Spontaneous remissions in spasmodic torticollis

The natural course of idiopathic cervical dystonia

Idiopathic cervical dystonia (ICD) is by far the largest subgroup of dystonia. Still, its natural course is largely unknown. We studied the natural course of 100 ICD patients from our botulinum toxin clinics (age at ICD onset 45.8 ± 13.5 years, female/male ratio 2.0) over a period of 17.5 ± 11.5 years with follow-ups during botulinum toxin therapy and with semi-structured interviews. Two courses of ICD could be distinguished by symptom development of more or less than 6 months. ICD-type 2 was less frequent (19% vs 81%, p < 0.001), had a more rapid onset (8.7 ± 8.0 weeks vs 3.8 ± 3.5 years), a higher remission rate (92% vs 5%, p < 0.001) and a higher prevalence of excessive psychological stress preceding ICD (63% vs 1%, p < 0.001). In both ICD-types, the plateau phase was non-progressive. Significant differences in patient age at ICD onset, latency and extent of remission, female/male ratio and prevalence of family history of dystonia could not be detected. ICD is a non-progressive disorder. ICD-type 1 represents the standard course. ICD-type 2 features rapid onset, preceding excessive psychological stress and a high remission rate. These findings will improve prognosis, treatment strategies and understanding of underlying disease mechanisms. They contradict the widespread fear of patients of a constant and continued decline of their condition. Excessive psychological stress may be an epigenetic factor triggering the manifestation of genetically predetermined dystonia.

Oromandibular Dystonia: A Clinical Examination of 2,020 Cases

Objective: The goal of this study is to better characterize the phenotypic heterogeneity of oromandibular dystonia (OMD) for the purpose of facilitating early diagnosis. Methods: First, we provide a comprehensive summary of the literature encompassing 1,121 cases. Next, we describe the clinical features of 727 OMD subjects enrolled by the Dystonia Coalition (DC), an international multicenter cohort. Finally, we summarize clinical features and treatment outcomes from cross-sectional analysis of 172 OMD subjects from two expert centers. Results: In all cohorts, typical age at onset was in the 50s and 70% of cases were female. The Dystonia Coalition cohort revealed perioral musculature was involved most commonly (85%), followed by jaw (61%) and tongue (17%). OMD more commonly appeared as part of a segmental dystonia (43%), and less commonly focal (39%) or generalized (10%). OMD was found to be associated with impaired quality of life, independent of disease severity. On average, social anxiety (LSA score: 33 ± 28) was more common than depression (BDI II score: 9.7 ± 7.8). In the expert center cohorts, botulinum toxin injections improved symptom severity by more than 50% in ~80% of subjects, regardless of etiology. Conclusions: This comprehensive description of OMD cases has revealed novel insights into the most common OMD phenotypes, pattern of dystonia distribution, associated psychiatric disturbances, and effect on QoL. We hope these findings will improve clinical recognition to aid in timely diagnosis and inform treatment strategies.

Remission in dystonia - Systematic review of the literature and meta-analysis

In isolated, sporadic dystonia, it has been occasionally reported that some patients might undergo symptom remission. However, the exact clinical characteristics of patients with remission remain understudied. Given the important prognostic and pathophysiological implications of dystonic remission, we here provide a systematic review of the literature and a meta-analysis to assess demographic and clinical features associated with this phenomenon. We also provide a list of operational criteria to better define dystonic remission. Using PubMed and Embase, we conducted a systematic literature search in March 2018. 626 records were screened, 31 studies comprising data of 2551 cases with reports predominantly from patients with cervical dystonia (n = 1319) or blepharospasm/Meige syndrome (n = 704) were included in qualitative analysis. Five studies reporting remission in cervical dystonia were eligible for meta-analysis. Complete remission was reported in 11.8% and partial remission for 4.4% of cases. Remission rates were higher in cervical dystonia than in blepharospasm/Meige (e.g. complete remission 15.4% vs. 5.8% respectively). Remission occurred on average 4.5 years after onset of dystonic symptoms. However, the majority of patients (63.8%) relapsed. Meta-analysis for cervical dystonia showed that patients with remission were significantly younger at symptom onset than patients without remission (mean difference -7.13 years [95% CI: 10.58, -3.68], p < 0.0001). Based on our findings, we propose that the degree, the conditions associated with the onset, and the duration of remission are key factors to be considered in a unifying definition of dystonic remission.

Functional dystonia and the borderland between neurology and psychiatry: New concepts

Mind-brain dualism has dominated historical commentary on dystonia, a dichotomous approach that has left our conceptual grasp of it stubbornly incomplete. This is particularly true of functional dystonia, most diagnostically challenging of all functional movement disorders, in which the question of inherent psychogenicity remains a focus of debate. Phenomenological signs considered in isolation lack the specificity to distinguish organic and nonorganic forms, and dystonia's variability has frustrated attempts to develop objective laboratory-supported standards. Diagnostic criteria for functional dystonia that place emphasis on psychiatric symptoms perform poorly in studies of reliability, partly explained by the high frequency of psychopathology in organic dystonia. Novel approaches from the cognitive neurosciences may offer a way forward. Theory on Bayesian statistical prediction in cognitive processing is supported by sufficient experimental evidence for this model to be taken seriously as a way of reconciling contradictory notions about voluntary and unconscious motor control in functional movement disorders. In a Bayesian formulation of functional dystonia, misallocation of attention and abnormal predictive beliefs generate movements that are executed without a sense of agency. Building on this framework, there is a consensus that a biopsychosocial approach is required and that a unified philosophy of brain and mind is the best way to locate dystonia in the neurology-psychiatry borderland. At a practical level, movement disorder neurologists are best placed to differentiate organic from functional dystonia. The main role of psychiatrists is in the diagnosis and management of the primarily psychiatric disorders that often accompany dystonia. © 2016 International Parkinson and Movement Disorder Society.

Head Tremor in Cervical Dystonia

Objective:

To compare the clinical characteristics, natural history, and therapeutic outcome of patients with cervical dystonia (CD) with head tremor (HT+) and without head tremor (HT-).

Methods:

We prospectively evaluated 114 consecutive patients of CD over a 9-month period with a detailed questionnaire. Chi-square and t-tests were employed for statistical analysis.

