Table of contents:
The essential feature of stereotyped movement disorder is repetitive motor behavior, which often appears impulsive and is not functional (Criterion A). This motor behavior interferes with normal activities or results in self-inflicted bodily injury significant enough to require medical treatment (or that it would if protective measures were not taken) (Criterion B). If mental retardation is present, the stereotyped or self-injurious behavior is severe enough to become a therapeutic target (Criterion C).
You may also be interested in: Rumination disorder and pica in childrenStereotyped movement disorder
The behavior is not better explained as a compulsion (as in obsessive-compulsive disorder), a tic (as in tic disorders), a stereotypy that is part of a pervasive developmental disorder, or a hair pull (as in tic disorders). trichotillomania) (Criterion D). The behavior is also not due to the direct physiological effects of a substance or a general medical condition (Criterion E). Motor behaviors must persist for at least 4 weeks (Criterion F). Stereotypical movements may include hand shaking, rocking, hand playing, finger tapping, turning objects, head butting, biting, pricking the skin or body orifices, or hitting different parts of the body.
Sometimes the subject uses an object to perform these behaviors. The behaviors in question can cause permanent and disabling injuries, sometimes endangering the life of the individual. For example, head butting or forceful blows can cause cuts, bleeding, infection, retinal detachment, and blindness. Specifications The clinician can specify with self-injurious behavior if the behavior causes bodily harm requiring specific treatment (or could cause bodily harm if protective measures were not used).
Associated symptoms and disorders
Descriptive characteristics and associated mental disorders. The subject may resort to self-restraint methods (eg, keeping hands under sweater, pants, or pockets) in an attempt to control self-injurious behaviors. When self-restraint is interfered with, behaviors are resumed. If the behaviors are extreme or are repulsive to other people, psychosocial complications may appear due to the exclusion suffered by the subject from certain social and community activities. Stereotyped movement disorder is frequently associated with mental retardation. The more severe the delay, the greater the risk of self-injurious behavior.
This disorder can also appear associated with severe sensory deficits (blindness and deafness) and can be more frequent in institutional settings, where the subject receives insufficient stimulation. Self-injurious behaviors appear in some medical conditions associated with mental retardation (eg, fragile X syndrome, Lange syndrome, and especially Lesch-Nyhan syndrome, which is characterized by severe self-biting). Laboratory findings. If self-injurious behaviors are present, laboratory findings will reflect their nature and severity (eg, anemia from chronic blood loss due to self-inflicted rectal bleeding). Findings of the physical exploration and related medical illnesses.
Signs of chronic tissue injury (eg, bruises, bite marks, cuts, scratches, skin infections, rectal fissures, foreign bodies in body orifices, visual disturbances due to emptying of the eye or traumatic cataract, and fractures from bone deformations). In less severe cases there may be chronic skin irritation or calluses from bites, punctures, scratches or salivary discharge. Age- and sex-dependent symptoms Self-injurious behaviors occur in individuals of any age. There is evidence that head butting is more prevalent in men (approximately 3: 1) and self-biting is more prevalent in women.
Prevalence
There is very little information about the prevalence of stereotyped movement disorder. Estimates of the prevalence of self-injurious behaviors in individuals with mental retardation range from 2 to 3% in children and adolescents living in the community and approximately 25% in adults with severe or profound mental retardation who live in institutions. Course There is no typical age of onset or pattern of onset for stereotyped movement disorder. Such an onset can follow a stressful environmental event. In nonverbal subjects with severe mental retardation, stereotyped movements can be caused by a painful medical condition (eg, a middle ear infection leading to head butting).
Stereotyped movements are usually at their peak in adolescence, and from this point on they can gradually decline. However, especially in subjects with severe or profound mental retardation, the movements can persist for years. The target of these behaviors changes frequently (eg, a person may incur hand biting, the behavior disappear, and then begin to bang their head). Differential diagnosis Stereotyped movements can be associated with mental retardation, especially in subjects located in non-stimulating environments.
Stereotyped movement disorder should only be diagnosed in subjects whose stereotyped or self-injurious behavior is severe enough to be a therapeutic target. Repetitive stereotyped movements are a feature of pervasive developmental disorders. Stereotyped movement disorder is not diagnosed if the stereotypies are better explained by the presence of a pervasive developmental disorder. The compulsions of obsessive-compulsive disorder are often more complex and ritualistic, and are performed in response to an obsession or following rules that must be rigidly applied.
It is relatively easy to differentiate the complex movements characteristic of stereotyped movement disorder from simple tics (eg, blinking), but the differential diagnosis with complex motor tics is less easy. In general, stereotyped movements appear to be more motivated and purposeful, while tics have a more involuntary quality and are not rhythmic.
By definition, repetitive behavior in trichotillomania is limited to hair pulling. The self-induced lesions of stereotyped movement disorder must be distinguished from factitious disorder with a predominance of physical signs and symptoms, where the motivation for self-harm is to assume the role of the patient. Self-mutilation associated with certain psychotic disorders and personality disorders is premeditated, complex, and sporadic, and has meaning for the individual within the context of the underlying severe mental disorder (eg, it is the result of delusional thinking).
The involuntary movements associated with neurological diseases (as in Huntington's disease) usually follow a typical pattern, with the signs and symptoms of the neurological disorder in question being present. Young children's self-stimulating behaviors specific to their level of development (eg, thumb sucking, rocking, and nodding) are often very limited and rarely result in injuries that require treatment. Self-stimulating behaviors in individuals with sensory deficits (eg, blindness) do not usually cause dysfunction or self-harm.
Criteria for the diagnosis of Stereotyped Movement Disorder
- Repetitive, impulsive, and nonfunctional motor behavior (eg, shaking or shaking the hands, rocking the body, butting the head, nibbling on objects, self-eating, poking the skin or body orifices, hitting the body itself).
- The behavior interferes with normal activities or results in self-inflicted bodily injury that requires medical treatment (or would result in injury if preventative measures were not taken).
- If mental retardation is present, the stereotyped or self-injurious behavior is serious enough to be a therapeutic target.
- The behavior is not better explained by a compulsion (as in obsessive-compulsive disorder), a tic (as in tic disorder), a stereotype that is part of a pervasive developmental disorder, or a hair pull (as in trichotillomania).
- The behavior is not due to the direct physiological effects of a substance or to a general medical condition.
- The behavior persists for 4 weeks or more.
Specify if: With self-injurious behavior: if the behavior results in bodily harm requiring specific treatment (or would lead to bodily harm if protective measures were not taken).
This article is merely informative, in Psychology-Online we do not have the power to make a diagnosis or recommend a treatment. We invite you to go to a psychologist to treat your particular case.
If you want to read more articles similar to Stereotyped Movement Disorder, we recommend that you enter our category of Child Psychopathology.