Phenomenology of psychogenic movement disorders in children

Psychogenic non-epileptic seizures and functional motor disorders in developmental age: A comparison of clinical and psychopathological features

BACKGROUND

Psychogenic Non-Epileptic Seizures (PNES) and Functional Motor Disorders (FMDs) commonly represent the main clinical manifestations of Functional Neurological Disorders (FNDs). Despite their high prevalence in pediatric neurological services, literature on this topic is still spare for this population. The present study aimed to deepen the clinical knowledge of a pediatric FNDs sample through a demographic and clinical characterization of the most recurrent clinical patterns during the pediatric age. Moreover, a comparison of neuropsychological and psychopathological profiles of PNES and FMD patients was carried out to identify specific vulnerabilities and therapeutic targets linked with these different clinical manifestations.

MATERIALS AND METHODS

A total of 43 FNDs patients (age range 7-17 years old) were retrospectively included in our study, enrolled in two subgroups: 20 with FMDs and 23 with PNES diagnosis. They were inpatients and outpatients referred over a period of 5 years and a standardized neurological, neuropsychological (WISC-IV/WAIS-IV), and psychiatric (CDI-2, MASC-2, ADES, DIS-Q, PID-5) evaluation was assessed.

RESULTS

In PNES patients the most common clinical phenotypes were functional tonic-clonic (52%) and atonic (32%) manifestations while in the FMDs group were gait alterations (60%), functional myoclonus (35%), and tremor (35%). A higher frequency of cognitive impairment was reported in PNES patients with higher anxiety-depressive symptom rates than FMDs patients.

CONCLUSIONS

Notably, specific neurocognitive and psychopathological profiles were described in PNES and FMDs, highlighting higher cognitive and psychiatric vulnerabilities in PNES, suggesting as well different strategy for therapeutic approaches.

Diagnosis and Initial Treatment of Functional Movement Disorders in Children

Functional movement disorders (FMD) are complex neurobehavioral disorders that can be a significant source of disability for both children and their caregivers. While FMD in the adult population is better characterized, the aim of this paper is to review the pertinent clinical and historical features, diagnostic criteria, and multi-disciplinary management of FMD in the pediatric population. We highlight recent trends in pediatric FMD, including the increase in functional tic-like behaviors that has been observed during the COVID-19 pandemic.

A Review and Expert Opinion on the Neuropsychiatric Assessment of Motor Functional Neurological Disorders

Functional neurological (conversion) disorder (FND) is a prevalent and disabling condition at the intersection of neurology and psychiatry. Advances have been made in elucidating an emerging pathophysiology for motor FND, as well as in identifying evidenced-based physiotherapy and psychotherapy treatments. Despite these gains, important elements of the initial neuropsychiatric assessment of functional movement disorders (FND-movt) and functional limb weakness/paresis (FND-par) have yet to be established. This is an important gap from both diagnostic and treatment planning perspectives. In this article, the authors performed a narrative review to characterize clinically relevant variables across FND-movt and FND-par cohorts, including time course and symptom evolution, precipitating factors, medical and family histories, psychiatric comorbidities, psychosocial factors, physical examination signs, and adjunctive diagnostic tests. Thereafter, the authors propose a preliminary set of clinical content that should be assessed during early-phase patient encounters, in addition to identifying physical signs informing diagnosis and potential use of adjunctive tests for challenging cases. Although clinical history should not be used to make a FND diagnosis, characteristics such as acute onset, precipitating events (e.g., injury and surgery), and a waxing and waning course (including spontaneous remissions) are commonly reported. Active psychiatric symptoms (e.g., depression and anxiety) and ongoing psychosocial stressors also warrant evaluation. Positive physical examination signs (e.g., Hoover's sign and tremor entrainment) are key findings, as one of the DSM-5 diagnostic criteria. The neuropsychiatric assessment proposed emphasizes diagnosing FND by using "rule-in" physical signs while also considering psychiatric and psychosocial factors to aid in the development of a patient-centered treatment plan.

Functional dystonia: A case-control study and risk prediction algorithm

OBJECTIVE

Functional dystonia (FD) is a disabling and diagnostically challenging functional movement disorder (FMD). We sought to identify historical predictors of FD vs. other primary dystonias (ODs) and develop a practical prediction algorithm to guide neurologists.