Results:

Seventy-eight (68.4%) patients had head tremor and 27 of them (34.6%) had tremor as one of the first symptoms. Age at onset of symptoms were similar in HT+ and HT- groups; however there was a higher prevalence in women in the former group (66.7% vs. 41.7%; p=0.01). HT+ patients had more frequent positive family history of essential-like hand/head tremor (21.8% vs. 5.5%; p<0.05), associated neck pain (92.3% vs. 77.8%; p<0.05), and essential-like hand tremor (40% vs. 8.3%; p<0.001). They also appeared to have more frequent history of preceding head/neck trauma (14.1% vs. 8.3%), frequent head rotation (88.5% vs. 69.4%) and antecollis (12.8% vs. 5.5%) but less often head tilt (37.2% vs. 47.2%) and gestes antagonistes (60.2% vs. 75%) than the HT- patients; however these differences were not statistically significant. The frequency of prior psychiatric illnesses, the incidence of dystonias in other parts of the body, frequency of retrocollis and shoulder elevation, and spontaneous remission were similar in the two groups.

Conclusions:

Head tremor is common in CD and is more commonly associated with hand tremor and family history of tremor or other movement disorders. This supports a possible genetic association between CD and essential tremor (ET). Linkage studies are required to evaluate the genetic association between CD and ET.

A Retrospective, Single-Center Comparative Cost Analysis of OnabotulinumtoxinA and AbobotulinumtoxinA for Cervical Dystonia Treatment

BACKGROUND

Chemodenervation with botulinum neurotoxin (BoNT) is recommended as first-line treatment for the management of cervical dystonia. The choice of BoNT for treatment is subject to the consideration of several factors, including cost.

OBJECTIVE

To compare the costs incurred by patients and payers for onabotulinumtoxinA (ONA) or abobotulinumtoxinA (ABO) for the treatment of cervical dystonia.

METHODS

We conducted a retrospective, noninterventional closed cohort study of cervical dystonia patients within a single U.S. private neurological practice. Patient and payer incurred costs from medical billing records for patients satisfying inclusion and exclusion criteria treated from November 1, 2009, through January 1, 2013, were de-identified and included in the analysis. Forty-seven patients initially treated with at least 3 consecutive cycles of ONA, followed by at least 3 consecutive cycles of ABO were included, representing 282 injection cycles available for analysis. Patients were required to have had a positive response to treatment with both agents and no concomitant treatment with BoNT for any other condition during the analysis period. The analysis compared the primary endpoint of median overall payer and patient incurred costs reimbursed to the clinic under each treatment regimen. For the purposes of this cost analysis, comparable clinical outcomes on both therapies was assumed.  

RESULTS

Switching from ONA to ABO resulted in an overall incurred reimbursement cost savings for payers and patients. Median costs per injection cycle for ONA were $1,925 ($0-$2,814) compared with $1,214 ($229-$2,899; P  less than  0.0001) for ABO, representing an approximate 37% reduction in incurred reimbursement costs inclusive of toxin and procedure. Overall toxin reimbursement costs, patient out-of-pocket toxin costs, and the cost of unavoidable waste were also lower when patients were treated with ABO. 

CONCLUSIONS

For patients treated for cervical dystonia, switching from ONA to ABO resulted in payer and patient reimbursement cost reductions in a single U.S. private practice with outcomes assumed to be similar.

Impact of Cervical Dystonia on Work Productivity: An Analysis From a Patient Registry

BACKGROUND

Cervical dystonia is thought to result in high disease burden, but limited information exists on its impact on employment and work productivity. We utilized data from the Cervical Dystonia Patient Registry for the Observation of OnabotulinumtoxinA Efficacy (ClinicalTrials.gov identifier: NCT00836017) to assess the impact of cervical dystonia on employment and work productivity and examine the effect of onabotulinumtoxinA treatments on work productivity.

METHODS

Subjects completed a questionnaire on employment status and work productivity at baseline and final visit. Baseline data were examined by severity of cervical dystonia, predominant subtype, presence of pain, prior exposure to botulinum toxin, and/or utility of a sensory trick. Work productivity results at baseline and final visit were compared in subjects who were toxin-naïve at baseline and received three onabotulinumtoxinA treatments.

RESULTS

Of 1,038 subjects, 42.8% were employed full- or part-time, 6.1% unemployed, 32.7% retired, and 11.8% disabled. Of those currently employed, cervical dystonia affected work status of 26.0%, caused 29.8% to miss work in the past month (mean, 5.1 ± 6.4 days), and 57.8% reported decreased productivity. Half of those unemployed were employed when symptoms began, and 38.5% attributed lost employment to cervical dystonia. Pain, increasing severity, and anterocollis/retrocollis had the largest effects on work status/productivity. Preliminary analyses showed that absenteeism and presenteeism were significantly decreased following onabotulinumtoxinA treatments in the subpopulation that was toxin-naïve at baseline.

CONCLUSIONS

This analysis confirms the substantial negative impact of cervical dystonia on employment, with cervical dystonia-associated pain being a particularly important driver. OnabotulinumtoxinA treatment appears to improve work productivity.

Neural correlates of abnormal sensory discrimination in laryngeal dystonia

Aberrant sensory processing plays a fundamental role in the pathophysiology of dystonia; however, its underpinning neural mechanisms in relation to dystonia phenotype and genotype remain unclear. We examined temporal and spatial discrimination thresholds in patients with isolated laryngeal form of dystonia (LD), who exhibited different clinical phenotypes (adductor vs. abductor forms) and potentially different genotypes (sporadic vs. familial forms). We correlated our behavioral findings with the brain gray matter volume and functional activity during resting and symptomatic speech production. We found that temporal but not spatial discrimination was significantly altered across all forms of LD, with higher frequency of abnormalities seen in familial than sporadic patients. Common neural correlates of abnormal temporal discrimination across all forms were found with structural and functional changes in the middle frontal and primary somatosensory cortices. In addition, patients with familial LD had greater cerebellar involvement in processing of altered temporal discrimination, whereas sporadic LD patients had greater recruitment of the putamen and sensorimotor cortex. Based on the clinical phenotype, adductor form-specific correlations between abnormal discrimination and brain changes were found in the frontal cortex, whereas abductor form-specific correlations were observed in the cerebellum and putamen. Our behavioral and neuroimaging findings outline the relationship of abnormal sensory discrimination with the phenotype and genotype of isolated LD, suggesting the presence of potentially divergent pathophysiological pathways underlying different manifestations of this disorder.

