one type of movement disorder. Some have several.

Functional Tremor is the commonest type of Functional Disorder

Patients with fixed dystonia often have a clenched hand (below) or an ankle that has twisted in (inverted ankle) – Video

Patients with a functional movement disorder may experience a range of distressing and disabling symptoms:

Tremor – When an arm or leg shakes uncontrollably. In functional tremor this is often quite variable. It may even disappear when you are distracted but at other times be very disabling.

Jerks / Twitches – Some people experience jerky types of movements. This may be particularly in response to loud noises, certain kinds of lighting or bursts of pain

Spasm / Contractures / Dystonia – Some people find that their hands or feet develop abnormal postures which are hard to overcome. This may be a temporary intermittent problem (a spasm) or may be more chronic (this is usually called fixed / functional dystonia or contracture). Patients with functional dystonia often have a ‘clenched hand’ or a twisted foot (See opposite)

Gait problems – A variety of gait (walking) problems can occur as part of a functional illness. Most common is the ‘dragging’ gait seen in patients with functional weakness of one leg. Other types of gait include a generally unsteady gait, often associated with a history of previous falls and a heightened fear of future falls.

Unlike other movement disorders (e.g., Parkinson’s disease), a functional movement disorder is not caused by damage or disease of the nervous system. It is however due to a reversible problem in the way that the nervous system is working.

This means that a functional movement disorder can get better and even go away completely.

How is the diagnosis made?

The diagnosis of a functional movement disorder is usually made by a neurologist. It can be a particularly difficult diagnosis to make because it requires expert knowledge of the full range of movement disorders due to neurological disease, many of which are unusual or even bizarre.

It is therefore difficult to summarise all of the clinical features of functional movement disorders. They often occur in relation to injury and the onset can be sudden. The following are some examples

Tremor (shaking) – typically a functional tremor is characterised by:

  1. Tremor that disappears transiently or changes in rhythm when copying movements with the good arm or leg. This is called the “entrainment test”
  2. Difficulty making rhythmical movements with your good hand (or leg)
  3. Times when the tremor is absent
  4. Variable frequency (varying speed of how “fast” the shake is)
  5. Tremor that gets a lot worse when someone tries to hold your arm or leg still

Jerks – this is called myoclonus. Functional myoclonus is characterised by

  1. Jerks in anticipation or response to loud sounds or noise (although there are other causes of this)
  2. Presence of a special brainwave called “Bereitschaftpotential” which is not usually present in patients with myoclonus cause by neurological disease

Benign Twitches – these are sometimes called ‘benign fasciculations’. Most people have small twitches from time to time, especially around the eye, in the fingers and in the calves. Such twitching is so common that to experience it occasionally is normal. However, some people find that they experience more and more of this muscle twitching until it is present in multiple areas of their body, for most of the time. This can lead to understandable anxiety about what is causing the symptoms, which in turn makes the twitching even worse. Generalised benign twitching like this is known to occur more frequently in medical students and doctors who, on developing these symptoms, worry that they might have motor neurone disease (known in the USA as ALS). In fact the twitching seen in this condition, which affects the whole muscle fibre, is different to the smaller wriggling movements, called fasciculations, seen in motor neurone disease. The condition is therefore somewhat misnamed as benign fasciculation. There are other causes of generalised muscle twitching but benign fasciculation remains the most common clinically.

Spasms  – Functional spasms are called ‘dystonia’. They often occur in the hand and wrists. The hand may go in to something called ‘carpopedal spasm’. (see picture). This does occur with other medical conditions too such as having a low blood calcium and your doctor should consider these before deciding they are ‘functional’. Carpopedal spasm is especially likely to occur during hyperventilation (click here to find out more).

Fixed posture (functional dystonia) – This describes a position, usually of the hand or feet which remains fixed for all or most of the time. Fixed postures like this are usually associated with some functional weakness of the limb and commonly associated with pain. There is an overlap here with a condition called Complex Regional Pain type 1 . The two most common types are:

  1. In the hand (where the appearances can be similar to carpopedal spasm or sometimes with a hand that is “clenched”)
  2. In the foot where the ankle typically turns inwards.

