Occupational dystonia is one form of focal dystonia where dystonic postures and movements occur while performing a specific act. The most important example is writers cramp. It is because of the habitual use of one set of muscles and their repetitive use.
The symptoms are local pain in the muscle concerned, local spasm and loss of control over the range of movements. This occurs primarily in those who do lot of writing. Person feels stiffness or tension in the hand during performing of the job of writing. It is not only the writers but the disorder may arise in any occupation involving rapid repetitive movements of short range by a small portion of the body.
Thus we may have typists, musicians, telegraphists etc who suffer from this condition. In all these occupations rapid repetitive action of small group of muscles results in fatigue. The sufferer of Occupational dystonia has difficultly in executing those tasks which he I she might be doing earlier on. The patient surprisingly may use his hand normally for shaving, eating etc.
The symptoms usually appear when the person is asked to show higher level of precision in his work. An element of psychological instability is also said to play a role. Faulty training in the use of instruments like pen etc may also be responsible.
Onset of writers cramp is gradual. As the disease progresses movements of pen become difficult and often irregular. Pen tends to slip while writing. The hand starts aching and may feel heavy and tired. Some degree of tremor may develop in the limb, As the condition worsens cramps appear more and more readily as writing is started.
Diagnosis of writers cramp is based mainly on clinical history and may have to be differentiated from a hysterical condition. The disease once develops causes distressing symptoms and interfers with the normal functioning. Some relief may be obtained by changing hand postures. Rarely the incapacity may become permanent.
Treatment of Occupational dystonia is often unsatisfactory. It consists in removal of sufferer from the type of work he/she is doing. Patient will have to temporarily suspend the work he is doing and may have to take the help of an assistant. Re education of the movements may be attempted so that hand gets some relief.
When patient feels better he may start his/her occupation in gradual manner and take periods of rest and relaxation in between the spells of work. Gradual rehabilitation is required. Besides this a light massage to the hand and limbs may be tried.
For pain resulting from Occupational dystonia, mild analgesic may be given. Prognosis in a case of writers cramps is guarded and shall be guided by factors such as early return to work and lack of discomfort while resuming the job.