METHODS

1475 consecutive new patient medical records were reviewed at an adult/pediatric tertiary-referral dystonia clinic from 2005 to 2017. Ninety-nine met criteria for clinically established FD (85 adults and 14 pediatric), paired with 99 age/dystonia distribution-matched OD. Univariate and multivariate regression analyses were performed to identify predictors of FD and disability. We formed a prediction algorithm, assessed using the area under the receiver operating curve (AUC).

RESULTS

Multivariate logistic regression analysis investigating independent predictors of FD (P < 0.001) followed by development of a prediction algorithm showed that the most robust predictors included abrupt onset, spontaneous resolution/recurrence, pain, cognitive complaints, being on or pursuing disability, lifetime mood/anxiety disorder, comorbid functional somatic disorders, and having ≥3 medication allergies. The prediction algorithm had utility for both adult and pediatric FD, with excellent sensitivity/specificity (89%/92%) and an area under the curve (AUC) 0.95 (0.92-0.98). Greater disability (modified Rankin Scale) independently correlated with a number of functional examination features, unemployment/not attending school, number of medication allergies, and younger age of presentation. FD patients were high health-care utilizers and were more frequently prescribed opiates/opioids and benzodiazepines (P < 0.003).

INTERPRETATION

This case-control study provides an algorithm to guide clinicians in gauging their index of suspicion for a FD, with diagnostic confirmation subsequently informed by neurological examination. While this algorithm requires prospective validation, health-care utilization data underscore the importance and need for more research in FD.

Functional Dystonia: Differentiation From Primary Dystonia and Multidisciplinary Treatments

Dystonia is a common movement disorder, involving sustained muscle contractions, often resulting in twisting and repetitive movements and abnormal postures. Dystonia may be primary, as the sole feature (isolated) or in combination with other movement disorders (combined dystonia), or as one feature of another neurological process (secondary dystonia). The current hypothesis is that dystonia is a disorder of distributed brain networks, including the basal ganglia, cerebellum, thalamus and the cortex resulting in abnormal neural motor programs. In comparison, functional dystonia (FD) may resemble other forms of dystonia (OD) but has a different pathophysiology, as a subtype of functional movement disorders (FMD). FD is the second most common FMD and amongst the most diagnostically challenging FMD subtypes. Therefore, distinguishing between FD and OD is important, as the management of these disorders is distinct. There are also different pathophysiological underpinnings in FD, with for example evidence of involvement of the right temporoparietal junction in functional movement disorders that is believed to serve as a general comparator of internal predictions/motor intentions with actual motor events resulting in disturbances in self-agency. In this article, we present a comprehensive review across the spectrum of FD, including oromandibular and vocal forms and discuss the history, clinical clues, evidence for adjunctive "laboratory-based" testing, pathophysiological research and prognosis data. We also provide the approach used at the Massachusetts General Hospital Dystonia Center toward the diagnosis, management and treatment of FD. A multidisciplinary approach, including neurology, psychiatry, physical, occupational therapy and speech therapy, and cognitive behavioral psychotherapy approaches are frequently required; pharmacological approaches, including possible targeted use of botulinum toxin injections and inpatient programs are considerations in some patients. Early diagnosis and treatment may help prevent unnecessary investigations and procedures, while facilitating the appropriate management of these highly complex patients, which may help to mitigate frequently poor clinical outcomes.

Functional Movement Disorders in Children

Functional movement disorders (FMDs) are not uncommon in children. The age at onset may have a bearing on the phenomenological pattern of abnormal movement, risk factors, and response to different treatment modalities in this age group. FMDs in children resemble their adult counterparts in terms of gender preponderance, but risk factors are quite different, and often influenced by cultural and demographic background. FMDs contribute to a significant proportion of acute pediatric movement disorder patients seen in emergency settings, ranging from 4.3 to 23% in different case series. The most common movement phenomenologies observed in pediatric FMDs patients are tremor, dystonia, gait disturbances, and functional tics. Various social, physical, and familial precipitating factors have been described. Common social risk factors include divorce of parents, sexual abuse, bullying at school, examination pressure, or other education-related issues, death of a close friend, relative, or family members. Physical trauma like minor head injury, immunization, tooth extraction, and tonsillectomy are also known to precipitate FMDs. The response to treatment appears to be better among pediatric patients. We aim to review FMDs in children to better understand the different aspects of their frequency, clinical features, precipitating factors, diagnosis, treatment, and outcome.