Functional Gait Disorder – There are various types of functional gait disorder. describes difficulty walking (an abnormal gait) which is not due to an underlying neurological disease. Different types have been described including:

  1. Excessive slowness – a very slow walk with the feet having a tendency to stick to the ground.
  2. ‘Walking on ice’ pattern – a cautious gait with the feet far apart and the legs quiet stiff.
  3. Crouching. A gait where the person looks as if they are crouching. Often this is associated with a fear of falling
  4. Sudden knee buckling. Typically this is associated with a finding of functional weakness in the legs. Sometimes this problem is called ‘drop attacks’, although it is important to recognise that there may be other causes of this such as knee problems.
  5. Unsteady. A generally unsteady gait with sudden sidesteps.

How do functional movement disorders happen?

Functional movement disorders arise for different reasons in different people. Some of the apparent precipitating factors are similar to those described for functional limb weakness especially:

After an injury / with pain—A high proportion of patients with functional dystonia (and to a lesser extent tremor) have a physical injury or a painful limb at the time of onset. There is an overlap here with a condition called Complex Regional Pain  . The movement disorders seen in this condition (especially the dystonias) are indistinguishable from those described as functional movement disorders. Functional jerks and tremors also occur in patients with chronic pain syndromes such as back pain and neck pain.

prunes juice weight loss yellow jacket diet pills weight loss in dog burn weight loss pill marie osmond weight loss to lose weight in spanish weight loss supplement stack my weight loss story does low dose naltrexone cause weight loss moringa weight loss how to use hydr xycut to lose weight does yoga help you lose weight diet pepsi keto keto diet hungry dr nking on keto diet is it safe to do keto diet beginners guide to keto diet fasting diet pills lean green diet pills ez weight loss pills how many calories should you eat on a keto diet slender curves diet pills diet pills that expand in your stomach shane dawson weight loss cost of keto diet shark tank weight loss pill episode rapid diet pills weight loss shirt

home window replacement in east northport ny wooden door repair kit replacement windows cheap anderson windows replacement sashes all wood replacement windows average cost of replacement vinyl windows cost to replace rotted window sill easton vinyl replacement windows reinstall windows after hard drive replacement viking replacement windows full frame replacement window installation home window replacement price utah window replacement santa cruz ply gem window sash replacement screen window repair home window repair phoenix az cheap power window repair home window repair pittsburgh 15237 window repair fargo nd window repair person 24 hour window repair near me conservation area windows replacement house window replacement jacksonville window repair apple valley ca replacement window cincinnati replacement window installers near me replacement windows huntsville house window replacement salt lake city

thc oil cerebral palsy and cbd oil doses is cannabis oil legal in georgia what van i mix cbd oil with to drink cbd oil for ulcerative colitis dosage cbd oil pueblo co hemplucid full spectrum cbd oil cbd oil for anxiety story naples fl cbd oil naturopathica cbd oil where to buy cbd oil south dakota robyn cbd oil cbd oil 60 count lollipops brain cancer cannabis oil does cbd oil interact with alcohol how to make cannabis oil cbd oil nerve pain foot hemp seed growth conditions for cbd oil peppermint flavored cbd oil cbd oil botanical name where is cbd oil not legal is organic cbd oil legal in all 50 states cbd oil ponce city market 3rd party tested cbd oil feds raid health food store over cbd oil what will cbd oil do to me ananda professional cbd oil 600thc frer ben carson cbd oil

best male enhancement 2021 male libido xl really work do male libido pills work how long does a viagra pill last pills for testosterone how to tell if a man is taking viagra as seen on tv male enhancement pills top supplements viagra types cialis vs viagra effectiveness does phgh male enhancement work does walgreens sell testosterone pills maxsize male enhancement formula cream why men need viagra increase testosterone homeopathy best rated sex pill search by name free viagra samples no shipping testosterone supplements heart attack how to get a longer penis without pills vigorous male enhancement pills herbal remedies for sexuality viagr male enhancement pills male enhancement pill that is a white capsule penis enlargement and stamina pills best price viagra hoe long tske for penis pills to work what is the generic for cialis