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Abnormal temporal but not spatial discrimination is an LD mediational endophenotype.

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Penetrance of abnormal TDT is higher in familial than sporadic LD.

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No differences in penetrance between clinical phenotypes of LD

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Distinct neural phenotype/genotype relations of TDT reflect divergent pathophysiology.

The Dystonias

Dystonia is a difficult problem for both the clinician and the scientist. It is sufficiently common to be seen by almost all physicians, yet uncommon enough to prevent any physician from gaining broad experience in its diagnosis and treatment. Each case represents a difficult challenge even to the specialist. The basic scientist is faced with investigating a disorder that is without relevant animal models and which is so rare that obtaining suitable tissue for study is a major obstacle. Dystonia may be idiopathic, or associated with lesions from many sources, including a variety of rare diseases. If idiopathic, it may be genetically transmitted or sporadic. If genetically transmitted, it may be generalized or focal, with symptoms varying in different members of the same family. It may be refractory to treatment, or it may respond to any one of a number of individual drugs that have very different mechanisms of action. For idiopathic dystonias, no clear method of genetic transmission has been established and no consistent pathology identified.

Clinical Characteristics and Response to Long-Term Botulinum Toxin Type A Therapy in Patients with Cervical Dystonia at a Neurology Clinic

INTRODUCTION

To determine the demographic and clinical characteristics and response to botulinum toxin type A (BoNT-A) therapy in patients with cervical dystonia (CD).

METHOD

A retrospective analysis of the detailed medical records of the patients with CD, followed up at our Botulinum Toxin Outpatient Clinic from 1998 to 2012, was performed. The treatment data were compared between the patients with primary CD and those with secondary CD; between patients receiving BoNT-A treatment for more than 5 years and less than five years, and between first applications and last applications.

RESULTS

Fifty-seven patients (56.15% women) with CD were included in this study. The mean age was 41.01±13.42 years, the mean age at symptom onset was 32.93±15.45 years, and the mean dystonia duration was 8.10±8.5 years. The interval between onset of symptom and first BoNT-A treatment was 5.94±9.06 years, the duration of BoNT-A treatment was 36.13±29.17 months, and the number of applications was 8.48±6.23 in 45 patients with CD who were under treatment with BoNT-A for more than 1 year and had received at least three injections before. There was no difference between the patients with primary and secondary CD in terms of treatment results. The injection interval of the patients receiving BoNT-A treatment for more than 5 years and less than 5 years was 18.37±5.10 and 14.43±2.36 weeks, respectively (p=.001). There were no differences in the other treatment values. The mean doses were 559.00±147.60 vs. 681.66±188.09 units (p=.0001), the durations of improvement were 11.82±2.71 vs. 13.00±4.00 weeks (p=.014), the response scores were 2.71±.3 vs. 3.02±.5 (p=.002), the response ratings were 64.66%±16.18 vs. 71.22%±17.29 (p=.001), and the numbers of muscles applied were 3.15±1.16 vs. 3.51±0.99 (p=.012) in the first and last applications, respectively.

CONCLUSION

There were no differences between the response of the patients with primary and secondary CD. Our results showed a statistically significant increase in the mean dose of BoNT-A, the response rating, the number of muscles applied, the duration of improvement, and the injection interval over time.

The phenomenology and natural history of idiopathic lower cranial dystonia

Background

Many patients with lower cranial dystonia (LCrD) are misdiagnosed, and recognition of this condition by general practitioners and dental health professionals is limited.

Methods

We define the phenomenology and natural history of idiopathic LCrD, presenting in 41 patients with the disorder, the largest series of these patients reported to date.

Results

Phenomenology of dystonia included lower cranial and pharyngeal involvement, jaw opening and jaw closing dystonia, and tongue dystonia. Of 25 newly described patients, 72% (18) were female, average age at onset was 56 years, and delay before correct diagnosis was 3.8 years (0-25 years, median 2 years). Eleven patients (44%) reported a precipitating event, the most common of which was recent dental work. Geste antagonistes were found in 18 patients (72%). Response to treatment was mixed, indicating an unmet therapeutic need.

Conclusions

Idiopathic LCrD is often missed and institution of effective therapy is often delayed. The clinical features and natural history of LCrD are similar to other forms of focal dystonia.

Electronic supplementary material

The online version of this article (doi:10.1186/2054-7072-1-3) contains supplementary material, which is available to authorized users.

TOR1A polymorphisms in a Russian cohort with primary focal/segmental dystonia

PURPOSE/AIM OF THE STUDY

To analyze contribution of rs3842225 and rs1182 single nucleotide polymorphisms (SNP) in TOR1A gene, the causative gene for the DYT1 form of hereditary early-onset generalized dystonia, to the development of focal and segmental dystonia in Russian patients.

MATERIALS AND METHODS

We analyzed associations between rs3842225 and rs1182 polymorphisms in TOR1A and focal/segmental dystonia in 254 patients from Russian population, including 218 Slavic patients and 36 patients of mixed ethnic background.

RESULTS

Stratification of patients based on age at the disease onset (≤ 30 years and > 30 years) showed statistically significant prevalence of the del-allele at the rs3842225 locus in Slavic patients with earlier age of onset of dystonia (36.96% vs. 21.39% in patients with late age of onset, p = 0.002) and an overrepresentation of the T-allele at the rs1182 locus (36.96% vs. 21.69%, p = 0.003). In Slavs, we also observed an overrepresentation of the homozygous genotypes, T/T (general sample of dystonia, 9.17% and focal dystonia, 10.28%) or G/G (general sample of dystonia, 60.55% and focal dystonia, 58.86%), compared to controls (T/T, 4.27% and G/G, 55.49%). In non-Slavic patients, we revealed neither significant associations, nor statistical tendencies regarding any of the clinical features.

