Myoclonus-dystonia is a movement disorder that combines sudden, lightning-like muscle jerks (myoclonus) with dystonia, most often in the neck, shoulders, arms and trunk. It usually begins in childhood or adolescence, and in many families it is caused by a change in the SGCE gene, a form known as DYT11 or DYT-SGCE. The jerks typically get worse with movement, stress or concentration, and the dystonia often takes the form of cervical dystonia or writer’s cramp.
Deep brain stimulation is one of the most effective treatments when myoclonus-dystonia is disabling, and the jerks in particular usually respond very well. In our own case series, patients treated with DBS for cervical dystonia, Meige syndrome and myoclonus-dystonia have shown more than 90% improvement in their symptoms, based on clinical assessment and documented on video. Individual results vary. The video on this page shows one of our patients before and after surgery.
Before and after DBS: our myoclonus-dystonia patient
This is our patient with myoclonus-dystonia before and after deep brain stimulation with Prof. Atilla YILMAZ, MD. The patient gave written consent for the video to be published. Results vary from patient to patient.
Symptoms of myoclonus-dystonia
- Myoclonus: brief, shock-like jerks, mainly of the neck, shoulders, arms and upper trunk. They can make writing, eating, drinking from a cup or carrying objects very difficult.
- Dystonia: most often cervical dystonia (head turning or tilting) or writer’s cramp; it can be mild or the main problem.
- Triggers: movement, holding a posture, stress, excitement and concentration make the jerks worse.
- Alcohol sensitivity: many patients notice that a small amount of alcohol briefly reduces the jerks. This is a typical clue for doctors, but alcohol is not a treatment and carries a real risk of dependence.
- Psychological symptoms: anxiety, panic, obsessive-compulsive symptoms and depression are more common in myoclonus-dystonia than in the general population and deserve attention as part of care.
What causes myoclonus-dystonia?
The best-known cause is a change in the SGCE gene (DYT11). It is inherited in an autosomal dominant way, but because of a mechanism called maternal imprinting, symptoms usually appear only when the gene change is inherited from the father. Some patients have no SGCE change; other genes or no identified cause may be found. Genetic testing helps confirm the diagnosis and counsel the family. See genetic dystonia and DBS.
How is myoclonus-dystonia diagnosed?
The diagnosis is clinical, supported by the typical age of onset, the distribution of the jerks, a family history and genetic testing. A neurologist will exclude other causes of myoclonus. Brain MRI is usually normal.
How is myoclonus-dystonia treated?
- Oral medications can reduce jerks in some patients, but side effects often limit them. Choice and dosing belong to your neurologist.
- Botulinum toxin can help a focal dystonic component, such as cervical dystonia.
- Deep brain stimulation is used when the jerks or dystonia remain disabling. It treats both components at once.
DBS for myoclonus-dystonia
The globus pallidus internus (GPi) is the most commonly used target; it improves both the myoclonus and the dystonia. The thalamus (ventral intermediate nucleus) has been used in some centers when the jerks dominate. Electrodes are placed on both sides under general anesthesia, as described on DBS surgery and recovery. Full details: treatment for myoclonus-dystonia.
In the published literature, SGCE myoclonus-dystonia is one of the genetic dystonias that responds well to pallidal DBS; in this group a younger age at onset was associated with a smaller benefit.[1] In our own center: In our own case series, patients treated with DBS for cervical dystonia, Meige syndrome and myoclonus-dystonia have shown more than 90% improvement in their symptoms, based on clinical assessment and documented on video. Individual results vary.
How quickly does it work?
The jerks often settle within days to weeks after stimulation is started. Dystonic postures improve more gradually, over months, while the settings are adjusted in person or remotely.
Frequently asked questions
What is the difference between myoclonus-dystonia and myoclonic dystonia?
They are two names for the same condition: dystonia combined with quick, shock-like jerks (myoclonus). The genetic form caused by SGCE is also called DYT11.
Is myoclonus-dystonia hereditary?
Often yes. SGCE myoclonus-dystonia is inherited, and symptoms usually appear when the gene change comes from the father. A genetic counsellor can explain the risk for your family.
Does DBS work for myoclonus-dystonia?
Yes. Pallidal DBS usually improves the jerks very well and the dystonia too.[1] In our own case series, patients treated with DBS for cervical dystonia, Meige syndrome and myoclonus-dystonia have shown more than 90% improvement in their symptoms, based on clinical assessment and documented on video. Individual results vary.
Which DBS target is used for myoclonus-dystonia?
Most often the globus pallidus internus (GPi), which treats both jerks and dystonia. The thalamus is an alternative in selected patients whose jerks dominate.
Can children with myoclonus-dystonia have DBS?
Myoclonus-dystonia often starts in childhood. Whether DBS is right for a child is decided case by case after a full evaluation.
Sources
- Artusi CA, Dwivedi A, Romagnolo A, et al. Differential response to pallidal deep brain stimulation among monogenic dystonias: systematic review and meta-analysis. J Neurol Neurosurg Psychiatry. 2020;91(4):426–433. Source