Current challenges in the pathophysiology, diagnosis, and treatment of paroxysmal movement disorders

INTRODUCTION

Paroxysmal movement disorders mostly comprise paroxysmal dyskinesia and episodic ataxia, and can be the consequence of a genetic disorder or symptomatic of an acquired disease.

AREAS COVERED

In this review, the authors focused on certain hot-topic issues in the field: the respective contribution of the cerebellum and striatum to the generation of paroxysmal dyskinesia, the importance of striatal cAMP turnover in the pathogenesis of paroxysmal dyskinesia, the treatable causes of paroxysmal movement disorders not to be missed, with a special emphasis on the treatment strategy to bypass the glucose transport defect in paroxysmal movement disorders due to GLUT1 deficiency, and functional paroxysmal movement disorders.

EXPERT OPINION

Treatment of genetic causes of paroxysmal movement disorders is evolving towards precision medicine with targeted gene-specific therapy. Alteration of the cerebellar output and modulation of the striatal cAMP turnover offer new perspectives for experimental therapeutics, at least for paroxysmal movement disorders due to selected causes. Further characterization of cell-specific molecular pathways or network dysfunctions that are critically involved in the pathogenesis of paroxysmal movement disorders will likely result in the identification of new biomarkers and testing of innovative-targeted therapeutics.

Pediatric Functional Movement Disorders: Experience from a Tertiary Care Centre

Objectives:

Functional movement disorders (FMDs) pose significant diagnostic and management challenges. We aimed to study the socioeconomic and cultural factors, underlying psychopathology and the phenomenology of FMDs in children.

Methods:

The study is a retrospective chart review of 39 children (16 girls and 23 boys) who attended our neurology OPD and the movement disorders clinic at the National Institute of Mental Health and Neurosciences (NIMHANS) between January 2011 and May 2020. The diagnosis of FMD was based on Fahn and Williams criteria and the patients were either diagnosed as “documented” or “clinically established”. All the relevant demographic data including the ethnicity, socioeconomic and cultural background, examination findings, electrophysiological, and other investigations were retrieved from the medical records.

Results:

The mean age at onset was 12.69 ± 3.13 years. Majority of the children were from urban regions (56.41%) and belonging to low socioeconomic status (46.15%). Thirty (76.92%) were found to have a precipitating factor. Myoclonus was the most common phenomenology observed in these patients (30.76%), followed by tremor (20.51%), dystonia (17.94%), and gait abnormality (7.69%). Chorea (5.12%) and tics (2.56%) were uncommon. Tremor (37.5%) and dystonia (18.75%) were more common in girls, whereas myoclonus (39.13%) was more common in boys.

Conclusions:

The symptoms of FMD have great impact on the mental health, social, and academic functioning of children. It is important to identify the precipitating factors and associated psychiatric comorbidities in these children as prompt alleviation of these factors by engaging parents and the child psychiatrist will yield better outcomes.

Functional neurological movements in children: Management with a psychological approach

AIM

To develop a cognitive behavioural treatment (CBT) approach that included novel attention training components to support symptom management in children with a primary diagnosis of Functional Movement Disorder (FMD).

METHOD

Eighteen children (9 male and 9 female) with a mean age of 13 years (sd = 2.46, range 10-18 years) were assessed and completed CBT with novel attention training components. Treatment outcomes were measured using the Child Global Assessment Scale (CGAS) which was administered at baseline and post-treatment.

RESULTS

Scores on the CGAS improved significantly post-treatment (p < 0.001) with all participants showing significant change in functioning on the basis of the Reliable Change Index (RCI), with clinically significant change across classification boundaries.

INTERPRETATION

This case series provides support for the use of CBT with attention training components for the management of FMD. Larger trials are necessary to identify which individual treatment components are most effective and to better understand and quantify response to treatment. Future clinical treatment studies would benefit from the inclusion of objective measures of interoception and attentional focus.

Gender Differences in Functional Movement Disorders

Background

Functional neurological disorders are generally more common in females than males, but the reason for this gender difference is not well understood.

Objectives

In this study, we aim to compare the clinical and demographic features of functional movement disorders (FMDs) between males and females.

Methods

We examined clinical data and video-recordings of patients with FMDs evaluated at the Baylor College of Medicine Movement Disorders Clinic.

