What is dystonia?
Among the movement disorders - known as dyskinesias - dystonia stands out, responsible for involuntary muscular contractions and spasms that force the subject to take abnormal physical postures or to carry out unusual, often painful movements. A dystonic patient is unable to assume a natural position again or, otherwise, he would be able to modify the unusual position but gradually, using an abnormal effort and a sometimes exaggerated and vain physical suffering.
Involuntary muscle contractions force the body to perform repetitive movements and uncomfortable and twisted postures; there are about 13 dystonic forms, sometimes typical of some serious pathological forms. Unfortunately, for most dystonias, there is no definitive cure; however, improvements can be achieved through the administration of specific pharmacological specialties, which we will analyze in the course of the discussion.
Currently, it is estimated that in the USA 300, 000 people are affected by dystonia, while in Italy 20, 000 dystonic patients have been registered. More generally, dystonia occurs in 370 subjects per million healthy individuals.
The disease can affect indiscriminately men, women and children of all ages and of all races; however, some studies have found minimal female prevalence in some forms of dystonia, while in humans it is believed that the legs and arms are the sites most affected by the disorder, although every anatomical area of the body is considered to be a potential target of the disorder .
Dystonia is one of the most common movement disorders, after Parkinson's disease and tremor.
Dystonia is a chronic disease and only rarely does it affect the patient's cognition of the patient; it is also unlikely that dystonia is directly related to a decrease in an individual's life expectancy. However, it is important to remember that dystonia, when manifested as a symptom of another pathology, could still generate short or long term complications.
Dystonia does not identify terminal pathologies; sometimes, however, involuntary muscle movements occur with an intensity and frequency such as to invalidate the affected patient, and to seriously compromise his quality of life. Based on the form of dystonia, the disease can generate different degrees of pain and disability, characteristics classified on an ideal scale of evaluation (pain / disability: zero - mild - medium - severe). Muscle contractions are protracted over time and are responsible for abnormal postures and repetitive, uncontrolled torsion movements; for some authors, the torsion of movements generated by dystonia is comparable to the movement of the snake [taken from www.distonia.it]
However, despite the multiple and heterogeneous forms of dystonia - in which patients express movements, postures and difficulties of different magnitudes - there are two conductor elements, which unite all the dystonic forms: the frequency and the cadenced repetition of the anomalous contractions Involuntary muscles are diagnosed in any type of dystonia [from www.dystonia-foundation.org].
In some patients, the classic form of dystonia is also accompanied by extravagant movements within a specific context. An example is given to understand the concept: during a simple action, such as writing, the patient suffering from dystonia could present additional bizarre atypical movements. This is a dystonia of action, in which dystonic movements are worsened by the putting into practice of voluntary movements: the action dystonia appears just in conjunction with the execution of a wanted gesture, although this is simple (eg writing) .
Age of onset
The "age of onset" of dystonia refers to the age of the patient in which the first dystonic symptoms begin. Depending on the age, two first forms of dystonic disease can be distinguished, each of which will be further subdivided according to the general characteristics:
- Early-onset dystonia (infantile-adolescent): the first alterations of muscular movement arise at an early age, during childhood or adolescence. The infantile forms of dystonia are rather rare; however, most of the time they appear at 9 years of age and mainly involve a limb.
- Late-onset dystonia: dystonia appears after the age of 30, particularly between 40 and 60 years. Late-onset forms of dystonia are the most common.