DSM-IV-TR › Disorders usually first diagnosed in infancy, childhood, or adolescence › Other disorders of infancy, childhood, or adolescence › Stereotypic movement disorder (formerly stereotypy/habit disorder) 

307.3 Stereotypic Movement Disorder (formerly Stereotypy/Habit Disorder)

Diagnostic Features

The essential feature of Stereotypic Movement Disorder is motor behavior that is repetitive, often seemingly driven, and nonfunctional (Criterion A). This motor behavior markedly interferes with normal activities or results in self-inflicted bodily injury that is significant enough to require medical treatment (or would result in such injury if protective measures were not used) (Criterion B). If Mental Retardation is present, the stereotypic or self-injurious behavior is sufficiently severe to become a focus of treatment (Criterion C). The behavior is not better accounted for by a compulsion (as in Obsessive-Compulsive Disorder), a tic (as in the Tic Disorders), a stereotypy that is part of a Pervasive Developmental Disorder, or hair pulling (as in Trichotillomania) (Criterion D). The behavior is also not due to the direct physiological effects of a substance or a general medical condition (Criterion E). The motor behaviors must persist for at least 4 weeks (Criterion F).

The stereotypic movements may include hand waving, rocking, playing with hands, fiddling with fingers, twirling objects, head banging, self-biting, or hitting various parts of one's own body. Sometimes the individual uses an object in performing these behaviors. The behaviors may cause permanent and disabling tissue damage and may sometimes be life-threatening. For instance, severe head banging or hitting may lead to cuts, bleeding, infection, retinal detachment, and blindness.

Specifiers

The clinician may specify With Self-Injurious Behavior if the behavior results in bodily damage that requires specific treatment (or that would result in bodily damage if protective measures were not used).

Associated Features and Disorders

Associated descriptive features and mental disorders.

The individual (especially an individual with Lesch-Nyhan syndrome) may develop methods of self-restraint (e.g., holding hands inside shirts, trousers, or in pockets) to attempt to control the self-injurious behaviors. When the self-restraint is interfered with, the behaviors return. If the behaviors are extreme or repulsive to others, there may be psychosocial complications due to the individual's exclusion from social and community activities. Stereotypic Movement Disorder occurs most commonly in association with Mental Retardation. The more severe the retardation, the higher the risk for self-injurious behaviors. The disorder can also occur in non-developmentally delayed populations (e.g., individuals with body rocking associated with Generalized Anxiety Disorder).

This disorder may also occur in association with severe sensory deficits (blindness and deafness) and may be more common in institutional environments in which the individual receives insufficient stimulation. Self-injurious behaviors occur in certain general medical conditions associated with Mental Retardation (e.g., f ragile X syndrome, Down syndrome, de Lange syndrome, and especially Lesch-Nyhan syndrome, which is characterized by severe self-biting).

Associated laboratory findings.

If there is self-injury, the laboratory findings will reflect its nature and severity (e.g., anemia may be present if there is a chronic blood loss from self-inflicted rectal bleeding).

Associated physical examination findings and general medical conditions.

Signs of chronic tissue damage may be present (e.g., bruises, bite marks, cuts, scratches, skin infections, rectal fissures, foreign bodies in bodily orifices, visual impairment due to eye gouging or traumatic cataract, and fractures or deformed bones). In less severe cases, there may be a chronic skin irritation or calluses from biting, pinching, scratching, or saliva smearing.

Specific Age and Gender Features

Self-injurious behaviors occur in individuals of all ages. There are indications that head banging is more prevalent in males (with about a 3:1 ratio), and self-biting may be more prevalent in females.

Prevalence

There is limited information on the prevalence of Stereotypic Movement Disorder. The estimates of prevalence of self-injurious behaviors in individuals with Mental Retardation vary from 2% and 3% in children and adolescents living in the community to approximately 25% in adults with severe or profound Mental Retardation living in institutions.