Results

Of the 196 patients with FMDs, males represented only 30% (n = 59) of the entire cohort. Men had an older age at onset: 40.5 versus 34.1 years (P = 0.026) and an older age at evaluation: 43.8 versus 38.1 years (P = 0.041) compared to women. Functional dystonia was more frequently observed in women: 47.5 versus 20.3% (P < 0.001), but there was a trend for higher frequency of functional gait disorder in men: 44 versus 30% (P = 0.056). Females were particularly over-represented (73.7%) in children and adolescents; but the genders were equally represented in patients aged ≥50 years.

Conclusions

Female patients are over-represented in FMDs, except in individuals aged ≥50 years. Compared to female patients, males with FMDs present later in life and are less likely to have functional dystonia.

Functional Movement Disorders in Elderly

Background

Functional movement disorders (FMDs) have been rarely described in the elderly population.

Methods

This is a retrospective chart review of elderly patients with FMDs (onset >60 years) attending the movement disorders clinic at a tertiary care teaching institute in India.

Results

Out of 117 patients diagnosed with FMD at our center, 18 patients had an onset after the age of 60 years. The male-to-female ratio was 10:8 and the duration of symptoms ranged from 1 day to 5 years. Social (10/18) and physical factors (5/18) with an evident temporal relationship with the onset of FMD were identified in 15 out of 18 patients. Six of them had a past history of depression, anxiety, or other psychiatric illnesses. The tremor was the most frequent phenomenology seen in 11 (61.1%) patients, followed by dystonia in seven (38.8%), choreoballism and tics in two each, and hemifacial spasm and functional gait in one each. Seven patients had more than one phenotype.

Discussion

Tremor was the most frequent movement disorder seen in our patients with FMD. Surprisingly, tics (n = 2) and choreoballistic (n = 2) movements were also found in our patients with FMD, which has not been reported previously in an elderly population. Both physical and social factors were identified preceding the development of FMDs in majority of our patients.

Psychogenic movement disorders in children and adolescents: an update

This short communication provides an update on childhood psychogenic movement disorders (PMD), focusing on descriptive studies and case reports from 2008 to 2018. Known also as functional movement/motor disorders, PMD diagnoses are relatively common in adults but less so in children. In group studies over the past decade, sample prevalence of childhood PMD ranged from 2.8 to 23.1%, with a higher percentage of girls in most studies (consistent with adult PMD literature). Common types of PMD included tremor (32.4%), dystonia (29.5%), and myoclonus (24.3%). Precipitating events for PMD onset included H1N1 influenza vaccinations, family/child stressors, anxiety/depression in the child or parent, panic attacks, behavior disorders, injury or accident, sexual abuse of the child or family member, death of a close relative, parental discord, domestic violence, school-related problems, medical illness/surgery, sleep disturbance, and participation in competitive sport or dance. The most frequently mentioned treatments were cognitive behavioral therapy, psychotherapy, relaxation techniques, and physiotherapy.Conclusion: Although additional cases of childhood PMD have been published over the past decade, little new information has appeared. There is still no "diagnostic gold standard," making an accurate estimate of prevalence virtually impossible and contributing to confusion among pediatricians when trying to identify children with PMD. What is Known: • Psychogenic movement disorders (PMD) occur in children as well as adults. • The most common types of childhood PMD are tremor, dystonia, and myoclonus. What is New: • The most common childhood PMD treatments were cognitive behavioral therapy, psychotherapy, physiotherapy, and relaxation techniques (2008-2018). • Due to lack of a standardized definition for PMD, confusion exists as to which movement disorders to include. With the inability to reliably diagnose PMD and the ambiguity as to which movement disorders it comprises, it is difficult to determine the most effective treatments.

Tremors: Essential Tremor and Beyond

Tremor is a fairly common movement disorder presenting to an outpatient pediatric neurology practice. Tremors can be primary or secondary to underlying neurologic or systemic diseases. When assessing a child with tremor, it is paramount to evaluate the phenomenology of the tremor, determine the presence or absence of other neurologic signs and symptoms, and the possible modifying influence of medications. Proper classification is essential for specific diagnosis and prompt adequate management. Treatment considerations should take into account objective assessment of tremor severity and the degree of disability or impairment experienced by the child. Overall effectiveness of pharmacologic treatments of tremor is unfortunately disappointing. In this article we review the clinical examination, classification, and diagnosis of tremor. The pathophysiology of the different forms of tremor is outlined, and treatment options are discussed.

