Lower limb involvement in adult-onset primary dystonia: frequency and clinical features

Do cerebrovascular risk factors impact the clinical expression of idiopathic isolated adult-onset dystonia?

BACKGROUND

Although acquired dystonia may develop following ischaemic/haemorrhagic stroke, the relationship between cerebrovascular disease and idiopathic dystonia has been poorly investigated. This cross sectional study aimed at evaluating the impact of cerebrovascular risk factors on the clinical expression of idiopathic adult onset dystonia (IAOD), with reference to dystonia localization and dystonia-associated features.

METHODS

Data were obtained from the Italian Dystonia Registry. Patients with IAOD were stratified into two groups according to the presence of diabetes mellitus and/or arterial hypertension and/or dyslipidemia and/or heart disease. The two groups were compared for demographic features, dystonia phenotype, and dystonia-associated features (sensory trick, tremor, eye symptoms in blepharospasm, and neck pain in cervical dystonia).

RESULTS

A total of 1108 patients participated into the study. Patients who reported one cerebrovascular factor or more (n = 555) had higher age and longer disease duration than patients who did not. On multivariable logistic regression analysis, blepharospasm was the only localization, and sensory trick was the only dystonia-associated feature that was significantly associated with cerebrovascular risk factors. Linear regression analysis showed that the strength of the association between cerebrovascular factors and blepharospasm/sensory trick increased with increasing the number of cerebrovascular factors per patient.

CONCLUSIONS

Results of the present study showed that cerebrovascular risk factors may be associated with specific features of IAOD that is development of blepharospasm and sensory trick. Further studies are needed to better understand the meaning and the mechanisms underlying this association.

Anatomical categorization of isolated non-focal dystonia: novel and existing patterns using a data-driven approach

According to expert consensus, dystonia can be classified as focal, segmental, multifocal, and generalized, based on the affected body distribution. To provide an empirical and data-driven approach to categorizing these distributions, we used a data-driven clustering approach to compare frequency and co-occurrence rates of non-focal dystonia in pre-defined body regions using the Dystonia Coalition (DC) dataset. We analyzed 1,618 participants with isolated non-focal dystonia from the DC database. The analytic approach included construction of frequency tables, variable-wise analysis using hierarchical clustering and independent component analysis (ICA), and case-wise consensus hierarchical clustering to describe associations and clusters for dystonia affecting any combination of eighteen pre-defined body regions. Variable-wise hierarchical clustering demonstrated closest relationships between bilateral upper legs (distance = 0.40), upper and lower face (distance = 0.45), bilateral hands (distance = 0.53), and bilateral feet (distance = 0.53). ICA demonstrated clear grouping for the a) bilateral hands, b) neck, and c) upper and lower face. Case-wise consensus hierarchical clustering at k = 9 identified 3 major clusters. Major clusters consisted primarily of a) cervical dystonia with nearby regions, b) bilateral hand dystonia, and c) cranial dystonia. Our data-driven approach in a large dataset of isolated non-focal dystonia reinforces common segmental patterns in cranial and cervical regions. We observed unexpectedly strong associations between bilateral upper or lower limbs, which suggests that symmetric multifocal patterns may represent a previously underrecognized dystonia subtype.

A Case of Tardive Dystonia with Task Specificity Confined to the Lower Extremities only during Walking

Background

Task-specific dystonia (TSD) confined to the lower extremities (LE) is relatively rare. This report describes dystonia confined to the LE only during forward walking. This case required careful neurological and diagnostic assessment because the patient was taking several neuropsychiatric drugs that cause symptomatic dystonia, such as aripiprazole (ARP).

Case

A 53-year-old man visited our university hospital with a complaint of abnormalities in the LE that appeared only during walking. Neurological examinations other than walking were normal. Brain magnetic resonance imaging revealed meningioma in the right sphenoid ridge. The patient had been treated for depression with neuropsychiatric medications for a long time, and his abnormal gait appeared about 2 years after additional administration of ARP. After the meningioma was removed, his symptoms remained. Surface electromyography showed dystonia in both LE during forward walking, although his abnormal gait appeared to be accompanied by spasticity. The patient was tentatively diagnosed with tardive dystonia (TD). Although dystonia did not disappear clinically, it was alleviated after discontinuing ARP. Administration of trihexyphenidyl hydrochloride and concomitant rehabilitation improved his dystonia until return to work, but some residual gait abnormalities remained.

