What Is A Movement Disorder?
Movement Disorders
Movement disorders can be some of the most frustrating and difficult problems anyone faces. People living with them can feel like they’re losing control of their bodies, struggling to make the movements they want, and finding it harder to take part in the world around them.
In the broadest sense, movement disorders fall into two groups. In hyperkinetic disorders, people move too much, with unwanted or intrusive movements. In hypokinetic disorders, people move too little, with slow movement and trouble starting movements. Some conditions, such as Parkinson’s disease, include both, such as tremor along with slowed movement.
Many people describe living with a movement disorder as a struggle for control of the body. Some say they feel like a marionette, as if someone else is pulling the strings. They try to move a muscle and nothing happens, or a different muscle moves instead.
Movement disorders can cause muscle spasms or contractions that lead to involuntary postures, along with changes in walking and balance. They can be uncomfortable or even very painful. Tremor can make handwriting hard to read and make it difficult to hold utensils to eat. Falls are a common and serious concern.
What Are Some Types of Movement Disorders?
Tremor. Tremors are among the most common movement disorders. The most common is essential tremor, which causes unwanted rhythmic shaking, usually of the hands and sometimes the head. Essential tremor usually eases when the body part is at rest and gets worse with movement.
Dystonia. Dystonia causes involuntary muscle contractions that pull a body part into abnormal, often twisting postures. Some forms hold the body part in a fixed position, others involve repetitive movements, and some people have both. Dystonia can also be very uncomfortable because of the constant muscle contraction.
Myoclonus. Myoclonus causes sudden, shock-like jerks of a muscle or group of muscles, driven by sudden bursts of electrical activity in parts of the movement system.
Neurodegenerative conditions. Parkinson’s disease is the most common neurodegenerative condition that causes a movement disorder, with tremor, slow movement, balance problems and falls. Progressive supranuclear palsy and multiple system atrophy are other neurodegenerative conditions that cause movement problems.
Many people have more than one type of movement disorder at the same time. Symptoms may come and go or be constant, and either way they can be very frustrating to live with.
How Common Are Movement Disorders?
Essential tremor is the most common movement disorder in adults. About 1% of the population has essential tremor, and it becomes much more common with age. About 4.6% of people 65 and older have essential tremor, rising to nearly 22% of people 95 and older (1).
Primary dystonia is less common, affecting between 2 and 50 people per million for early-onset dystonia and between 30 and 7,320 per million for late-onset dystonia (2).
Myoclonus affects about 8.6 people per 100,000 (3). Parkinson’s disease is much more common, with about 1.1 million people in the United States living with it (4).
What Causes Movement Disorders?
Movement disorders can involve several parts of the brain, including the basal ganglia, the cerebellum, the frontal motor cortex and the parietal sensory cortex, in various combinations. Most arise from problems in the basal ganglia, the cerebellum or both (5).
Many movement disorders appear to involve a genetic tendency combined with other factors, such as injury or neurodegeneration, that bring the disorder out (6).
What Goes Wrong in the Brain With Movement Disorders?
In a simplified view, the basal ganglia contain two major pathways, often called the direct and indirect pathways. The direct pathway helps start movement and acts like a gas pedal. The indirect pathway helps stop movement and acts like a brake. Normal movement depends on the right balance between the two. We need to press the gas to start a movement, then ease off and press the brake when it’s time to stop.
Many movement disorders involve a loss of this balance. In hypokinetic disorders like early Parkinson’s disease, it’s as if the brain can’t take its foot off the brake and press the gas. In hyperkinetic disorders like dystonia, it’s as if the gas pedal is pressed too hard and the brakes don’t work well (7).
Problems with how the brain combines its sensory maps may also play a role in some movement disorders. The brain builds automatic maps from the eyes, the inner ear and the muscles and joints to keep track of where the body and its parts are in space and in relation to gravity.
The parietal lobe holds a map of the body in the sensory cortex, where you feel most physical sensations. In some movement disorders, problems in the basal ganglia can blur this map, so the brain’s sense of where one body part ends and another begins becomes less precise. This can make it harder to control individual muscles (8).
In other conditions, one theory is that the brain senses a mismatch between signals from the eyes and the inner ear, creating a false sense of where the body is in relation to gravity. Some postures and muscle contractions may then develop as the brain’s attempt to resist a fall that isn’t actually happening (9).
In still other cases, timing systems in the brainstem that help coordinate movement can break down, or cerebellar systems that process feedback from the muscles and joints can degenerate. One theory is that the brain then turns up the volume on that feedback to keep track of the body, which may contribute to tremor (10).
