What are Movement Disorders?
Movement disorders in children are frequently seen in a broad spectrum of neurological conditions, from benign, self-limiting transient phenomena to progressive disorders associated with significant motor impairment. Clinical presentations may be acute, subacute or chronic.
What Are the Types of Movement Disorders?
In general, Movement Disorders can be divided into:
- Hyperkinesia (too much movement) or Dyskinesia (abnormal movement) – such as tics, dystonia, myoclonus, chorea, athetosis, tremor and stereotypies
- Hypokinesia-rigid syndrome (too little or lack of movement) – i.e. Parkinsonism, which is rather rare in children
| Definitions | |
|---|---|
|
Tics |
Brief involuntary purposeless movements and/or sounds. |
|
Dystonia |
Sustained or intermittent muscle contractions causing abnormal, often repetitive, movements, postures, or both. Typically patterned, twisting, and may be tremulous. Dystonia is often initiated or worsened by voluntary action and associated with overflow muscle activation. |
|
Myoclonus |
Sudden, brief involuntary jerk of a muscle or a group of muscles |
|
Chorea |
Rapid, abrupt, irregular, unpredictable, non-stereotyped, semi or non-purposeful movement. |
|
Athetosis |
Slow continuous stream of writhing movement, typically of the hands and feet. |
|
Tremor |
Involuntary, rhythmic, oscillatory movement of a body part |
|
Stereotypies |
Repetitive and purposeless movements |
What are the Movement Disorders presenting in childhood?
1. BENIGN MOVEMENT DISORDERS OF CHILDHOOD
A number of benign movement disorders of childhood are recognised, and they are transient in nature, and usually have a good long-term prognosis.
Neonatal Jitteriness
- High frequency and low amplitude tremor
- Location: jaw and extremities
- Multiple factors, including metabolic disturbance, Hypoxic-Ischaemic Encephalopathy (HIE), drug withdrawal
- Often mistaken for neonatal seizures
- Suppressed easily by gentle restraint
- No specific treatment; treat the underlying factors
- Usually resolves by 7 months
Benign neonatal sleep myoclonus
- Self-limiting movement disorder
- Myoclonic jerks during non-rapid eye movement (NREM)/ quiet sleep
- Stopped by arousal
- Usually resolves by 3 to 4 months
Benign Polymorphous Movement Disorders of Infancy (BPMDI)
A heterogeneous group of movement disorders, including shuddering attacks, benign myoclonus of early infancy, head nodding, benign infantile shaking body attacks, brief tonic contraction, benign non-epileptic infantile spasms, and sleep related infantile tremor.
Characteristic features:
- Onset: 4 to 7 months
- Paroxysmal, sometimes in clusters
- Brief event
- Without impaired consciousness
- Several times on a daily basis
- Usually triggered by excitement, frustration or postural changes
- Normal developmental milestones, and normal neurology
- Resolved spontaneously
Transient idiopathic dystonia of infancy
- Onset is usually before 5 months
- Hemidystonia – usually affecting single upper limb and trunk
- Movement stopped when infant moves purposefully
- Resolves without any complications around 1 year of age
Motor Stereotypies/ Stereotypic Movement Disorder
- Repetitive, seemingly driven, purposeless motor behaviour
- Early onset
- Usually persists more than 4 weeks
- May interfere with normal activities, or results in self injury
Primary Motor Stereotypies
- Common among normal children
- Transient in nature;
- Good prognosis
- Common Behavioural stereotypies, such as rocking, head banging, hair twisting, pencil tapping
- Complex stereotypies: head nodding, hand shaking, opening/ closing of hands, arm flapping, flexion/ extension of wrists, mouth opening/ facial grimaces
Secondary Motor Stereotypies
- Commonly seen in Autistic Spectrum Disorders, Rett syndrome, Angleman Sydnrome, Neurogenetic disorders and Neurometabolic disorders.
2. TICS & TOURETTE SYNDROME
Please click Tics & Tourette Syndrome (妥瑞症) for further details.
3. DYSTONIA
Dystonia is characterised by sustained or intermittent muscle contractions that cause abnormal, often repetitive, movements, postures, or both. It is typically patterned and twisting and may be tremulous. It is usually initiated or worsened by voluntary action and is associated with overflow muscle activation.
Causes of childhood dystonia:
- Primary Dystonia, e.g. Dopa Responsive Dystonia
- Secondary Dystonia, eg. Cerebral Palsy, Neurometabolic disorders, Neurodegenerative disorders
What Causes Movement Disorders?
Our brain cells speak to one another with electrical signals, and these are conducted by special brain chemicals called neurotransmitters. Movement Disorders arise as a result of disturbances or imbalance of these neurotransmitters (i.e. software issue), or due to structural abnormalities (hardware issue) in the areas of the brain, called basal ganglia, that control movement.