CONCLUSIONS

Our data in an Eastern Slavic (Russian) population correspond well to results of other studies from different countries and confirm that certain TOR1A genotypes may be regarded as factors predisposing to focal and segmental dystonia.

Genetic animal models of dystonia: common features and diversities

Animal models are pivotal for studies of pathogenesis and treatment of disorders of the central nervous system which in its complexity cannot yet be modeled in vitro or using computer simulations. The choice of a specific model to test novel therapeutic strategies for a human disease should be based on validity of the model for the approach: does the model reflect symptoms, pathogenesis and treatment response present in human patients? In the movement disorder dystonia, prior to the availability of genetically engineered mice, spontaneous mutants were chosen based on expression of dystonic features, including abnormal muscle contraction, movements and postures. Recent discovery of a number of genes and gene products involved in dystonia initiated research on pathogenesis of the disorder, and the creation of novel models based on gene mutations. Here we present a review of current models of dystonia, with a focus on genetic rodent models, which will likely be first choice in the future either for pathophysiological or for preclinical drug testing or both. In order to help selection of a model depending on expression of a specific feature of dystonia, this review is organized by symptoms and current knowledge of pathogenesis of dystonia. We conclude that albeit there is increasing need for research on pathogenesis of the disease and development of improved models, current models do replicate features of dystonia and are useful tools to develop urgently demanded treatment for this debilitating disorder.

Movement disorders associated with spontaneous CSF leaks: A case series

Importance and Objective

Headache is the most common symptom in spontaneous CSF leaks, frequently associated with additional manifestations. Herein, attention is drawn to movement disorder as a notable manifestation of spontaneous CSF leaks.

Design

Four women and one man (ages 51–78 years) with spontaneous CSF leaks and movement disorders were evaluated clinically and by pertinent neuroimaging studies with follow-up of one to seven years (mean 3.2 years).

Results

The movement disorder consisted of choreiform movements in two patients, torticollis in one, mixed tremor in one, and parkinsonism in one. All except the last patient had headaches (orthostatic in one, Valsalva maneuver-induced in one, both orthostatic and Valsalva-induced in two, lingering low-grade headache in one). Diffuse pachymeningeal enhancement and sinking of the brain was noted in all. CT-myelography showed definite CSF leak in three and equivocal leak in one, while no leak could be located in the fifth patient. Two patients improved over time with complete resolution of the movement disorder. One responded to epidural blood patch with complete resolution of his choreiform movements. Two patients required surgery and epidural blood patches. Results were drastic but nondurable in one, while complete recovery was achieved in the other.

Conclusion

Movement disorders are uncommon in spontaneous CSF leaks but occasionally can be one of the major components of the clinical presentation.

Focal task-specific lower extremity dystonia associated with intense repetitive exercise: a case series

BACKGROUND

Focal task-specific dystonia of the lower extremity associated with intense repetitive exercise has recently been recognized. The clinical course, treatment response and prognosis remain poorly understood.

METHODS

Individuals with lower extremity task-specific dystonia evaluated at UCSF's Movement Disorders Center (2004-2012) were eligible for this descriptive case study series if he/she had a history of strenuous and prolonged exercise involving the lower extremity and had no abnormal neurological or medical conditions to explain the involuntary movements. Data was gathered from the medical history and a self-report questionnaire. The findings were compared to 14 cases previously reported in the literature.

RESULTS

Seven cases (4M/3F) were identified with a diverse set of exercise triggers (cycling, hiking, long-distance running, drumming). The mean age of symptom onset was 53.7 ± 6.1 years. The median symptom duration prior to diagnosis was 4 (9.5) years. Several patients underwent unnecessary procedures prior to being appropriately diagnosed. Over a median of 2 (3.5) years, signs and symptoms progressed to impair walking. Seven patients had improvement in gait with treatment (e.g. botulinum toxin injections, benzodiazepines, physical therapy, bracing, body weight supported gait training and/or functional electrical stimulation of the peroneal nerve) and six returned to a reduced intensity exercise routine.

CONCLUSIONS

Isolated lower extremity dystonia associated with strenuous, repetitive exercise is relatively uncommon, but disabling and challenging to treat. The pathophysiology may be similar to task-specific focal dystonias of the upper limb. Prompt recognition of leg dystonia associated with extreme exercise could minimize unnecessary testing and procedures, and facilitate earlier treatment.

Torticollis

Torticollis refers to a twisting of the head and neck caused by a shortened sternocleidomastoid muscle, tipping the head toward the shortened muscle, while rotating the chin in the opposite direction. Torticollis is seen at all ages, from newborns to adults. It can be congenital or postnatally acquired. In this review, we offer a new classification of torticollis, based on its dynamic qualities and pathogenesis. All torticollis can be classified as either nonparoxysmal (nondynamic) or paroxysmal (dynamic). Causes of nonparoxysmal torticollis include congenital muscular; osseous; central nervous system/peripheral nervous system; ocular; and nonmuscular, soft tissue. Causes of paroxysmal torticollis are benign paroxysmal; spasmodic (cervical dystonia); Sandifer syndrome; drugs; increased intracranial pressure; and conversion disorder. The description, epidemiology, clinical presentation, evaluation, treatment, and prognosis of the most clinically significant types of torticollis follow.

Genetic evidence for an association of the TOR1A locus with segmental/focal dystonia

Polymorphisms in the TOR1A/TOR1B region have been implicated as being associated with primary focal and segmental dystonia. In a cohort of subjects with either focal or segmental dystonia affecting the face, larynx, neck, or arm, we report a strong association of a single nucleotide polymorphism (SNP), the deletion allele at the Mtdel SNP (rs3842225), and protection from focal dystonia. In contrast, we did not find an association of either allele at the D216H SNP (rs1801968) with focal or segmental dystonia in the same cohort.

