Stereotypic Movement Disorder

What is Stereotypic Movement Disorder?

Overview of stereotypic movement disorder

Stereotypic movement disorder is a repetitive habit disorder where a person (typically a child) engages in uncontrollable repetitive movements (also referred to as stereotypies) for no particular reason. The repetitive movement must continue for a period of at least four weeks and interfere with the child’s daily functions to be considered a disorder, particularly if the movement results in self-injury.

Stereotypic movement disorder typically begins within the first three years of life with different movements more prevalent at different ages, although adolescents and adults can sometimes suffer from this condition as well. While this condition affects more males than females, some specific behaviors are performed by one sex over another; for example, females are more likely to engage in self-biting than males and males are three times more likely to engage in head banging.

Stereotypic movement disorder often is seen in children with intellectual disorders, developmental disabilities, or autism. When a behavioral or neurological disorder is involved, the stereotypic movement disorder is referred to as secondary motor stereotypies.

This condition is typically categorized by three different modes of severity:

  • Mild: Symptoms are not severe and are easily treated by distraction or sensory stimulus
  • Moderate: Symptoms are more severe and may require behavior modification steps
  • Severe: Symptoms require constant monitoring and protective steps to prevent injury to the child

It’s important to remember that many habits appear in children which are perfectly normal, such as foot tapping, rocking, head banging (mildly), thumb sucking, or nail biting, and do not require any sort of treatment. Approximately 20% of the population of healthy children can exhibit repeated movement behavior. However, when behavior is prolonged, these actions can result in negative social interactions at school or with friends and family or in self-injury to the child.

Other types of movements that should not be confused with stereotypies but are also repetitive in nature include the following:

  • Attention deficit hyperactivity disorder (ADHD): tends to be generalized and involve more restless actions
  • Compulsions: repeated movements to relieve fear or anxiety
  • Mannerisms: typically not continued for a prolonged period and are typically normal
  • Tics: usually begin at a later age and are involuntary, repetitive movements for a shorter period of time (stereotypic movement disorder is often misdiagnosed for tics)

Because of the wide range of behaviors and actions associated with stereotypic movement disorder and other conditions, it’s helpful to distinguish between different movements and actions through classification.

General categories of classification include the following:

  • Common stereotypies: These are the most common type of habits in childhood (i.e., bruxism or nail biting)
  • Head nodding: This is classified a separate stereotypy; head nodding shares some features with complex motor stereotypies
  • Complex motor stereotypies: These are associated with repetitive limb movements

Complex motor stereotypies are broken down into the following:

Primary

These stereotypies occur in children with normal development and typically regress in later childhood

Secondary

These stereotypies are associated with a behavioral or neurological disorder such as neurodevelopmental conditions, autism, Tourette’s syndrome, and in intellectually disabled children. Older children may show association with obsessive-compulsive disorder or schizophrenia.

While there are no known specific causes for stereotypic movement disorder, there are conditions that precede symptoms.

Symptoms of stereotypic movement disorder

There are several movements and behaviors associated with stereotypic movement disorder. Many of these symptoms may look familiar and typically aren’t a cause for concern if they are short-term or come with normal child development. However, it’s important to know the symptoms in the event the movements are continual or more severe and self-harm is evident.

Stereotypic movement disorder is indicated by repetitive movements.

Some of the more common movements include the following:

  • Arm waving or hand shaking
  • Self-hitting
  • Skin picking
  • Rocking back and forth
  • Head banging
  • Mouthing of objects
  • Self-biting
  • Excessive nail biting
  • Thumb sucking
  • Trichotillomania
  • Bruxism (teeth grinding)
  • Head nodding
  • Nose picking
  • Breath-holding spells

Repetitive movements that are associated with more complex motor stereotypies include the following:

  • Flapping and waving
  • Wrist extension and flexing
  • Gazing at objects or fingers (typically associated with autism)
  • Abnormal running or skipping (strongly associated with autism)
  • Finger wiggling

The Diagnostic and Statistical Manual of Mental Disorders, 5th Ed. (DSM-5) criteria for diagnosing stereotypic movement disorder with these symptoms include the following:

  • Ongoing repetitive and purposeless motor behavior
  • Repetitive behavior that interferes with normal daily activities, academic progress or social interaction
  • Repetitive behavior that results in self-injury
  • Repetitive behavior that is not explainable by other causes such as medication or a neurological condition

Many of these symptoms take various forms and length of time and severity can vary widely. While stereotypic movement disorder can cause social alienation, stress and possible self-injury, mortality is very rare in these cases.

If any of these symptoms are persistent or are in addition to autism or developmental disabilities, it is important to consult a medical professional and discuss treatment options, of which there are many.

Causes of stereotypic movement disorder

There is no known cause for stereotypic movement disorder, however, there are several conditions that contribute to the onset of this condition.

The following conditions, some more severe than others, are associated with stereotypic movement disorder:

  • Obsessive-compulsive disorder
  • Schizophrenia
  • Autism
  • Abuse or neglect
  • Central nervous system disease
  • Mannerisms
  • Drug poisoning (i.e. amphetamines)
  • Seizure disorder
  • Status epilepticus
  • Pervasive developmental disorder
  • Childhood disintegrative disorder
  • Bobbing head doll syndrome
  • Congenital blindness or deafness
  • Environmentally based sensory deprivation
  • Personality disorders with self-mutilation
  • Psychotic disorders with self-mutilation
  • Self-stimulatory behaviors in individuals with sensory impairments
  • Trichotillomania

While the cause is unknown, it is important to consult with a behavioral pediatrician, a child psychologist or psychiatrist to ensure the child does not do harm to themselves.