Course

There is no typical age at onset or pattern of onset for Stereotypic Movement Disorder. The onset may follow a stressful environmental event. In nonverbal individuals with Severe Mental Retardation, stereotypic movements may be triggered by a painful general medical condition (e.g., a middle ear infection leading to head banging). The stereotypic movements often peak in adolescence and then may gradually decline. However, especially in individuals with Severe or Profound Mental Retardation, the movements may persist for years. The focus of these behaviors often changes (e.g., a person may engage in hand biting that may then subside and head hitting may emerge).

Differential Diagnosis

Stereotypic movements may be associated with Mental Retardation, especially for individuals in nonstimulating environments. Stereotypic Movement Disorder should be diagnosed only in individuals in whom the stereotypic or self-injurious behavior is of sufficient severity to become a focus of treatment. Repetitive stereotyped movements are a characteristic feature of Pervasive Developmental Disorders. Stereotypic Movement Disorder is not diagnosed if the stereotypies are better accounted for by a Pervasive Developmental Disorder. Compulsions in Obsessive-Compulsive Disorder are generally more complex and ritualistic and are performed in response to an obsession or according to rules that must be applied rigidly. Differentiating the complex movements characteristic of Stereotypic Movement Disorder from simple tics (e.g., eye blinking) is relatively straightforward. However, differentiating Stereotypic Movement Disorder from complex motor tics can be quite difficult, given the similarities between the two in terms of intentionality, rhythmicity, and drivenness.

In Trichotillomania, by definition, the repetitive behavior is limited to hair pulling. The self-induced injuries in Stereotypic Movement Disorder should be distinguished from Factitious Disorder With Predominantly Physical Signs and Symptoms, in which the motivation of the self-injury is to assume the sick role. Self-mutilation associated with certain Psychotic Disorders and Personality Disorders is premeditated, complex, and sporadic and has a meaning for the individual within the context of the underlying, severe mental disorder (e.g., is the result of delusional thinking). Involuntary movements associated with neurological conditions (such as Huntington's disease) usually follow a typical pattern, and the signs and symptoms of the neurological condition are present. Tardive Dyskinesia usually results from chronic neuroleptic use and consists of characteristic orofacial dyskinesias or, less commonly, irregular truncal or limb movements. In addition, these types of movements do not result in direct self-injury.

Developmentally appropriate self-stimulatory behaviors in young children (e.g., thumb sucking, rocking, and head banging) are usually self-limited and rarely result in tissue damage requiring treatment. Self-directed behaviors in individuals with sensory deficits (e.g., blindness) are repetitive and stereotyped but usually do not result in dysfunction or in self-injury.

Many people engage in repetitive behaviors for various reasons (practicing to improve a motor skill, culturally sanctioned practices). In contrast to Stereotypic Movement Disorder, these behaviors do not interfere with normal activities nor do they result in self-injury.

Diagnostic criteria for 307.3 Stereotypic Movement Disorder

1. Repetitive, seemingly driven, and nonfunctional motor behavior (e.g., hand shaking or waving, body rocking, head banging, mouthing of objects, self-biting, hitting own body).
2. The behavior markedly interferes with normal activities or results in self-inflicted bodily injury that requires medical treatment (or would result in an injury if preventive measures were not used).
3. If Mental Retardation is present, the stereotypic or self-injurious behavior is of sufficient severity to become a focus of treatment.
4. The behavior is not better accounted for by a compulsion (as in Obsessive-Compulsive Disorder), a tic (as in Tic Disorder), a stereotypy that is part of a Pervasive Developmental Disorder, or hair pulling (as in Trichotillomania).
5. The behavior is not due to the direct physiological effects of a substance or a general medical condition.
6. The behavior persists for 4 weeks or longer.

Specify if:

With Self-Injurious Behavior: if the behavior results in bodily damage that requires specific treatment (or that would result in bodily damage if protective measures were not used)

Reprinted with permission from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision^TM. Copyright 2000 American Psychiatric Association. All Rights Reserved.