Psychogenic Movement Disorders in Adults and Children: A Clinical and Video Profile of 58 Indian Patients

Background

Psychogenic movement disorders (PMDs) represent 2% to 20% of patients with movement disorders. There is a paucity of literature on PMD in children, with most existing literature relating to adults only.

Methods

For this detailed report of 58 patients (33 adults and 25 children) with PMD, history was assessed in the form of disease onset, duration, precipitating factors, diagnosis, and outcome. Movement phenotype was classified in terms of its appearance as tremor, dystonia, myoclonus, chorea, and others. Clinical evaluations were done to document variability, distractibility, and entrainment. Surface electromyography studies were obtained in patients with tremor.

Results

Seven adults and 7 children were classified with "documented" PMD, and 26 adults and 18 children were classified with "clinically established" PMD. Abrupt onset was common in adults (75.75%) and children (68%). The most common precipitating factors were family and social issues (42.42%) in adults and fear of examination (40%) and school-related issues (24%) in children. Tremor was the most common PMD in both adults and children. The second most common PMD was hemifacial spasm in adults.

Conclusion

The majority of patients had abrupt onset of symptoms, and tremor was the most common form of movement disorder. The second most common PMDs were hemifacial spasm in adults and dystonia and gait abnormality in children. The most common precipitating factors in adults were related to family and social issues; whereas, in children, examination and school-related issues were most common. Complete improvement was seen in only 405 of patients.

Chiropractic Care of a 10-Year-Old Boy With Nonorganic Gait Disorder: A Case Report

OBJECTIVE

The purpose of this case report is to describe the multidisciplinary management of a boy with nonorganic gait disorder.

CLINICAL FEATURES

A 10-year-old boy presented to a chiropractic clinic having had a concussion 1 week prior. He presented with lower limb muscle weakness and ataxia while weight bearing. He was referred immediately to the emergency department, from which he was sent to a neurologist at a children's hospital. The neurologist's diagnosis was nonorganic gait disorder.

INTERVENTION/OUTCOME

Treatment consisted of physiotherapy, occupational therapy, and a psychiatric assessment. Chiropractic care including manipulative therapy was initiated 6 months after diagnosis. After 1 year, the gait disorder was resolved.

CONCLUSION

The addition of chiropractic care to conventional treatment may have been supportive in the recovery process for this patient. The condition required 1 year to resolve, with questions remaining as to whether the symptom resolution was a result of treatment or natural history.

Gender and Age Determinants of Psychogenic Movement Disorders: A Clinical Profile of 73 Patients

BACKGROUND

Psychogenic movement disorders (PMD) is a group of disorders that cannot be attributed to any structural or biochemical abnormality, but has an underlying psychiatric illness. The profile of PMD varies according to country and socioeconomic factors.

METHODS

The present study reports the clinical profile of patients with PMD from India. Seventy-three patients with documented or clinically established PMD were seen over a period of 14 years with detailed neurological and psychiatric examinations.

RESULTS

The mean age at presentation was 29.1±15.1 years (women, 51%). Approximately 30% were ≤18 years of age (boys, 63.6%). The onset of symptoms was abrupt in 61.6% and the initial body part most often affected was right upper limb (adults, 29.4%; children, 31.8%). Tremor was observed in 31.4% of adults and 9% of children, whereas myoclonus was more common in children (36.4%). Tremors were more often seen in women (42.3%) than in men (20%), whereas myoclonus was almost equally prevalent in girls (37.5%) and boys (35.7%). Depression was the most common psychiatric comorbidity (men, 16%; women, 15.4%). About 42.5% required hospital admission and 57.5% had significant reduction or complete cessation of PMD after counseling, antidepressants, and/ or placebo.

CONCLUSIONS

PMD was equally prevalent among women and men. Tremor was most often observed in adults, whereas myoclonus was most often observed in children. Electrophysiology and placebo were useful supplementary tools for diagnosing PMD.