How Are Movement Disorders Usually Treated?
Treatment depends on the specific disorder. Common options include medications, such as dopamine replacement for Parkinson’s disease, and botulinum toxin (Botox) injections for dystonia (11). These treatments can be very helpful in managing symptoms, though they don’t stop the underlying disease from progressing. Deep brain stimulation can help some people when other treatments aren’t enough, but it involves brain surgery and its risks. Physical, occupational and speech therapy are also important parts of care.
How the NeuroRescue Program Can Help
We don’t aim to cure movement disorders. Some are caused by neurodegenerative diseases, such as Parkinson’s disease, which have no known cure. For every patient, our focus is on improving function and quality of life, not curing disease. Our care works alongside your neurologist and other providers, never in place of them. Please don’t change any medication without talking with your prescriber.
The therapies in your NeuroRescue Program are chosen based on your history, symptoms and test results, and tailored to your individual needs.
Eye movements and balance. Much of the difficulty in movement disorders involves knowing where you are in space. Your brain combines signals from your muscles and joints, your inner ear and your eyes to build a picture of where you are. Your eyes constantly scan your surroundings using saccades, quick jumps from one point to another.
To move safely through the world, saccades need to be fast, accurate and quick to start. The basal ganglia, which are central to many movement disorders, also help generate saccades, so saccades often become slow to start, less accurate and quick to tire.
Research has linked saccade problems in Parkinson’s disease to poor balance (12), difficulty turning (13) and freezing while walking (14). Saccade problems have also been found in cervical dystonia (15), essential tremor (16), ataxia (17) and myoclonus (18). We use targeted saccade exercises with the goal of supporting balance, walking and stability and reducing unwanted movements.
Anti-saccades are a more complex type of eye movement, in which a person must hold back the urge to look at a new target and look the other way instead. Anti-saccades draw on the brain’s planning and self-control systems. Research shows that anti-saccades are affected in Parkinson’s disease, and these changes have been linked to problems with planning, reasoning and emotional control (19). We use anti-saccade exercises with the goal of supporting flexible thinking and emotional regulation.
Other therapies. Depending on your needs, your program may include eye exercises to engage specific brain and cerebellar regions (20); complex movement tasks to help the cerebellum and frontal lobes work together (21); vestibular rehabilitation, which has been studied for balance, walking and thinking (22); optokinetic visual stimulation, which has been studied for movement control and posture (23, 24); various forms of electrical stimulation, applied through the skin, which have been studied for eye movements, balance, walking, tremor, blood pressure regulation and swallowing (25, 26, 27); and virtual reality exercises, which have been studied for improving daily function and reducing fall risk (28).
Transcranial magnetic stimulation. TMS has been studied for improving movement, balance and mood in movement disorders (29). At our clinic, TMS is provided by our psychiatric mental health nurse practitioner, who will evaluate whether it’s appropriate for you.
Knowing when to stop. It’s one thing to know what to do, and another to know when to stop. Even the right therapy can backfire if fragile brain systems are pushed past their limits. We pay close attention to how quickly your systems tire, so we can pace your therapy to keep you moving forward and avoid setbacks. At the end of your program, we give you exercises to continue at home to help maintain your progress.
How the NeuroRescue Program Works
Your NeuroRescue Program begins with your Discovery Day. We start with a detailed history of your condition and your life on a timeline. This helps us understand the factors that may have contributed to where you are now, and identify related conditions that may be making it harder to move forward.
We measure how your visual, vestibular and balance systems are working through computerized analysis of your eye movements, inner ear reflexes and balance under different conditions. Our testing includes videonystagmography and saccadometry to measure several types of eye movements, the video head impulse test to measure inner ear reflexes, and CAPS computerized posturography to assess your balance under different sensory conditions. We also use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and your perception of vertical in a virtual reality environment.
We combine this with a thorough physical and neurological exam of your sensory, motor, autonomic and cognitive systems. We also review any relevant lab work, imaging and prior testing, and integrate it with our findings.
Together, this helps us understand which parts of your nervous system are working well, which are struggling, and how quickly they tire. We use that information to design your personal NeuroRescue Program, aimed at improving function and endurance in the systems that need support.
We can’t bring back nerve cells that have been lost. What we can do is work with the pathways that remain, helping them work more efficiently and work better together. Our goal is to help you move with more control and confidence and stay active in the parts of life that matter most to you.
Your Next Step
Living with a movement disorder is challenging, but many symptoms can be managed, and function and quality of life can often improve. To find out if the NeuroRescue Program is right for you, contact one of our patient care coordinators to schedule your Discovery Day.
It’s never too late to take the next step.
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