What is Myoclonus?
Myoclonus is the brief and sudden, involuntary jerking of a muscle or group of muscles caused by muscle contractions (positive myoclonus) or muscle relaxation (negative myoclonus) (5). These abnormal muscle movements cannot be consciously controlled. It is typically viewed as a symptom and can be related to hundreds of different underlying causes. In most cases, myoclonus is most prominent in the hands and face. In severe cases, it can create challenges for balance and stability, and limit everyday activities such as eating, talking and dressing.
How Common is Myoclonus?
Some forms of myoclonus are more common than others however it is generally not a common pathology. The prevalence of myoclonus is 8.6 per 100,000 people. After 50 years of age, the prevalence increases (2). In about a quarter of cases (27%), myoclonus is transient and usually drug induced. It affects males and females equally.
What are the Early Signs of Myoclonus?
The early signs of myoclonus will be the fast, involuntary movement of muscles. This disorder comes on very quickly and a spontaneous movement is typically a single event. Muscles can move on their own at rest, while they are being activated, or from contact with an external touch. The movements can be described as shock-like and vary in intensity. Sometimes this shaking can be severe enough to interfere with activities of daily living like eating, getting dressed, and walking (1).
What Causes Myoclonus?
Myoclonus can result from an injury or lesion in the central or peripheral nervous system pathways. This includes the peripheral nerves, brainstem, spinal cord, and cerebral cortex. Injuries to the cortex of the brain can result in regional myoclonus or entire limb myoclonus. Depending on where the movements are located and how much of the body is involved, a provider can usually localize the lesion to a specific region of the nervous system.
Myoclonus may take benign forms, such as hiccups or nocturnal myoclonus, which is an abrupt jerk that wakes you from your sleep. These are called physiologic myoclonus and occur in healthy people. Other reasons for myoclonus may be infection, traumatic brain injury, Parkinson’s disease, multiple sclerosis, epilepsy, Alzheimer’s disease, or Creutzfeldt-Jakob disease. They may also be seen in conjunction with brain tumors, kidney or liver failure, chemical or drug intoxication or other metabolic disorders. These would all be considered pathological myoclonus (6).
What is Going on in the Brain with Myoclonus?
Myoclonus is caused by a spontaneous and abrupt discharge of motor neurons to the affected muscles, usually in the cortical regions that control the muscles involved. Another structure that may be involved is the top part of the brainstem, the midbrain, which is responsible for our startle reflexes or the automatic responses we have to unexpected stimulus. Less commonly, there may also be interruption of the peripheral nerve directly innervating the muscle or muscle group involved. This can be from injuries to the regions generating the myoclonus, or to injuries to pathways that would normally shut off the spontaneous activity of the involved tissues (11).
How is Myoclonus Diagnosed?
Myoclonus can exhibit the same symptoms as many other movement disorders. It is important to take a detailed history including onset, frequency of motion, location, and speed of onset into account when diagnosing it.
Additional tests may be ordered by a physician to establish a diagnosis of myoclonus, including (6):
electromyography (EMG), which measures electrical activity from muscle directly. It commonly used to diagnose nerve and muscle dysfunction, as well as myoclonus;
Electroencephalography (EEG), which uses electrodes attached to the scalp to measure cortical brain activity that may be triggering the myoclonus jerk;
Evoked potential studies, which can capture electrical activity in the brain, brain stem and spinal cord that may be evoked by a standardized stimulus (ex. Touch, auditory or visual stimulus).
Laboratory tests, looking at urine or blood to identify possible underlying causes that are presenting similarly to myoclonus
Magnetic resonance imaging (MRI), which uses a magnetic field and computer-generated radio waves to create a 3D image of the brain, spinal cord, nerves and muscles.
How is Myoclonus Usually Treated?
Medication is the primary therapy for myoclonus is handled for patients in a typical medical setting. Most medications seek to decrease the number of spontaneous movements through inhibitory actions. As with all medications, they do have side effects and patients need to work closely with their doctor to find the correct medication and dosage (12).
Botulinum toxin injections (Botox) are also offered to control muscle activity (1,2). They offer temporary paralysis of the myoclonic muscle or muscle groups. Repetitive treatments are required, as the effects of each treatment do wear off.
Deep brain stimulation of subcortical structures, including the internal globus pallidus (part of the basal ganglia) ventral intermediate thalamic nucleus has shown some positive impacts on myoclonic symptoms (7).
How Is the NeuroRescue Program Different?
While we cannot generally cure the underlying conditions producing your myoclonus, we employ a host of advanced therapies and technologies that can help improve the function of your remaining systems. By doing so, we can often help restore your mobility, reduce your spontaneous movements, improve your balance and gait, and enhance your quality of life.
Much of what happens in myoclonus is related to hyperactivity of specific regions of the brain due to unstable neurons. The visual system is the most highly developed sensory system that we have as humans. We rely heavily on vision to track our environment, both voluntarily and reflexively. Therefore, the various types of eye movements that we generate utilize a large part of our cortical, subcortical and brainstem regions. Often the areas of hyperactivity will result in changes to eye movements being produced by those same areas (8). We find that by rehabilitating these eye movements, we can improve the function of the brain, basal ganglionic and cerebellar regions that generate them, and thus improve function in the systems that regulate myoclonic activity.