The imbalance of neurotransmitters can be caused by several factors or causes, such as structural, metabolic, infectious, immunological, genetic or inherited causes, or a combination of the above causes, or idiopathic (no known cause)
For example:
- Structural cause – Acquired brain injury, Cerebral Palsy (CP)
- Metabolic cause – Lech-Nyhan Disease causing generalised dystonia
- Immunological cause – Anti-NMDAR antibodies encephalitis
- Genetic cause – Chromosomal abnormalities
What Are The Common Co-Occurring Conditions?
Children with movement disorders may experience a variety of co-occurring conditions that can impact their overall health and well-being. Some common co-occurring conditions include:
Neurodevelopmental Disorders & Learning Disability
Children with movement disorders may have mild, moderate or severe learning disability. The current research supports that the underlying cause of movement disorder may impact on neurodevelopment. Hence, children and young people with movement disorders may also have neurodevelopment disorders such as Attention Deficit Hyperactivity Disorder (ADHD) and autistic spectrum disorder (ASD), and Obsessive Compulsive Disorder (OCD).
Epilepsy and Epileptic Seizures
Some children with movement disorders may experience epileptic seizures. These seizures can vary in type and severity and may require treatment with anti-seizure medications.
Sleep Disorders
Sleep disturbances such as sleep apnea, insomnia, or disrupted sleep patterns are more common in children with movement disorder (up to 30%) and may affect overall health and quality of life.
Gastrointestinal Issues
Gastrointestinal problems such as gastroesophageal reflux disease (GERD), constipation, difficulty swallowing (dysphagia), and salivary drooling are common in children with generalised dystonia/ movement disorders. Proper management and dietary modifications may be necessary to address these issues.
Orthopaedic Complications
Up to 30% of children with long-term neurological conditions, such as dystonia, can lead to musculoskeletal issues such as hip subluxation/ dislocation, scoliosis,and joint deformities due to muscle stiffness or muscle weakness. Physical therapy, pharmacological treatments, orthotic devices or surgical interventions may be required to manage these complications.
Sensory problems (Visual & Hearing problems)
Depending on the cause of the movement disorders, visual impairments, which may include strabismus (crossed eyes), nystagmus (involuntary eye movements), or cortical visual impairment. Regular ophthalmological assessment and interventions may be necessary.
Children with movement disorders may also experience hearing impairments, either due to congenital factors, complications of prematurity, or repeated ear infections. Hearing assessment and appropriate interventions are essential for optimal communication and development.
Behavioural and Emotional Challenges
Living with a long-term neurological condition like dystonia can impact emotional well-being. It may contribute to behavioural and psycho-emotional challenges such as anxiety, depression, or social interaction difficulties.
Several studies of children and adults with movement disorders have shown that high proportion of patients had anxiety, depression, or mixed mental health disorders.
How to diagnose Movement Disorders or Dystonia?
Diagnosing movement disorder in children involves a thorough evaluation by a paediatric neurologist, including medical history, physical examination, developmental assessment, and neurological evaluation.
During your appointment, Dr Yeo will want to know as much as possible about the nature of the abnormal movement.
It will help Dr Yeo by providing the following information:
- Diary of your child’s event or abnormal movement (dates, times, description of what had happened before/during/ after the event)
- Video recording of your child’s abnormal movement (if possible)
- Bring along the individual who had witnessed your child’s event or get a written description from the individual who had witnessed your child’s event would be very helpful!
Dr Yeo may suggest the following tests to help with the diagnosis and management of the abnormal movement or movement disorder:
- Electroencephalogram (EEG) : This is a brain-wave recording which involves applying quite a few sticky sensors on your child’s head. This is a painless procedure.
- Magnetic Resonance Imaging (MRI) of the brain: These are detailed pictures of the brain to evaluate the structure of your child’s brain.
- Comprehensive neurometabolic testing and/ or genetic testing may be offered to identify underlying metabolic or genetic causes.
Early diagnosis and appropriate treatments are crucial for optimising long term neuro-developmental outcomes and providing appropriate support for children with dystonia or other movement disorders and their families.
How do we treat Movement Disorder?
Once your child is diagnosed with a movement disorder, Dr. Yeo will work with you to create a personalised treatment plan. This plan will consider all aspects of your child’s lifestyle and situation and your family’s preferences.
Dr Yeo may also collaborate with you and your child to create a Dystonia Action Plan, which is an emergency plan to follow when an intrusive dystonia occurs. This plan will include vital information about your child’s medical history, dystonia/ movement disorders, and regular and emergency medication plans.
After considering all of these aspects, Dr. Yeo will guide you and your child in finding the proper treatment; There are a number of different treatments that can reduce the symptoms of dystonia and other movement disorders:
Oral medication
Specific anti-dystonic/ dyskinetic medications exist, such as L-dopa, Trihexyphenidyl, Clonidine, Gabapentin, and Tetrabenazine. These medicines work by modulating or stabilising the abnormal electrical signals of the brain cells or restoring the chemical imbalance.