Functional jerks, tics, and paroxysmal movement disorders

Functional jerks are among the most common functional movement disorders. The diagnosis of functional jerks is mainly based on neurologic examination revealing specific positive clinical signs. Differentiation from other jerky movements, such as tics, organic myoclonus, and primary paroxysmal dyskinesias, can be difficult. In support of a functional jerk are: acute onset in adulthood, precipitation by a physical event, variable, complex, and inconsistent phenomenology, suggestibility, distractibility, entrainment and a Bereitschaftspotential preceding the movement. Although functional jerks and tics share many similarities, characteristics differentiating tics from functional jerks are: urge preceding the tic, childhood onset, rostrocaudal development of the symptoms, a positive family history of tics, attention-deficit hyperactivity disorder or obsessive-compulsive symptoms, and response to dopamine antagonist medication. To differentiate functional jerks from organic myoclonus, localization of the movements can give direction. Further features in support of organic myoclonus include: insidious onset, simple and consistent phenomenology, and response to benzodiazepines or antiepileptic medication. Primary paroxysmal dyskinesias and functional jerks share a paroxysmal nature. Leading in the differentiation between the two are: a positive family history, in combination with video recordings revealing a consistent symptom pattern in primary paroxysmal dyskinesias. In this chapter functional jerks and their differential diagnoses will be discussed in terms of epidemiology, symptom characteristics, disease course, psychopathology, and supportive neurophysiologic tests.

An update on functional (psychogenic) tremor

Functional tremor accounts for at least 50% of patients with functional movement disorders. The diagnostic work-up of these patients can be challenging. It is a multistep process based on patients’ history and clinical criteria finally providing a ‘positive’ diagnosis. Variability of the tremor over the disease course and during clinical examination is characteristic. Patients often show increased attention toward the tremulous body part and distractability of the tremor once attention is drawn away. Sometimes distractability becomes obvious during history taking or neurological examination, in others certain distraction tasks are needed. If uncertainty remains, ancillary investigations such as electrophysiological tests may be helpful. Recent studies suggested that a loss of sense of control of ones actions may help to explain why patients with functional tremor report that they do not experience the abnormal movement as voluntary. Treatment has to be placed in a multidisciplinary team involving neurologists, psychiatrists, physiotherapists and psychologists.

Abnormal movements in children with migraine

The cause and treatment of functional movement disorders and nonepileptic spells in children is poorly understood, and an association with migraine has not previously been reported. We retrospectively reviewed children diagnosed with chronic or episodic migraine at our institution from 2006 to 2013 to determine the proportion with nonorganic movement disorders, their phenomenology, provoking factors, and natural history. Thirty-two patients were identified, representing 4.3% of patients with chronic migraine and 0.9% of patients with episodic migraine. Twenty-four of the 32 (75%) had chronic migraine, whereas 8 (25%) had episodic migraine. Nonepileptic spells was the most common phenomenon in both cohorts, followed by tremor and functional gait disorders. Severe migraine attacks preceded these movements in the majority of patients. With appropriate migraine therapy, significant reduction or resolution of these movements was reported. We conclude that nonorganic movement disorders are observed in pediatric migraine, are more prevalent among chronic migraineurs, and can resolve with improved pain control.

Recognizing uncommon presentations of psychogenic (functional) movement disorders

BACKGROUND

Psychogenic or functional movement disorders (PMDs) pose a challenge in clinical diagnosis. There are several clues, including sudden onset, incongruous symptoms, distractibility, suggestibility, entrainment of symptoms, and lack of response to otherwise effective pharmacological therapies, that help identify the most common psychogenic movements such as tremor, dystonia, and myoclonus.

METHODS

In this manuscript, we review the frequency, distinct clinical features, functional imaging, and neurophysiological tests that can help in the diagnosis of uncommon presentations of PMDs, such as psychogenic parkinsonism, tics, and chorea; facial, palatal, and ocular movements are also reviewed. In addition, we discuss PMDs at the extremes of age and mass psychogenic illness.

RESULTS

Psychogenic parkinsonism (PP) is observed in less than 10% of the case series about PMDs, with a female-male ratio of roughly 1:1. Lack of amplitude decrement in repetitive movements and of cogwheel rigidity help to differentiate PP from true parkinsonism. Dopamine transporter imaging with photon emission tomography can also help in the diagnostic process. Psychogenic movements resembling tics are reported in about 5% of PMD patients. Lack of transient suppressibility of abnormal movements helps to differentiate them from organic tics. Psychogenic facial movements can present with hemifacial spasm, blepharospasm, and other movements. Some patients with essential palatal tremor have been shown to be psychogenic. Convergence ocular spasm has demonstrated a high specificity for psychogenic movements. PMDs can also present in the context of mass psychogenic illness or at the extremes of age.

