Dystonia is a neurological movement disorder which can affect everybody at any age.
In Europe, about 500.000 people, amongst which are 45.000 children and adolescents, suffer from this disorder.
Developing in the so called movement centers in the brain, the disease has many manifestations.
Characteristic symptoms are involuntary muscle contractions which trigger abnormal postures or movements.
They can occur in the most different body areas.
Classification of dystonia
Dystonia is usually classified according to the following criteria:
Classification according to the parts of the body affected differentiates between focal, segmental, multifocal and generalized dystonia and hemi-dystonia.
Affects one single area of the body.
Affects at least two or more areas of the body that are adjacent (e.g. face and jaw, arm and neck).
Appears in two or more areas of the body that are not adjacent (e.g., face and arm; arm and leg).
Involves several body areas on both sides of the body (e.g., both legs or one leg and trunk and at least one other body region).
Affects either the left or the right side of the body.
The following forms of dystonia belong to this group:
Twisted neck - Spasmodic torticollis
Spasmodic torticollis is a technical word meaning “twisted neck”. The epithet “spasmodic" is intended to express the idea that in many cases the head is not only twisted but also that the condition can often be accompanied by hyperkinesia (nutation or trembling of the head), at least in certain movements of the head.
The disorder is characterized by slow rotation of the head about a vertical axis to one side, usually combined with slight inclination of the head, and is classified as a form of focal dystonia. In other cases there is forward or backward tilting of the entire neck. The pattern of movement is occasionally also jerky, so that in some cases there is trembling (tremor) which, depending on the pattern of movement, is called yes-yes, no-no or yes-no tremor. The muscles responsible for the movement increase in thickness (hypertrophy).
Eyelid spasm - blepharospasm
Blepharospasm comes from the Greek and means spasm of the eyelid. The main feature of the disease is arbitrary and uncontrollable winking. This winking is barely distinguishable from normal winking at the start of the condition. In time, however, it becomes spasmodic, so that ultimately the eyes can barely be kept open and genuine impairment of vision occurs. The result is severe impairment of everyday life (reading, driving, watching television).
The occupational forms of dystonia differ from other forms such as blepharospasm or spasmodic torticollis in that the involuntary muscle spasms occur only when a specific activity is performed.Writer’s cramp is a typical form of occupational dystonia: when the sufferer is not writing, his arm has no cramp. Other motor activities in which a form of dystonia specific to the activity can manifest itself are the playing of musical instruments (e.g. pianist’s cramp, guitarist’s cramp, flutist’s cramp, etc.) or some types of sport (e.g. the golfer’s “yips”, a spasm in the hand holding the club before teeing off, or in tennis).
Vocal cord spasm - Spasmodic dysphonia
(referred to in the older literature as “spastic dysphonia” or “stuttering”) is a severe vocal disorder of still largely unexplained origin. It is classed as a neurological form of dystonia and called focal dystonia of the larynx. The severity of the disease ranges from mild forms which manifest themselves as the voice “getting stuck” and thus break the flow of speech to the most severe forms which make vocal communication impossible. The consequences are not uncommonly social isolation and occupational invalidity.
Spasmodic dysphonia comes from the Greek and means a spasmodic disorder of the voice. The disease was first described in 1871 by Prof. Traube as a “spastic form of nervous trachyphonia”. Two different types of the disease were described in 1973 by Prof. Aronson. This classification is still valid today: the adductor form and the much rarer abductor form (the names refer to the muscle groups affected in each case). The adductors (from the Latin: adducere = to draw towards) are the group of muscles in the larynx which cause the vocal folds to draw together and to close the vocal folds. The abductor muscles (from the Latin: abducere = to draw or lead away) draw the vocal folds apart and allow air to pass through the windpipe (respiration).
With the adductor form, spasms over which the patient has no voluntary control occur in the inner laryngeal muscles during vocalization. The voice is very tense and groaning, and sounds strained and laborious; with more severe spasms it is characterized by the voice breaking up. In the most severe cases the voice fails completely. Accordingly, the patient has great difficulty speaking.
With the abductor form, these spasms occur with the vocal folds adbucted, i.e. opened. This gives the voice a breathy, more whispering sound.
Laughing and crying can sound normal
One peculiarity of both forms of spasmodic dysphonia is that the voice can be completely normal when laughing and crying. The voice is usually much better when singing and reciting verse, but the symptoms may be intensified under stress and in particular when on the telephone.
Spasm of the mouth, tongue and pharynx - Oromandibular dystonia
Focal dystonia of the muscles of the mouth, tongue and lower jaw is called oromandibular dystonia (OMD) (Latin oris = mouth, mandibula = lower jaw). If eyelid spasm is present in addition to dystonia of the lower half of the head, this is called Meige syndrome, which was first described in 1910 by eye specialist Henry Meige. Illustrations of this form of focal dystonia do not occur until much later, however.
Which muscles are affected?
The involuntary movements affect three different groups of muscles. The first that must be mentioned are the mimetic ones, i.e. those which control facial expressions. This is shown by the involuntary tensing of the eye, mouth and neck muscles. Patients with Meige syndrome often find the eyelid spasms more troublesome than movements around the mouth area. The second group are themandibular or masticatory muscles which are responsible for powerful biting movements and for grinding, chewing movements. OMD can, depending on the jaw movement, be subdivided into a type with jaw opening and one with jaw closure. The third muscle group contains the tongue and the pharyngeal muscles. In OMD, the tongue may constantly move in all directions. Speaking and swallowing may become completely impossible for particularly severely affected patients. Abnormal movements of the pharynx manifest themselves as a “lump in the throat” or through choking.
The involuntary movements of OMD increase under stress and emotional tension but decrease at rest and relaxation, and disappear completely during sleep. They are intensified by active movements, such as speaking.
Therapies for Dystonia
Dystonia can not (yet) be cured.
But there are different types of treatments available that can alleviate the symptoms.
This treatment drugs are injected directly into the affected muscles.
Most of the active ingredients used in the treatment of dystonia affecting neurotransmitters. They are messengers of the nervous system that transmit the instructions of the brain and thus initiate and control muscle movement.
Rhizotomy and Pallidotomy:
During surgery, certain regions of the brain destroyed or removed (pallidotomy) or nerves in the spinal cord is interrupted (rhizotomy) (these procedures are now rarely used).
Deep Brain Stimulation:
is an alternative treatment in dystonia. It is based on an implanted medical device, similar to a cardiac pacemaker. Electrical impulses stimulate precisely targeted areas of the brain.
DBS therapy relieves severe symptoms such as muscle spasms, cramps, poor posture, and involuntary movements.
When you turn on the system, it delivers a stimulation that may reduce some or all of your symptoms. When the system is turned off, your symptoms will return.
Other treatment options, such as Physiotherapy, occupational therapy and speech therapy, can only be supported concomitantly.
An accompanying psychotherapy can be useful to prevent the development of mental distress this chronic disease and to develop coping strategies.