Other medications may be prescribed to manage symptoms associated with movement disorders, such as pain, spasticity (muscle stiffness), seizures, or gastrointestinal issues. Common medications include muscle relaxants, anti-seizure medications, pain relievers, and medications for reflux or constipation.
Dr Yeo will discuss with you about which medicines have been found to work well, or not work well, for your child’s particular movement disorder, and also the pros and cons of each medicine or other treatment options.
Botulinum Toxin Therapy (Botox)
Botulinum toxin therapy temporarily reduces muscle spasticity or dystonia, and it aims to improve the range of motion, preserve joint alignment, and to improve ease of comfort and care. They are commonly used in conjunction with physical and/or occupational therapy, serial casting and orthotic devices to facilitate stretching exercises, standing and functional activities.
Please click here for additional information about Botulinum Toxin Therapy.
Physical Therapy
Physical therapy focuses on improving muscle strength, flexibility, balance, posture and mobility through exercises and specific therapeutic techniques for tackling movement disorders. It may also include training in activities of daily living and the use of assistive devices such as braces or walkers.
Occupational Therapy
Occupational therapy helps individuals develop skills for daily tasks, such as dressing, feeding, and writing, to promote independence and improve quality of life. It may involve adaptive equipment and techniques tailored to the individual’s needs.
Speech Therapy
Speech therapy addresses communication difficulties, swallowing problems (dysphagia), and oral motor issues commonly associated with movement disorders. Therapists work to improve speech clarity, language skills, and swallowing function.
There are other treatment options which may be suggested if they are appropriate:
Intrathecal Baclofen Therapy (ITB)
Generalised dystonia or spasticity can be treated with physiotherapy and oral medications such as Baclofen, but these are sometimes ineffective or have unacceptable side effects due to high dosage. Intrathecal baclofen treatment involves injecting medication into the cerebrospinal fluid which surrounds the spinal cord. A pump implanted in the abdomen injects baclofen into the cerebrospinal fluid, increasing the drug’s effectiveness and reducing adverse events.
Intrathecal baclofen (ITB) therapy has demonstrated a dramatic improvement in severe generalised dystonia/ spasticity together with long-term safety.
Deep Brain Stimulation (DBS)
Deep brain stimulation (DBS) is a neurosurgical procedure that involves the implantation of two thin electrodes into the brain. These electrodes are connected by a wire placed under the skin to a battery, which is usually implanted in the chest or abdomen. The battery works similarly to a pacemaker, by delivering targeted electrical pulses that modulate the signals causing dystonia.
References
Dr Yeo’s recent peer-group review journal publications and relevant articles regarding Cerebral Palsy (CP) and Long Term Neurological Conditions (LTNC):
Chia, Aletheia & Tan, Yi & Yeo, Tong & Teoh, Oon & Ng, Zhi Min. (2022). Epidemiology and risk factors for sleep disturbances in children and youth with cerebral palsy: An ICF-based approach. Sleep Medicine. 96. 10.1016/j.sleep.2022.04.021.
Leow, XYJ & Tan, JTC & Yeo, Tong & Wong, Kenneth & Mahadev, Arjandas & Ang, Bixia & Vasanwala, Rashida & Ng, Zhi Min. (2021). Evaluation of risk factors associated with fragility fractures and recommendations to optimise bone health in children with long-term neurological condition. Singapore Medical Journal. 64. 10.11622/smedj.2021124.
Ng, Zhi Min & Lin, Jeremy & Khoo, Poh & Rajadurai, Victor & Chan, Derrick & Ong, Hian & Wong, Janice & Choong, Chew & Lim, Kim & Lim, Kevin & Yeo, Tong. (2021). Causes, functional outcomes and healthcare utilisation of people with cerebral palsy in Singapore. Annals of the Academy of Medicine, Singapore. 50. 111-118. 10.47102/annals-acadmedsg.2020489.
KKH Hip Surveillance Programme for Children with Long term Neurological Conditions
Special Delivery, Issue 3, March 2018
(By Dr Ng Zhi MIn, Dr Yeo Tong Hong, A/Prof Arjandas Mahadev)
Special Delivery, Issue 3, March 2018
(By Dr Ng Zhi MIn, Dr Yeo Tong Hong, A/Prof Arjandas Mahadev)
Yeo TH, Brooks L, Differences in perceptions of palliative care needs for children with neurological conditions. Support Palliat Care 2012;2:A18.
Research Trials
– Co-investigator, Singapore Cerebral Palsy Registry, 2017 – ongoing research project
– Local principal investigator, Royal Hospital for Children, Glasgow, UKMCRN trial – ‘The efficacy, safety and tolerability of nabiximols (Sativex) as an adjunctive treatment to existing anti-spasticity medications in children aged 8 to 18 years with spasticity due to cerebral palsy who have not responded adequately to their existing anti-spasticity medications: a parallel group randomised, double-blind, placebo-controlled study’, 2014 – 2016.
