Parkinson’s disease is a progressive neurological disorder with a wide range of motor symptoms including slowness of movement,  muscle rigidity, and dystonia, as well as non-motor symptoms.

What is dystonia?

Dystonia, or abnormal muscle tone, is characterized by involuntary repetitive twisting and sustained muscle contractions, which result in abnormal movements and postures. The symptoms usually begin in one body region, such as the neck, face, vocal cords, arm, or leg, and then may spread to other parts of the body.

While dystonia can be a result of an inherited condition caused by genetic mutations (primary dystonia), it also can result from exposure to certain drugs, birth injuries, strokes, or as a symptom of other neurological disorders, such as Parkinson’s disease. In such cases it is known as non-primary or secondary dystonia).

Dystonia unrelated to treatment can be typical (abnormal contraction or twitch of the eyelid, a crick in the neck), atypical (parkinsonian writer’s cramp, involuntary forward flexion of the spine, failure of the normal relaxation of pelvic floor muscles), or occurring in early-onset Parkinson disease (the so-called kinesigenic foot dystonia, considered a hallmark of Parkinson’s disease).

Causes of dystonia in PD

In some instances, secondary dystonia may arise as a result of treatment with levodopa in Parkinson’s disease patients. Levodopa is a chemical that is converted into dopamine, a chemical messenger in the brain. It is a shortage of dopamine that causes Parkinson’s disease and dopamine itself is thought to play a role in dystonia, although the exact nature of that role has not been clarified.

Dystonia can be caused both when the effect of Levodopa is too strong and too weak. Off-period dystonia, which occurs when the effect of Levodopa is wearing off, causes symptoms such as postural changes in the hands, feet and neck, while on-period dystonia happens when levodopa is at its most effective.

Pain from dystonia may be the most severe pain experienced by people with Parkinson’s disease. Both pain and cramped postures affect a patient’s quality of life. The Parkinson’s Disease Foundation (PDF) advises patients to work with their doctor to find the best treatment to manage dystonia. It also can help to connect with others who are living with Parkinson’s disease and dystonia through support groups, online groups, and organizations like the PDF.

Note: Parkinson’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.