Movement disorders are a group of nervous system (neurological) conditions that either result in increased movements (such spasm, jerking, or shaking) or decreased or slowed movements. They may have an impact on voluntary movements or provoke involuntary, out-of-control motions.
There are various types of movement disorders that vary in their severity and scope. While certain conditions can impact the entire body, others may only affect a specific part. Some movement disorders can hinder individuals from carrying out certain tasks such as writing, while others can make it challenging to walk and perform daily movements.
Movement disorders primarily come in different forms:
- Hyperkinetic movement: Increased movement is a feature of hyperkinetic movement disorders. Hyper is short for “over” or “beyond,” while kinetic is short for “movement.” It may have an impact on voluntary movements or result in involuntary actions that are beyond the control.
- Akathisia: As a result of internal restlessness, akathisia makes it difficult to sit still or hold still. Use of specific medicine classes, particularly antipsychotic (neuroleptic) drugs, is linked to akathisia.
- Ataxia: This movement disorders has an impact on the region of the brain that regulates coordinated movement. Ataxia can result in the lack of coordination or clumsiness in maintaining balance, speech, and movements of the limbs, among other symptoms. Ataxia can be brought on by a wide range of conditions, including hereditary and degenerative illnesses. An infection or another illness that may be treated can also induce ataxia.
- Chorea: Chorea is a movement disorder characterized by rapid, irregular, and involuntary movements. These movements tend to be short in duration, repetitive, and unpredictable. Typically, the limbs, trunk, face, and mouth are involved. Excessive fidgeting is a common symptom of chorea, giving the impression that the patient is constantly dancing, restless, or unable to keep still. Huntington’s disease often leads to the development of chorea. Another related movement disorder, athetosis, is characterized by a continuous flow of slow, twisting, or writhing movements, frequently affecting the hands and feet. In contrast, ballism involves more forceful and exaggerated movements, such as sudden and vigorous throwing of the arms or legs.
- Dystonia: This abnormal movement causes twisted, repeated movements and long-lasting involuntary muscle contractions. One body part or the entire body may be affected by dystonia. A common symptom of cerebral palsy and a number of neurodegenerative diseases is dystonia.
- Myoclonus: An uncontrollable muscle jerk or twitch known as myoclonus occurs briefly. Muscles that suddenly tighten or relax (positive myoclonus or negative myoclonus) are a common symptom in those who have myoclonic jerks or twitches.
- Spasticity: When a patient tries to move or even when they are at rest, specific muscles suddenly contract due to a disruption in their normal muscular movement patterns. Movement is hindered, and it may also have an impact on speech and gait.
- Stereotypies: Stereotypies are complicated and typically involve motions on both sides of the body. They are patterned and have a consistent appearance. Rocking, flapping hands, pacing, and clenching of the body are some examples. Stereotypes may be present in a variety of disorders, such as Rett syndrome and autism spectrum disorder.
- Tremor: The hands, head, or other body parts shake rhythmically as a result of this movement disorder. One or more parts of the body may be moving. The muscles repeatedly contract and relax, which causes tremors. Essential tremor is the most common type.
- Tics: Tics are motions that are patterned, repetitive, and nonrhythmic. Simple tics are brief and only involve a few muscles. Examples include blinking, scrunching of the face, head jerking, clearing of the throat, and grunting. Tics that require more muscles and linger longer are called complex tics. Examples include uttering specific words or phrases and hopping. Tourette’s syndrome is associated with tics, though other illnesses can also cause them.
- Hypokinetic movement: Slow or reduced movement is a symptom of hypokinetic movement disorders. “Hypo” is Greek for “beneath” or “below.” It typically has an impact on voluntary movement.
- Parkinsonism: Parkinsonism represents the primary form of hypokinetic movement disorder. It is an umbrella term used to describe brain disorders that result in slowed movement, rigidity (stiffness), tremor, or balance issues.
There are numerous causes. The most frequent causes include Parkinson’s disease and a few drugs that block dopamine. Degenerative conditions including progressive supranuclear palsy and multiple system atrophy are other causes. Parkinsonism may also result from a stroke or recurrent head trauma.
- Bradykinesia: Bradykinesia is a type of hypokinetic movement. It manifests as reduced speed of movement and gradual hesitations or pauses during the execution of ongoing movements. Bradykinesia is considered one of the key symptoms of Parkinson’s disease.
- Types of movement disorders:
- Essential tremors: The uncontrollable shaking of the body is caused by an essential tremor. It typically impacts the hands and arms, but it can also impact other body parts like the head, the voice, and others.
- Huntington’s disease: Huntington’s disease, an inherited and progressive disorder, can be diagnosed through genetic testing. It encompasses three main components: uncontrolled movements, cognitive impairment, and psychiatric manifestations.