Adult-onset dystonia

Dystonia is defined as involuntary sustained muscle contractions producing twisting or squeezing movements and abnormal postures. The movements can be stereotyped and repetitive and they may vary in speed from rapid to slow; sustained contractions can result in fixed postures. Dystonic disorders are classified into primary and secondary forms. Several types of adult-onset primary dystonia have been identified but all share the characteristic that dystonia (including tremor) is the sole neurologic feature. The forms most commonly seen in neurological practice include cranial dystonia (blepharospasm, oromandibular and lingual dystonia and spasmodic dysphonia), cervical dystonia (also known as spasmodic torticollis) and writer's cramp. These are the disorders that benefit most from botulinum toxin injections. A general characteristic of dystonia is that the movements or postures may occur in relation to specific voluntary actions by the involved muscle groups (such as in writer's cramp). Dystonic contractions may occur in one body segment with movement of another (overflow dystonia). With progression, dystonia often becomes present at rest. Dystonic movements typically worsen with anxiety, heightened emotions, and fatigue, decrease with relaxation, and disappear during sleep. There may be diurnal fluctuations in the dystonia, which manifest as little or no involuntary movement in the morning followed by severe disabling dystonia in the afternoon and evening. Morning improvement (or honeymoon) is seen with several types of dystonia. Patients often discover maneuvers that reduce the dystonia and which involve sensory stimuli such as touching the chin lightly in cervical dystonia. These maneuvers are known as sensory tricks, or gestes antagonistes. This chapter focuses on adult-onset focal dystonias including cranial dystonia, cervical dystonia, and writer's cramp. The chapter begins with a review of the epidemiology of focal dystonias, followed by discussions of each major type of focal dystonia, covering clinical phenomenology, differential genetics, and diagnosis. The chapter concludes with discussions of the pathophysiology, the few pathological cases published of adult-onset focal dystonia and management options, and a a brief look at the future.

Therapeutic challenges in dystonia

Because dystonia can vary in clinical presentation and etiology, proper diagnosis and classification of these disorders are important in making therapeutic decisions. In primary dystonia, treatment is generally geared toward alleviating symptoms rather than curing the underlying condition, therefore severity of contractions, pain, and functional and social impact are also factors to consider in determining if and how to initiate therapy. On the other hand, if a secondary cause is identified, then it is often appropriate to direct treatment toward the underlying disorder. Treatment options include physical and occupational therapy, oral medications, botulinum toxin, and surgery. This article briefly reviews the clinical features, pathophysiology, and classification of dystonia before reviewing current therapeutic options.

Cervical dystonia

Cervical dystonia is a common disorder with significant associated morbidity. Although limited benefit can be derived from oral pharmacologic agents, the advent of botulinum neurotoxin (BoNT) injection has provided a valuable tool in the treatment of this disorder. In order to provide effective treatment, the physician must have an intimate knowledge of the anatomy and function of the neck musculature. Novel BoNT formulations, even of the same serotype, are not equivalent and thus require careful dose titration. Formulation improvements may result in reduced immunoresistance. In patients labeled as treatment resistant to BoNT, careful electromyographic reassessment of select muscles for injection will frequently result in improved clinical benefit.

Retrocollis, anterocollis or head tremor may predict the spreading of dystonic movements in primary cervical dystonia

BACKGROUND AND PURPOSE: Few studies have attempted to develop clinical predictors for cervical dystonia (CD) aiming at progression of the dystonic movement. METHOD: We retrospectively evaluated 73 patients with primary CD who underwent treatment with Botulinum toxin type-A (BTX-A). The patients were assembled in two groups according to the spread of dystonia during follow-up: spreading and non-spreading CD. We performed a binary logistic regression model using spreading of cervical dystonia as dependent variable aiming to find covariates which increase the risk of spreading. RESULTS: Our logistic regression model found the following covariates and their respective risk ratios: time of disease >18.5 months=2.4, retrocollis=1.9, anterocollis=1.8, head tremor=1.6. CONCLUSION: Time of disease >18.5 months, retrocollis, anterocollis and head tremor may predict spreading of dystonic movement to other regions of the body in CD patients.

Cervical dystonia: clinical and therapeutic features in 85 patients

We studied patients with cervical dystonia (CD) to determine clinical features and response to botulinum toxin A (BoNT/A). Patients were submitted to clinical, laboratory and neuroimaging evaluation. BoNT/A was injected locally in 81 patients using electromyographic guidance. Four patients who had had previous treatment were considered to be in remission. The average ages at onset of focal dystonia and segmental dystonia were greater than for generalized dystonia (p<0.0003). The severity of the abnormal head-neck movements were more severe among the patients with generalized dystonia (p<0.001). Pain in the cervical area was noted in 59 patients. It was not possible to determine the etiology of the disease in 62.3% of patients. Tardive dystonia was the most common secondary etiology. A major improvement in the motor symptoms of CD and pain was observed in patients following treatment with BoNT/A. The tardive dystonia subgroup did not respond to the treatment. Dysphagia was observed in 2.35% of the patients.

Cervical dystonia: disease profile and clinical management

Cervical dystonia, the most common focal dystonia, frequently results in cervical pain and disability as well as impairments affecting postural control. The predominant treatment for cervical dystonia is provided by physicians, and treatment can vary from pharmacological to surgical. Little literature examining more conservative approaches, such as physical therapy, exists. This article reviews the etiology and pathophysiology of the disease as well as medical and physical therapist management for people with cervical dystonia.

Dystonia gravidarum: A new case with a long follow-up

We report a case of cervical dystonia occurring in a 33-year-old without personal history of movement disorder but with family history of essential tremor, primigravid, primiparous woman at 1 weeks' amenorrhea, resolved completely after delivery in the course of 3 months. Dystonia never recurred in the following 5 years. Several neurological disorders are known to occur or worsen during pregnancy. As far as we know, this is the second reported case of dystonia occurring during pregnancy, thus confirming that dystonia gravidarum represents a new entity and should be considered in women of reproductive age affected by dystonia, especially when presenting with rapid-onset cervical dystonia.

The entity of young onset primary cervical dystonia

Primary cervical dystonia is typically an adult onset condition with symptom onset usually in the fifth and sixth decade. Young onset (<28 years) is uncommon. We report 76 patients with cervical dystonia as a presenting or predominant feature, with disease onset before the age of 28. Male to female ratio was 1.24:1 and the mean onset age was 21 (3-28) years. A family history of tremor and/or dystonia was noted in 26.3%. Depression and anxiety attacks were present in 23.7%. Prior injury or surgery involving the neck was noted in 17.1%. 23 (30.3%) experienced spontaneous partial or complete remissions within the first 5 years of onset, but all relapsed. Cervical dystonia was predominantly rotational torticollis. 30% developed extra-nuchal dystonia and tremor affecting contiguous parts but in only one there was spread to affect the legs. All 15 patients tested for the DYT1 gene were negative. 74% responded favorably to botulinum toxin injections, whereas none of the 13 patients treated with L-Dopa preparations had a beneficial response. The distinctive features of this entity are discussed.

