Stereotypic movement disorder is part of a cluster of diagnoses called the motor disorders. Motor disorders are a group of psychiatric conditions that include:
Motor disorders are a group of psychiatric conditions that affect the ability to produce and control bodily movements. Motor disorders may involve developmental delays and deficits involving fine and gross motor functions. Developmental coordination disorder is characterized by deficits in the acquisition and execution of coordinated motor skills and is manifested by clumsiness and slowness or inaccuracy of performance of motor skills that cause interference with daily living. Stereotypic movement disorder includes patterns of repetitive and seemingly driven yet purposeless motor behaviors. Examples of such behaviors include movements of the head, body, and hands that are developmentally abnormal. Tic disorders involve sudden, rapid and recurrent, non-rhythmic motor movements or vocalizations. Such motoric or vocal manifestations are observably involuntary.
Stereotypic movement disorder is a potentially dangerous disorder that occurs in 3-4% of children. Stereotypic movement disorder is characterized by repetitive, seemingly driven, and apparently purposeless motor behavior. This behavior might look like hand shaking or waving body rocking, head banging, self-biting, or hitting one's own body.
Although both tics and stereotypies both involve repetitive, involuntary movements, stereotypies have an earlier age of onset (usually before age 3) and involve the whole body, whereas tics are commonly seen in the eyes, face or head. Tics are also associated with discomfort or stress, whereas stereotypies are self-stimulatory.
Individuals can engage in non-injurious or injurious stereotypic movements that are individually variable. Examples of non-self-injurious stereotypic movements include, but are not limited to, body rocking, bilateral flapping or rotating hand movements, flicking or fluttering fingers in front of the face, arm waving or flapping, and head nodding. Stereotyped self-injurious behaviors include repetitive head banging, face slapping, eye poking, and biting of hands, lips, or other body parts. Multiple movements may be combined (e.g., cocking the head, rocking the torso, waving a small string repetitively in front of the face). The movements can last for more than one minute and can occur several times a day. The frequency and intensity of the behaviors are contingent upon environmental and internal factors. The most common triggers for stereotypic behaviors are excitement, happiness, boredom, anxiety, concentration on a task and fatigue.
Approximately 80% of children who develop motor stereotypies will exhibit symptoms before 24 months of age. The severity of non-self-injurious stereotypic movements ranges from mild presentations that are easily redirected by a sensory stimulus or distraction to continuous movements that severely interfere with all activities of daily living and adaptive functioning.
Self-injurious behaviors range in severity in topography that includes the frequency and severity of bodily injury. The result of self-injurious behavior can vary from mild bruising to retinal detachment from head banging.
There are several risk factors linked to stereotypic movement disorder including social isolation. Children utilize stereotypic movements for self-stimulation and may not seek out social opportunities. Lower cognitive functioning is linked to stereotypic behaviors and poorer response to interventions. Stereotypic movements are frequently found in individuals with intellectual disabilities or autism spectrum disorder. Between 4-16% of individuals with intellectual disability engage in stereotypy and self-injury. Repetitive self-injurious behavior is a common manifestation of several neurogenetic disorders, such as Lesch-Nyhan syndrome, Rett syndrome, fragile X syndrome, Cornelia de Lange syndrome, and Smith-Magenis syndrome.
Stereotypic movement disorder is treatable. Published treatment recommendations for stereotypic movement disorder include those from The Lancet Neurology.
The first step is to develop an individualized and focused working hypothesis on the function of the stereotypic behaviors. This includes setting or antecedent events, factors that maintain the behavior, and the presence of diagnosable primary psychiatric, genetic, neurological, and medical conditions.
Clinical research suggests that the following treatments are indicated for the treatment of children with stereotypic movement disorder:
The first step is to develop an individualized and focused working hypothesis on the function of the stereotypic behaviors. This includes setting or antecedent events, factors that maintain the behavior, and the presence of diagnosable primary psychiatric, genetic, neurological, and medical conditions.
Clinical research suggests that the following treatments are indicated for the treatment of children with stereotypic movement disorder: