Oromandibular dystonia
| Classification according to ICD-10 | |
|---|---|
| G24.4 | Idiopathic orofacial dystonia |
| ICD-10 online (WHO version 2019) | |
The oromandibular dystonia ( Orofacial dystonia , lat. Os "mouth"; mandibula "lower jaw (bone)"; facies "face"; gr. Dys "bad," "wrong"; lat. Tonus "voltage") is a neurological disorder, in which there is persistent, tonic cramping of the muscles of the lower half of the face or the lower jaw. The affected muscles become involuntarily tense, which can make it difficult to speak and eat. In addition, there is often pain. It belongs to the group of dystonia .
Epidemiology
Careful estimates assume a prevalence of 2 / 100,000 inhabitants for oromandibular dystonia . When combined with spasms of the facial muscles of the upper half of the face ( Meige syndrome ), the prevalence is around 7 / 100,000.
etiology
The majority of oromandibular dystonias are considered " idiopathic, " so the cause is unknown. In addition, however, tardive dystonias (late effects of therapy with neuroleptics ) play an important role. If the dystonia occurs in children or adolescents, a symptomatic cause and a later spread to other parts of the body must be expected. Structural changes in the area of the basal ganglia or the brain stem have been demonstrated in individual cases . Genetic predisposition also plays a role.
Appearance
The main result is persistent tension in the muscles of the mouth, chin and floor of the mouth. While dystonias of the facial muscles mostly affect socially or cosmetically, dystonias of the masticatory muscles can lead to hindrance when eating and speaking as well as considerable tooth wear.
Some patients can temporarily release the spasms with certain movements or maneuvers (e.g. holding a finger against it) ( gesture antagonistique ). Pain in the cramped muscles is particularly common when the masticatory muscles are involved.
therapy
Treatment with botulinum toxin A is the method of choice today. Treatment of the facial muscles is easiest, while that of the muscles that close the jaw is somewhat more complicated. The treatment of oromandibular dystonia of the jaw opening type remains problematic. Placing the injection in the muscle covered by the lower jaw bone ( lateral pterygoid muscle ) is complicated and the effect is often unsatisfactory due to the involvement of muscles in the floor of the mouth and neck.
L-Dopa as well as Trihexyphenidyl , Baclofen , Neuroleptics and Tetrabenazine are available for further drug therapies . However, the effects of these substances are often unsatisfactory and, for the most part, are not approved for the indication ( off-label use ).
Finally, surgical cutting of the corresponding nerve is available as a surgical procedure. If the indication is carefully identified and the symptoms are appropriate, the effect can be excellent, but the effect is on the one hand associated with a surgical procedure and on the other hand irreversible. In particularly handicapped cases, deep brain stimulation can finally be considered, but this is only possible in specialized centers.
In individual cases physiotherapy and electrical stimulation ( TENS ) have been described as helpful. Massages, neck ties, splints, etc. usually lead to a worsening of the dystonia. Learning about relaxation techniques can be particularly helpful if the dystonia increases significantly under psychological tension .
literature
- Conrad, Ceballos-Baumann: Movement disorders in neurology. ISBN 3-13-102391-0 .
- Poeck, Hacke: Neurology. 10th edition, Berlin / Heidelberg 1998
