September is Dystonia Awareness Month. MJFF will be sharing more information on the different types and causes of dystonia, and its relationship to Parkinson's. Keep an eye on the FoxFeed blog and our social channels (#dystoniaawareness) throughout the month for more on this topic.
Dystonia -- unfamiliar to most not affected by the condition -- is a neurological disorder that causes involuntary muscle contractions. These lead to painful twisting, turning or pulling postures or movements that can interfere with normal function. Imagine, for example, that your neck was constantly pulled to the side or your toes randomly cramped under your foot.
Dystonia can involve almost any body part and can be isolated to one area or impact the entire body. It can be a distinct condition on its own -- meaning there are no other neurological symptoms -- or a component of another syndrome, such as Parkinson's disease (PD). Within Parkinson's, dystonia can be the initial sign that leads to the diagnosis, an associated symptom or related to the cycle of medication administration.
Dystonia as an Initial Symptom of PD
Most people do not demonstrate dystonia at the beginning of their Parkinson's disease, but in rare cases some will develop dystonia before any other symptoms of PD. In this context, dystonia is most often in the lower leg and it forces the foot to turn inward or the big toe to rise up on its own.
A person with dystonia as the first sign of Parkinson's may be misdiagnosed with another condition until other PD symptoms (stiffness, slowness or tremor) appear.
Dystonia as an Associated Symptom of Parkinson's
More commonly dystonia occurs with the other motor symptoms of Parkinson's and most often affects the eyes, neck and trunk.
Dystonia can cause people to blink excessively or keep their eyelids closed; this is typically associated with a sense of eye irritation and light sensitivity. The treatment of choice is botulinum toxin injections into the muscles surrounding the eyes. For those who get incomplete relief with injections or who don't want to use them, oral medications may be effective. Eye drops might soothe eye irritation, and special eyelid crutches or glasses with wire loops may help keep the eyelids up.
Dystonia can also cause a forward tilt of the neck that makes it difficult to keep the head upright. This can lead to pain in the neck, interfere with vision and walking, and make speech and swallowing problems worse. Management options include a soft cervical collar for support; physical or occupational therapy for strengthening exercises; oral medications like dopamine therapy and muscle relaxants; and, under the care of specialists, botulinum toxin injections. In select cases, spinal fusion surgery or deep brain stimulation (DBS) is offered.
The torso is another place people with Parkinson's can experience dystonia, where it can cause a person to lean forward or bend sideways and backward. Dystonia of the trunk can yield pain, shortness of breath, walking problems and falls. This symptom typically resolves upon lying down, but of course that's a temporary solution. Treatment options include physical therapy, oral medications, botulinum toxin injections, and, in some patients, spinal fusion or DBS. Canes and walkers can help to correct posture and decrease the risk of falls.
Dystonia and Levodopa
Dystonia also has a complex relationship with levodopa, the most commonly used medication to treat Parkinson's motor symptoms.
Later in their disease course, people taking levodopa may experience motor fluctuations, when the medication wears off before it's time for the next dose. Dystonia can come as part of these “off” periods. If this happens, the doctor may increase the dose or frequency of the levodopa prescription, or suggest another therapy. Extended-release formulations of carbidopa/levodopa (including Rytary and Duopa) and other drug classes (dopamine agonists, COMT-inhibitors and MAO-B inhibitors) aim to shorten or eliminate “off” periods.
Even during periods when levodopa is working well to control other symptoms such as tremor and stiffness, a person may still experience dystonia. In these cases, the doctor may recommend smaller, more frequent doses of levodopa, or try an extended-release formulation of levodopa or another drug class.
There's no one-size-fits-all medication regimen; it's a trial and error process to find what works best for every person. Each drug has potential side effects that need to be balanced against the benefits. Ultimately, if motor complications are severe and disabling and the medication adjustments are not effective, DBS may be a consideration.
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