There are many symptoms of stereotypic movement disorder, some more severe and atypical than others.

Treatment of stereotypic movement disorder

When stereotypic movement disorder is suspected, a medical professional should be consulted for an examination. If symptoms are present, the doctor will perform a physical exam as well as a developmental history, a family history, and a drug history.

The doctor may first rule out any other causes, such as a physical ailment or effects of any medication that could cause symptoms similar to stereotypic movement disorder. While there are no lab tests to diagnose this condition, there are tests that may be performed such as blood tests or neuroimaging.

Symptoms that are not ongoing or severe and do not interfere with normal functioning often do not require treatment. However, if stereotypic movement disorder is diagnosed, there are several effective treatments available.

Some of the treatments include the following:

  • Behavioral therapy
  • Stress reduction techniques
  • Medication
  • Physical measures (such as dental occlusion splints for bruxism or helmets for head banging)

Behavioral therapy can teach a child an alternative to the repetitive movement. For example, a child that engages in picking the skin can be taught to keep his or her hands in their pockets instead of performing the movement. Functional Communication Training (FTC) rewards children for using verbal responses or alternative actions instead of the repetitive movement.

Differential Reinforcement of Other Behaviors (DRO) rewards children who engage in appropriate behaviors. All of these therapies can help with habit reversal, which is the goal of behavioral therapy. The prognosis for eliminating these habits through behavioral therapies is very good; research has found that typically, this type of intervention can reduce the behavior by 90%.

Medication can be effective in treating stereotypic movement disorder.

Some medications used to treat this disorder include the following:

  • Selective serotonin reuptake inhibitors (SSRIs), including Zoloft, Prozac, or Luvox
  • Atypical antipsychotics such as aripiprazole or risperidone (sometimes used for children with autism disorders)
  • Tricyclic antidepressants such as Aranfranil
  • Neuroleptics (these are not often used because of adverse side effects)

Other therapies for habits (either severe or not) include the following:

  • Self-monitoring
  • Relaxation techniques
  • Positive reinforcement Competing responses
  • Use of bad-tasting substances for nail biting or thumb sucking

If the child is engaging in self-harming behaviors, adjustments to the child’s environment may need to take place to ensure safety.

Most common cases of stereotypic movement disorder have a positive prognosis. Most stereotypies that occur in infancy usually stabilize or disappear in later childhood.

Most habits that develop in childhood and do not involve social disruption or self-injury are typical and can be resolved without therapy or any sort of intervention. Complex motor stereotypies are known to be present in more children than once thought.

While stereotypic movement disorder may not be preventable, there are some measures that can be taken to prevent habits that are developing before they result in more serious disorders.

Prevention of stereotypic movement disorder

Stereotypic movement disorder is not a preventable condition, however, there are steps that can be taken to reduce the risk of self-injury and to help the child live a more normal functional life. It’s also important to know that there are measures that can be taken to prevent intellectual disorders in children during the prenatal stages of development.

Research shows that behavior modification therapy has been found to help prevent further episodes of stereotypic movement disorder. Studies show that habit reversal, a behavioral therapy technique, is effective in both organic and behavioral stereotypies. Habit reversal involves two major steps to be effective. The first is awareness training, which involves helping the patients become aware of their repetitive movements by encouraging them to exhibit the repetitive behavior. Once awareness is obtained, patients are trained to refrain from repetitive behavior and substitute it with another behavior.

There are measures that can be taken to prevent intellectual disabilities in children that lead to stereotypic movement disorder.

Medical conditions that can cause intellectual disabilities include the following:

  • Prenatal exposure to infections
  • Prenatal exposure to drugs and alcohol
  • Prenatal exposure to toxins
  • Brain injury to children

One of the leading causes of intellectual disabilities in children is fetal alcohol syndrome (FAS). Staying away from any form of alcohol during pregnancy is essential to ensuring the health of the baby. Drugs such as cocaine, nicotine, and heroin can also cause harm to a fetus in the developmental stage and should be avoided.

Avoiding exposure to toxins, including mercury, lead, and radiation, is important during pregnancy. These toxins can be found in paint in older homes (pre-1970) as well as in the surrounding soil. Fish such as mackerel and swordfish, along with other large fish, can contain high levels of mercury. While radiation exposure due to x-rays and other medical procedures is relatively safe, pregnant women should refrain from such conditions or let their doctor know before having any procedure involving radiation performed.

Infections, such as those caused by cat feces, can be easily avoided by pregnant women by not going near cat feces or refraining from cleaning a cat litter box. Practicing safe sex will reduce the chance of sexually transmitted diseases and infections, for which exposure could harm a fetus.

Brain injury is mostly preventable in children. Care should be taken when transporting children by using approved safety seats. Also, children should wear helmets when riding bikes.

Taking a few preventative steps during prenatal care and when children are infants can prevent intellectual disabilities, thus reducing the chance for stereotypic movement disorder.

Some habits in childhood are normal, such as thumb-sucking, and will regress with time. However, if the repetitive movement is resulting in self-injury or having a negative impact on social functioning, it’s important to get treatment as soon as possible. Left untreated, stereotypic movement disorder can result in distress, social rejection, academic problems, psychological issues such as guilt, shame or stress, and depression in children that can severely impact childhood.