DISCUSSION

Clinical features and ancillary studies are helpful in the diagnosis of patients with uncommon presentations of psychogenic movement disorders.

Psychogenic movement disorders

PURPOSE OF REVIEW

This review describes the main clinical features of psychogenic (functional) movement disorders and reports recent advances in diagnosis, pathophysiology, and treatment.

RECENT FINDINGS

The terminology and definition of patients with psychogenic movement disorders remain subjects of controversy; the term "functional" has been used more frequently in the literature in recent years regarding the neurobiological substrate underpinning these disorders. Correct diagnosis of psychogenic movement disorders should rely not on the exclusion of organic disorders or the sole presence of psychological factors but on the observation or elicitation of clinical features related to the specific movement disorder (ie, a positive or inclusionary rather than exclusionary diagnosis). Sudden onset, spontaneous remissions, and variability over time or during clinical examination are useful "red flags" suggestive of a psychogenic movement disorder. Imaging studies have demonstrated impaired connectivity between limbic and motor areas involved in movement programming and hypoactivity of a brain region that compares expected data with actual sensory data occurring during voluntary movement. Treatment of psychogenic movement disorders begins with ensuring the patient's acceptance of the diagnosis during the initial debriefing and includes nonpharmacologic (cognitive-behavioral therapy, physiotherapy) and pharmacologic options.

SUMMARY

Psychogenic movement disorders represent a challenging disorder for neurologists to diagnose and treat. Recent advances have increased understanding of the neurobiological mechanism of psychogenic movement disorders. Treatment with cognitive strategies and physical rehabilitation can benefit some patients. As short duration of disease correlates with better prognosis, early diagnosis and initiation of treatment are critical.

The Phenomenology of Functional (Psychogenic) Dystonia

From the very first descriptions of dystonia, there has been a lack of agreement on the differentiation of organic from functional (psychogenic) dystonia. This lack of agreement has had a significant effect on patients over the years, most particularly in the lack of access to appropriate management, whether for those with organic dystonia diagnosed as having a functional cause or vice versa. However, clinico-genetic advances have led to greater certainty about the phenomenology of organic dystonia and therefore recognition of atypical forms. The diagnosis of functional dystonia rests on recognition of its phenomenology and should not be, as far as possible, a diagnosis of exclusion. Here, we present an overview of the phenomenology of functional dystonia, concentrating on the three main phenotypic presentations: functional cranial dystonia; functional fixed dystonia; and functional paroxysmal dystonia. We hope that this review of phenomenology will aid in the positive diagnosis of functional dystonia and, through this, will lead to more rapid access to appropriate management.

Psychogenic paroxysmal movement disorders--clinical features and diagnostic clues

BACKGROUND

The diagnosis of psychogenic paroxysmal movement disorders (PPMD) can be challenging, in particular their distinction from the primary paroxysmal dyskinesias (PxD) remains difficult.

METHODS

Here we present a large series of 26 PPMD cases, describe their characteristics, contrast them with primary PxD and focus on their distinguishing diagnostic features.

RESULTS

Mean age at onset was 38.6 years, i.e. much later than primary PxD. Women were predominantly affected (73%). Most subjects (88.4%) had long attacks, and unlike primary PxD there was a very high within-subject variability for attack phenomenology, duration and frequency. Dystonia was the most common single movement disorder presentation, but 69.2% of the patients had mixed or complex PxD. In 50% of PPMD cases attack triggers could be identified but these were unusual for primary PxD. 42.3% of patients employed unusual strategies to alleviate or stop the attacks. Response to typical medication used for primary PxD was poor. Precipitation of the disorder due to physical or emotional life events and stressors were documented in 57.6% and 65.3% of the cases respectively. Additional interictal psychogenic signs were documented in 34.6% and further medically unexplained somatic symptoms were present in 50% of the cases. 19.2% of patients had a comorbid organic movement disorder and 26.9% had pre-existing psychiatric comorbidities.

CONCLUSION

Although the phenotypic presentation of PPMD can be highly diverse, certain clinical characteristics help in distinguishing this condition from the primary forms of PxD. Recognition is important as multidisciplinary treatment approaches led to significant improvement in most cases.