My battle with spasmodic torticollis: a healing experience

The life-transforming experience of overcoming spasmodic torticollis compelled the author to write the following personal account. The author, who triumphed over this debilitating disease, is now an advocate of holistic nursing practices that motivate patients through a genuine concern for patient well-being, community, and humanity. The author describes her personal experience of grief and the grieving process; the healing effects of crying; and her selection of the complementary and alternative therapies of prayer, music, and massage that became instrumental in finding a pathway to recovery. The story has appealing implications for strategies that utilize these concepts and techniques in clinical practice.

Dystonia

Dystonia is a disorder of involuntary sustained muscle contractions. It is commonly classified by age of onset, distribution of involved body regions, and etiology. The pathophysiolgy of this condition is complex and imperfectly understood. This article reviews the epidemiology, genetics, clinical features, and approach to diagnosis and treatment of dystonia.

The diagnosis of dystonia

Dystonia is a movement disorder with many presentations and diverse causes. A systematic approach to dystonia helps to ensure that patients with this disorder receive optimum care. This Review begins with a summary of the clinical features of dystonia, followed by a discussion of other disorders to be considered and excluded before assigning the diagnosis of dystonia. Next, we emphasise the importance of classifying dystonia along several dimensions, and we explain how doing so aids in narrowing the differential diagnosis. The more common forms of dystonia are discussed in detail. Finally, we describe how to apply the clinical information for selection of appropriate laboratory investigations.

Psychogenic movement disorders: diagnosis and management

Psychogenic movement disorders (PMDs) are best defined as hyper- or hypo-kinetic movement disorders, often associated with gait disorders, that cannot be directly attributed to a lesion or dysfunction of the nervous system and which are derived in most cases from psychological or psychiatric causes. There are a variety of PMDs including tremor, dystonia, parkinsonism, gait disorders and, even, unusual forms including paroxysmal dyskinesias. As has been recognised in the recent literature, PMDs cannot be strictly classified into clearly defined psychiatric disorders such as somatoform, dissociative or conversion disorders. In this review, we discuss the diagnosis of various PMDs (including hyper- and hypo-kinetic disorders; and current evidence for underlying comorbid disorders) and the current therapeutic approach to them. The therapy of PMDs is not well established, is very challenging to the clinician, and a better outcome can be achieved in the setting of a team approach involving movement disorders specialists, psychiatrists and therapists who specialise in cognitive-behavioural techniques. Current pharmacological and non-pharmacological approaches to treatment focus on therapy of underlying comorbid psychiatric and psychological issues, although compliance is a major concern.

Cervical dystonia mimicking dropped-head syndrome after radiotherapy for laryngeal carcinoma

We report a case of cervical dystonia mimicking dropped-head syndrome (DHS) in a 57-year-old man treated for laryngeal carcinoma by radiotherapy (74.4 Gy) 3 months before. Cervical computerized tomographic scan and magnetic resonance imaging (MRI) did not find any muscle fat changes but found a high-intensity signal on T2 weighted images in the cervical spinal cord. Clinical and electromyographic findings were consistent with cervical dystonia. A trapezius biopsy was normal. Spontaneous remission of the dystonia was observed for 1 month whereas the laryngeal carcinoma progressed. The link between cervical dystonia and radiotherapy might be acute radiation-induced damage to the cervical spinal cord.

Botulinum toxin therapy for cervical dystonia

Botulinum toxin revolutionized the treatment of cervical dystonia. In contrast to systemically active medications, the effect of botulinum toxin results from selective administration to weaken muscles involved in the dystonic posturing of the head. This article reviews the pathophysiologic basis of symptoms in cervical dystonia and how botulinum toxin alleviates them. Other therapeutic options are reviewed for comparison. This article discusses strategies for maximizing the clinical benefit of botulinum toxin in this disorder and reviews muscle selection and identification with electromyography.

Movement disorders

Movement disorders are commonly encountered in clinical practice. The diagnosis of movement disorders relies on a focused history and neurologic examination. Diagnostic steps include (1) identification of the phenomenology of the movements (eg, tremor); (2) characterization of appropriate clinical syndromes; and (3) differential diagnosis of specific disease entities. Accurate diagnosis is essential because symptomatic treatment exists for most movement disorders.

Focal and segmental primary dystonia in north-western Germany--a clinico-genetic study

OBJECTIVES

To determine the frequency of familial focal and segmental dystonias in a large patient cohort with primary dystonia from north-western Germany.

MATERIALS AND METHODS

In this study, 130 patients with focal or segmental dystonia were examined and a family history was obtained. Whenever possible, affected relatives were examined (a total of 789 first-degree relatives). Data on disease duration, age at disease onset and age of the patients were investigated by Student's t-test and a segregation analysis was performed by Weinberg's proband method.

RESULTS

Age at onset of disease was significantly later in the blepharospasm group. Only in the writer's cramp group were women outnumbered by men. A positive family history was found in 15 of the 130 index patients (11.5%). None of 102 index patients tested carried the GAG deletion in the DYT1 gene.

CONCLUSIONS

In accordance with previous series our study provides evidence that primary focal dystonia may have a genetic etiology, most probably caused by an autosomal dominant trait with reduced penetrance.

Selective peripheral denervation for spasmodic torticollis: 13-year experience with 155 patients

OBJECT

Botulinum toxin injections are the best therapeutic option in patients with spasmodic torticollis. Although a small number of patients do not benefit from such therapy, the majority respond well but may develop antibodies to the toxin after repeated applications. In those termed primary nonresponders, no improvement related to botulinum toxin has been shown. In patients in whom no response was shown and those in whom resistance to the therapy developed, selective peripheral denervation is a neurosurgical option.