In order for you to move through and interact with the world, you first need to know where the world is. We utilize fast eye movements called saccades to take in our visual environment quickly, shifting our gaze from one object to another. This requires that saccades are fast, accurate, stable, and have very quick reaction times. As the cortical and subcortical regions are involved in saccades, all of these qualities break down with myoclonus (13). Saccades may become slow, lose accuracy, and are easy to fatigue. We find that by rehabilitating saccades in a very precise manner, we can often improve frequency and intensity of myoclonus by improving function of the specific regions of the brain that are unstable and hyperactive.
There are a host of other therapies that we engage in with our myoclonus patients. All of these have different functions and allow us to rehabilitate specific capacities. These range from visual and vestibular rehabilitation to improve stimulation to the cortical and subcortical regions, to visual optokinetic stimulation to improve motor control and postural stability (12). They include a number of different types of electrical stimulation to improve cognition, eye movements, balance, and other sensorimotor functions (9). They even include therapies such as transcranial magnetic stimulation to improve motor function and emotional regulation (4), and virtual reality exercises to improve the ability to function in the world and decrease fall risk (10).
No two myoclonus presentations are alike, and the same holds true for the NeuroRescue program. A cookie-cutter approach will be doomed to fail in a condition as complicated as myoclonus. All of our therapy protocols are driven by data from your unique diagnostic testing, with exercises and stimulation tailored to the unique needs of the individual.
How Does the NeuroRescue Program Work?
We design your unique NeuroRescue Program to be among the most comprehensive diagnostic and therapeutic protocols available today. We create individual NeuroRescue Programs based on a comprehensive analysis of every relevant neurological system and pathway, using gold-standard, cutting edge neurodiagnostic technologies and examination procedures and state-of-the-art therapies.
We begin with your Discovery Day, wherein we perform a comprehensive history of not only your condition, but your life on a timeline. This allows us to dive deeply into your case and see all of the factors that led to where you are now. It helps us uncover hidden problems and associated conditions that may be making it difficult for you to move your recovery forward.
In the case of myoclonus, this requires a deep dive into history prior to onset, family history, metabolic and inflammatory function, genetics, and other possible associated conditions.
Our examination allows us to identify the areas and pathways of your brain that have been impacted to cause your myoclonus. We begin by precisely quantifying the function of your visual, vestibular, and proprioceptive systems through computerized analysis of your eye movements, your inner ear reflexes, and your balance in a host of different sensory conditions.
We employ technologies including Videooculography and Saccadometry to measure several classes of eye movements. We use Video Head Impulse Testing to measure the function of your inner ear, and Computerized Dynamic Posturography to assess your balance in different sensory conditions.
We use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and perception of vertical in a virtual reality environment.
We combine all of this with a comprehensive physical and neurological examination of your sensory, motor, autonomic, and cognitive systems. We review any relevant laboratory testing, radiological imaging, and prior neurodiagnostic testing, and integrate that information with our findings.
We use this information to identify which parts of your brain are working properly, which systems are struggling, and the precise point at which your systems fatigue.
We can then design a NeuroRescue Program that is unique and specific to your brain, and yours alone. Your NeuroRescue Program works to rejuvenate and reintegrate the damaged neurons and pathways in your brain. It works to improve energy, endurance, and functional capacity within your fragile systems.
We use our technologies and procedures to not only see what we need to address, but also when it is time to stop and let you rest. We address your impaired neurological function from multiple angles of therapy, and provide metabolic support to improve neurological recovery.
While we cannot bring back neurons that have been lost due to this dysfunction, your NeuroRescue Program allows us to take the pathways that remain and maximize their efficiency and endurance. And by focusing on the integration of systems, we can do more than just get pathways working better, we can get them working together again. This gives us our best opportunity to help you live a healthy, vibrant, and fulfilling life.
Your Next Best Step:
Living with myoclonus is challenging. While we cannot guarantee a cure for the condition, we regularly find that most or all of the symptoms can be managed, function can be significantly enhanced, and quality can often be greatly improved.
To see if the NeuroRescue Program is right for you, contact one of our patient care coordinators to schedule your Discovery Day.
And remember, it’s never too late to start getting better.
References:
1. https://www.mayoclinic.org/diseases-conditions/myoclonus/symptoms-causes/syc-20350459
2. https://pubmed.ncbi.nlm.nih.gov/24037428/
3. https://www.ncbi.nlm.nih.gov/books/NBK537015/
4. https://www.frontiersin.org/articles/10.3389/fnhum.2020.00292/full
6. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Myoclonus-Fact-Sheet
7. https://pubmed.ncbi.nlm.nih.gov/20623686/
8. https://www.sciencedirect.com/science/article/pii/S2590112519300155
9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5766640/
10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5890210/
11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5575623/