- Parkinson’s disease: Tremor, muscle stiffness, slowed or decreased movement, or imbalance are symptoms of this slowly progressing condition. Additionally, it may result in symptoms that are unrelated to movement, such as a loss of smell, constipation, acting out dreams, and cognitive decline.
- Multiple system atrophy (MSA): MSA is a rare condition characterized by the degeneration of specific areas in the brain. It could result in ataxia and parkinsonism.
- Periodic limb movement disorder (PLMDP): PLMD involves recurrent limb movements that happen when sleeping and may keep the patient from falling asleep. The big toe extends and the ankle, knee, and hip flex as part of the lower extremities’ typical limb movements.
- Progressive supranuclear palsy: Walking, balance, and eye movements are all affected by this rare neurological condition.
- Restless legs syndrome (RLS): This movement disorder generates uncomfortable leg sensations while lying or relaxing, which are frequently eased by movement.
- Rett syndrome: Rett syndrome is a rare genetic disorder that impairs coordination, hand usage with intent, and speech.
- Tardive dyskinesia: The neuroleptic medications, which are used to treat psychiatric problems, cause this neurological disease when they are administered over an extended period of time. Repetitive and uncontrollable motions including grimacing, eye blinking, and other actions are caused by tardive dyskinesia.
- Tourette syndrome: The brain and nerves are both affected by the neurological condition known as tourette syndrome. It results in sudden movements or sounds (tics), and it is frequently associated by anxiety, ADHD, and obsessive-compulsive disorder.
- Wilson’s disease: Wilson disease is an uncommon hereditary disorder that develops when the body has an excessive amount of copper, particularly in the liver and brain. It may result in tremors, stiff muscles, and uncontrolled movements.
It is crucial to highlight the distinction that conditions such as muscular dystrophy and paralysis, while impacting mobility and weakening muscles, are not classified as movement disorders. This is because they primarily result in impaired movement or muscle weakness. In contrast, movement disorders are characterized by the presence of abnormal movements that are unwanted and disrupt normal motor function.
Movement disorders can cause a wide range of symptoms. Abnormal motions are the result of all movement disorders. Other signs and symptoms of some movement disorders include changes in thinking and mood. From barely noticeable to alarming the symptoms might vary in severity.
The following are typical movement disorder signs and symptoms:
- Uncontrollable motion, such as jerking, twitches, spasms, jerks, twisting, and shaking.
- Balance and coordination issues.
- Difficulty speaking, swallowing, or writing.
- Changes in gait or difficulty walking.
- Rigidity or stiffness in the limbs and trunk.
Intermittent uncontrollable movements, such as hypnic jerks, muscle twitches, or hiccups, can occur in everyone from time to time. However, when these symptoms become persistent or chronic, it may indicate a movement disorder. If an individual notices a consistent change in their own or their child’s movements, it is important to seek medical advice from a healthcare provider for an accurate diagnosis and appropriate treatment. Consulting a healthcare professional can help address any concerns and ensure proper management of the condition.
Movement disorders typically result from malfunctioning or damage to specific regions of the brain that regulate movement, such as the following:
- Primary motor cortex: The frontal lobe contains a strip of brain tissue called the primary motor cortex. It’s in charge of starting voluntary movements. Myoclonus, spasticity, and difficulties with fine motor movements can all be brought on by damage to the primary motor cortex.
- Basal ganglia: The basal ganglia control changes in posture, suppress involuntary movements, and assist in the initiation and smoothing out of voluntary muscle movements. Chorea, athetosis, dystonia, and parkinsonism are all symptoms of damage to the basal ganglia.
- Cerebellum: The cerebellum helps the limbs move naturally and precisely while also assisting in coordination and balance. Loss of coordination arises from damage to this region of the brain.
- Thalamus: In the deeper region of the brain, there are two egg-shaped structures called thalamus, one on each side. All incoming motor (movement) and sensory information is relayed through it. Tremor and motor dysfunction can be brought on by thalamic damage.
These areas may become damaged in a number of situations, including:
- Genetic disorders and changes.
- Traumatic brain injury
- Hereditary or acquired metabolic diseases.
- Vascular illnesses and stroke.
- Side effect from medication.
While healthcare providers are often able to identify the precise cause of certain movement abnormalities, it is important to note that many of these conditions can be attributed to a variety of underlying causes. In fact, there are instances where the exact reasons behind certain movement abnormalities remain unknown.
These conditions can arise from a combination of factors and may require further investigation to determine their specific origins. The complexity of movement abnormalities highlights the need for ongoing research and medical exploration to better understand and address these conditions.