METHODS

Between June 1988 and August 2001, 155 patients underwent selective peripheral denervation. Surgery was performed at a mean of 8.5 years after the onset of symptoms (range 0.5-37 years). The mean age of the patients at the onset of dystonia was 39.7 years (range 17-77 years). For evaluation of results, patients' responses were assessed. Results were obtained in 140 patients in whom the follow-up period ranged from 3 to 124 months (mean 32.8 months): 18 reported complete relief of their symptoms, 50 significant relief, and 34 moderate relief; 19 noted only minor relief and the remaining 19 no improvement. The results differ substantially when compared with those previously demonstrated in patients who received botulinum toxin injections. Although 80% of the secondary nonresponders were satisfied with the result of surgery, only 62% of the primary nonresponders considered the operation helpful. There were no major side effects. The recurrence rate was 11%.

CONCLUSIONS

The injection of botulinum toxin should be the first-choice treatment. If surgery is required, selective peripheral denervation provides the best results and has the fewest side effects compared with all surgical options.

Cervical dystonia pathophysiology and treatment options

Dystonia is a syndrome of sustained involuntary muscle contractions, frequently causing twisting and repetitive movements or abnormal posturing. Cervical dystonia (CD) is a form of dystonia that involves neck muscles. However, CD is not the only cause of neck rotation. Torticollis may be caused by orthopaedic, musculofibrotic, infectious and other neurological conditions that affect the anatomy of the neck, and structural causes. It is estimated that there are between 60,000 and 90,000 patients with CD in the US. The majority of the patients present with a combination of neck rotation (rotatory torticollis or rotatocollis), flexion (anterocollis), extension (retrocollis), head tilt (laterocollis) or a lateral or sagittal shift. Neck posturing may be either tonic, clonic or tremulous, and may result in permanent and fixed contractures. Sensory tricks ('geste antagonistique') often temporarily ameliorate dystonic movements and postures. Commonly used sensory tricks by patients with CD include touching the chin, back of the head or top of the head. Patients with CD are classified according to aetiology into two groups: primary CD (idiopathic--may be genetic or sporadic) or secondary CD (symptomatic). Patients with primary CD have no evidence by history, physical examination or laboratory studies (except primary dystonia gene) of any secondary cause for the dystonic symptoms. CD is a part of either generalised or focal dystonic syndrome which may have a genetic basis, with an identifiable genetic association. Secondary or symptomatic CD may be caused by central or peripheral trauma, exposure to dopamine receptor antagonists (tardive), neurodegenerative disease, and other conditions associated with abnormal functioning of the basal ganglia. In the majority of patients with CD, the aetiology is not identifiable and the disorder is often classified as primary. Unless the aetiological investigation reveals a specific therapeutic intervention, therapy for CD is symptomatic. It includes supportive therapy and counselling, physical therapy, pharmacotherapy, chemodenervation [botulinum toxin (BTX), phenol, alcohol], and central and peripheral surgical therapy. The most widely used and accepted therapy for CD is local intramuscular injections of BTX-type A. Currently, both BTX type A and type B are commercially available, and type F has undergone testing. Pharmacotherapy, including anticholinergics, dopaminergic depleting and blocking agents, and other muscle relaxants can be used alone or in combination with other therapeutic interventions. Surgery is usually reserved for patients with CD in whom other forms of treatment have failed.

[Psychogenic dystonia: report of 2 cases]

Movement disorders have rarely been the result of psychiatric disturbances. Psychogenic dystonia is caracterized by inconsistent findings, a known precipitant factor, onset in legs, pain, multiple somatizations and incongruent association with other movement disorders. We report two patients with clinically established psychogenic dystonia. Patient 1: a female that presented sudden loss of strength in her four limbs; she developed feet dystonia, alternant laterocollis, generalized and irregular tremor, and limb hypertonia that disappeared with distraction; psychological examination showed severe depression, hypochondria and obsessive disorder. Patient 2: a female that presented with irregular limb tremors that disappeared with distraction and left foot dystonia nine years ago; she gradually lost her walk capacity; she complained pain in lumbar area and in her left limb, psychological examination showed infantile behaviour, low frustration tolerance, impulsivity and self-aggression. Their complementary exams showed no alterations and they had no response to specific pharmacological treatment. Dystonia is rarely psychogenic, but this etiology is suggested when clinical characteristics are inconsistent and incongrous with a classical disorder. It should be part of differential diagnosis when appears in association with other somatization or psychiatric disorders.

Post-traumatic cervical dystonia: a distinct entity?

BACKGROUND/OBJECTIVE

The incidence of head/neck trauma preceding cervical dystonia (CD) has been reported to be 5-21%. There are few reports comparing the clinical characteristics of patients with and without a history of injury. Our aim was to compare the clinical characteristics of idiopathic CD (CD-I) to those with onset precipitated by trauma (CD-T).

METHODS

We evaluated 114 consecutive patients with CD over a 9-month period. All patients were interviewed using a detailed questionnaire and had a neurological examination. Their clinical charts were also reviewed.

RESULTS

Fourteen patients (12%) had mild head/neck injury within a year preceding the onset of CD. Between the two groups (CD-I and CD-T), the gender distribution (F:M of 3:2), family history of movement disorders (32% vs. 29%), the prevalence of gestes antagonistes (65% vs. 64%), and response to botulinum toxin were similar. There were non-specific trends, including an earlier age of onset (mean ages 43.3 vs. 37.6), higher prevalence of neck pain (86% vs. 100%), head tremor (67% vs. 79%), and dystonia in other body parts (23% vs. 36%) in CD-T.

CONCLUSIONS

CD-I and CD-T are clinically similar. Trauma may be a triggering factor in CD but this was only supported by non-significant trends in its earlier age of onset.

