This page contains information about generalised dystonia for medical professionals. For information on generalised dystonia for patients and carers please click here.
Generalised dystonia is a rare form of dystonia that most often appears in late childhood or early teens. Typically, the condition starts in a limb and then ‘generalises’ to other areas. It is a neurological movement disorder and is diagnosed and treated by neurologists specialising in movement disorders.
A dystonia is classified as "generalised"when it affects both legs and at least other body region (usually one or both arms). Generalised dystonia can either be primary where there is no identifiable cause other than genetic factors or secondary where there is an underlying cause such as another medical condition, drugs or a stroke.
Primary generalised dystonia usually appears beofre the age of 30 and is classified as early-onset. Secondary generalised dystonia can appear at any age.
Primary generalised dystonia is often caused by a mutation in the DYT1 gene. If someone inherits this mutation there is 30% chance they will develop DYT1 dystonia. If a carrier reaches the age of 30 without developing dystonia there is a good chance the dystonia never will develop.
There are a number of other genes which cause primary early-onset generalised dystonia including the DYT5 gene which causes a rare type of generalised dystonia highly responsive to treatment by dopamine called dopa-responsive dystonia.
Secondary generalised dystonia can be caused by a number of other rare conditions such as Wilson’s disease (a treatable genetic condition in which the body does not process copper properly) or neuronal brain iron accumulation syndrome (NBIA – a genetic degenerative condition in which iron is deposited in the basal ganglia).
Typically, primary generalised dystonia starts in a limb and then spreads to other areas. Involuntary spasms can occur in a foot or leg and then progress to include other limbs and the trunk. In most cases, symptoms progress and stablise within a 5-year period. Symptoms may include:
Generalised dystonia is often misdiagnosed by GPs. Conditions that generalised dystonia is mistaken for by GPs include orthopaedic problems and psychological problems. Indicators that the diagnosis might be generalised dystonia rather than these problems include:
Oral medications will generally be tried first. A trial of levodopa (usually for at least 2 months) is appropriate in all early-onset primary dystonia to identify dopa-responsive dystonia. If this is ineffective, an anti-cholinergic drug such as trihexyphenidyl can often be helpful in controlling muscle spasms and tremor. Second line treatments may include clonazepam (a strong muscle relaxant) or tetrabenazine (helps to control tremor and involuntary spasm) and baclofen (an effective muscle relaxant). A combination of medications is often advised by the neurologist. These drugs can have side effects.
Botulinum toxin injections can sometimes be helpful in reducing symptoms in some isolated areas that are affected by dystonia such as the jaw, hands, feet or leg. A surgical technique known as deep brain stimulation can provide sustained benefit in some cases. It works by inserting fine electrodes in the brain to damp down the spurious signals causing the muscle spasms. Selection of patients is done carefully with extensive testing to ensure the patient’s condition is likely to benefit from the surgery.
The degree of pain varies greatly between people with dystonia from no pain to severe pain. Pain resulting from dystonia can be in the muscles affected by spasms, or in joints where bone surfaces rub together due to twisting of posture and limbs. Sometimes, the resulting intractable pain can dominate a patient’s life and may be unresponsive to medication including that used to manage dystonia. These patients need to be referred to a pain specialist urgently to reduce the impact on health and well-being. Although the British Pain Society guidelines (2007) suggest that patients should only be referred to pain specialists when all other treatments have failed, it is now recognised that a referral should be offered when indicated by persistent pain causing distress, disability, and a negative impact on quality of life.
Adults who have genetic forms of dystonia and are considering having children may have concerns about their children developing dystonia. They may decide to seek genetic counselling to help inform their decision making. Also where parents have an infant or young child who has dystonia which may have a genetic cause, they may want to seek genetic counselling with regard to future siblings. If they choose to have genetic counselling they should seek the advice of their neurologist / paediatric neurologist and ask for a referral. There may be a wait and the counselling may not be available through the NHS except in exceptional circumstances.
For generalised dystonias, while therapeutic handling strategies can be useful, they tend not to have carryover (i.e. when the therapist releases their handling, the dystonic posture/movement tends to return). Physiotherapists usually have a wider, more supportive role including:
Last reviewed March 2012
The Dystonia Society provides the information on this page as general information only. It is not intended to provide instruction and you should not rely on this information to determine diagnosis, prognosis or a course of treatment. It should not be used in place of a professional consultation with a doctor.
The Dystonia Society is not responsible for the consequences of your decisions resulting from the use of this information, including, but not limited to, your choosing to seek or not to seek professional medical care, or from choosing or not choosing specific treatment based on the information. You should not disregard the advice of your physician or other qualified health care provider because of any information you receive from us. If you have any health care questions, please consult the relevant medical practitioner.