Search for a founder mutation in idiopathic focal dystonia from Northern Germany

Both the discovery of the DYT1 gene on chromosome 9q34 in autosomal dominant early-onset torsion dystonia and the detection of linkage for one form of adult-onset focal dystonia to chromosome 18p (DYT7) in a family from northern Germany provide the opportunity to further investigate genetic factors in the focal dystonias. Additionally, reports of linkage disequilibrium between several chromosome 18 markers and focal dystonia, both in sporadic patients from northern Germany and in members of affected families from central Europe suggest the existence of a founder mutation underlying focal dystonia in this population. To evaluate the role of these loci in focal dystonia, we tested 85 patients from northern Germany who had primary focal dystonia, both for the GAG deletion in the DYT1 gene on chromosome 9q34 and for linkage disequilibrium at the chromosome 18p markers D18S1105, D18S1098, D18S481, and D18S54. None of these patients had the GAG deletion in the DYT1 gene. Furthermore, Hardy-Weinberg analysis of markers on 18p in our patient population and in 85 control subjects from the same region did not support linkage disequilibrium. Taken together, these results suggest that most cases of focal dystonia in patients of northern German or central European origin are due neither to the GAG deletion in DYT1 nor to a proposed founder mutation on chromosome 18p but must be caused by other genetic or environmental factors.

Haplotype analysis at the DYT1 locus in Ashkenazi Jewish patients with occupational hand dystonia

Genetic haplotypes at five marker loci that are closely linked to the DYT1 gene on chromosome 9q were determined in 10 Ashkenazi Jewish patients with focal hand dystonia (eight with musician's cramp, two with writer's cramp). The founder haplotype associated with > 90% of cases generalized dystonia in the Ashkenazi Jewish population could not be constructed from any of the twenty chromosomes. Potential haplotypes were determined, and no common haplotype was discerned in these patients. These findings argue against a role for the founder mutation in the DYT1 gene in the etiology of occupational hand dystonia in this ethnic group. Further, if the DYT1 gene is involved in these later onset dystonias, there is no evidence for a common mutation in the Ashkenazic Jewish population. It appears that excessive, repetitive use, possibly in combination with ulnar neuropathy, may serve as the inciting cause of some focal dystonias.

Sex prevalence of focal dystonias

The sex prevalence of idiopathic focal dystonia is reported from a data base review of all patients seen at the National Hospital of Neurology, Queen Square and King's College, London up to 1993. There was a higher prevalence of females to males in all categories of focal dystonia involving the craniocervical region. The female to male ratio for cranial dystonia was 1.92:1 (P < 0.01) and 1.6:1 (P < 0.001) for spasmodic torticollis. On the other hand, twice as many men than women had writer's cramp (M:F = 2.0:1, P < 0.01). At present, there is no clear explanation to account for this differences in the sex prevalence of different types of focal dystonia.

Epidemiology and outcome of cervical dystonia (spasmodic torticollis) in Rochester, Minnesota

The natural history of cervical dystonia (spasmodic torticollis) was investigated in a population-based study in Rochester, Minnesota. Eleven new cases were identified with onset during the 20-year period 1960-1979. The overall incidence rate was 1.2 per 100,000 person-years (95% confidence interval 0.5-1.9) with a female:male ratio of age-adjusted incidence rates of 3.6:1. A unitary etiology was not apparent: injury antedated onset in four of the 11 patients, whereas six had documented thyroid disease and four had diabetes. A family history of movement disorder was recorded for only one subject. Only one of the cases would have been classified as moderate in severity; the others were mild. In follow-up through 1993, progressive disability was noted in only two patients, and two others went into remission. Three cases of intracranial aneurysm were confirmed, two of which produced fatal subarachnoid hemorrahage. A third death was due to amyotrophic lateral sclerosis.

Psychogenic dystonia: a review of 18 cases

OBJECTIVE

To review the clinical characteristics and associated features found in patients with psychogenic dystonia.

METHODS

A 10 year retrospective chart review of all patients diagnosed by the author as having psychogenic dystonia.

RESULTS

Eighteen patients fulfilled diagnostic criteria for "Documented" or "Clinically Established" psychogenic dystonia. Clinical characteristics of the dystonia were inconsistent or incongruous with established forms of organic dystonia. Fourteen of the 18 patients had a known precipitant. In most, the onset was abrupt and progression occurred rapidly, often to fixed dystonic postures. In contrast to idiopathic dystonia, involvement of the legs was common (12 patients), despite onset in adult life. Although cases of isolated paroxysmal dystonia were excluded in the review, 10 patients had paroxysmal worsening of dystonia or other abnormal movements. Pain was a prominent feature in 14 of 16 patients with the complaint and 1 patient with documented psychogenic dystonia also had well established reflex sympathetic dystrophy (RSD). Other psychogenic movement disorders, psychogenic neurological signs and multiple somatizations were common. Long-term follow up was available for less than one-half of the patients. Outcome varied considerably; some patients had complete resolution of symptoms (including 1 who had undergone 2 previous thalamotomies) and others remained disabled by persistent dystonia.

CONCLUSIONS

Dystonia is uncommonly due to primary psychological factors. At times this is an extremely difficult diagnosis to make and even when the diagnosis is confirmed, management remains very challenging. Future studies are required in hopes of providing more efficient means of distinguishing psychogenic dystonia from other dystonic syndromes especially those which rarely follow peripheral injury or accompany RSD/causalgia syndromes.

Spread of symptoms in idiopathic torsion dystonia

We reviewed the histories of 115 patients who had idiopathic dystonia and who were 21 years of age and younger at onset of symptoms and 472 patients with onset older than age 21. Patients with onset in the lower extremities tended to be younger at onset (mean age 8.4 years), have rapid spread of symptoms to other body parts, and to develop generalized dystonia. Patients with onset in the upper extremities tended to be older at onset (mean age 11.2 years) and were less likely to develop generalized dystonia, but were more likely to experience spread of symptoms many years after the disease began. Almost 20% of patients younger than age 22 began with torticollis, and 67% of these remained focal after a mean 14.9 years. In adults, dystonic symptoms remained focal in the majority, but approximately 15-30% of patients presenting with blepharospasm, torticollis, laryngeal or brachial dystonia eventually experienced dystonia outside the initially involved segment. Almost 50% of children and adolescents with dystonia reported a family history of dystonia, compared with approximately 10-13% of patients with torticollis, laryngeal or brachial dystonia. Less than 3% of patients with blepharospasm reported a family history of dystonia. There were only minor differences in the pattern of spread of dystonic symptoms between Jewish and non-Jewish patients. Although younger patients were more likely to report a family history of dystonia, patterns of spread were the same for familial and sporadic patients in the same age range.