Discussion

We report an unusual case of TD with task specificity confined to the LE. The TD was induced by the administration of ARP in combination with multiple psychotropic medications. Careful consideration was required for clinical diagnosis, rehabilitation, and assessment of its relevance to TSD.

Symptom Locus and Symptom Origin Incongruity in Runner's Dystonia - Case Study of an Elite Female Runner

Objectives: Runner's dystonia is a task-specific dystonia that occurs in the lower limbs and trunk, with diverse symptomatology. We aimed to identify the origin of a dystonic movement abnormality using combined three-dimensional kinematic analysis and electromyographic (EMG) assessment during treadmill running. Participant: A 20-year-old female runner who complained of right-foot collision with the left-leg during right-leg swing-phase, which mimicked right-ankle focal dystonia. Results: Kinematic and EMG assessment of her running motion was performed, which showed a significant drop of the left pelvis during right-leg stance-phase, and a simultaneous increase of right hip adductor muscle activity. This resulted in a pronounced adduction of the entire right lower limb with respect to the pelvis segment. Trajectories of right foot were seen to encroach upon left-leg area. Discussion: These findings suggested that the symptom of this runner was most likely a form of segmental dystonia originating from an impaired control of hip and pelvis, rather than a distal focal ankle dystonia. Conclusion: We conclude that, for individualized symptom assessment, deconstructing the symptom origin from its secondary compensatory movement is crucial for characterizing dystonia. Kinematic and EMG evaluation will therefore be a prerequisite to distinguish symptom origin from secondary compensatory movement.

Spread of segmental/multifocal idiopathic adult-onset dystonia to a third body site

BACKGROUND

Adult-onset focal dystonia can spread to involve one, or less frequently, two additional body regions. Spread of focal dystonia to a third body site is not fully characterized.

MATERIALS AND METHODS

We retrospectively analyzed data from the Italian Dystonia Registry, enrolling patients with segmental/multifocal dystonia involving at least two parts of the body or more. Survival analysis estimated the relationship between dystonia features and spread to a third body part.

RESULTS

We identified 340 patients with segmental/multifocal dystonia involving at least two body parts. Spread of dystonia to a third body site occurred in 42/241 patients (17.4%) with focal onset and 10/99 patients (10.1%) with segmental/multifocal dystonia at onset. The former had a greater tendency to spread than patients with segmental/multifocal dystonia at onset. Gender, years of schooling, comorbidity, family history of dystonia/tremor, age at dystonia onset, and disease duration could not predict spread to a third body site. Among patients with focal onset in different body parts (cranial, cervical, and upper limb regions), there was no association between site of focal dystonia onset and risk of spread to a third body site.

DISCUSSION AND CONCLUSION

Spread to a third body site occurs in a relative low percentage of patients with idiopathic adult-onset dystonia affecting two body parts. Regardless of the site of dystonia onset and of other demographic/clinical variables, focal onset seems to confer a greater risk of spread to a third body site in comparison to patients with segmental/multifocal dystonia at onset.

Massage Therapy for Dystonia: a Case Report

BACKGROUND

Dystonia is a neurological disorder, characterized by involuntary muscle spasms and tremors, resulting in abnormal movements and posture. Symptoms include pain, spasms, tremors, and dyskinesia-a difficulty in performing voluntary muscular movements. Conventional treatments include medication, botulism injections, and surgical intervention. Many dystonia patients seek complementary and alternative medicine (CAM) therapies, such as massage, but these treatments are not well documented. This clinical case study documents massage treatment for dystonia for a specific individual.

PURPOSE

To examine the effects of massage therapy on pain, spasms, and dyskinesia in activities of daily living (ADL), in a patient diagnosed with dystonia as an adult, following trauma.

METHODS

A student massage therapist administered 5 massage treatments over a six-week period to a 51-year-old female patient diagnosed with dystonia. The patient presented with symptoms of pain, spasms, tremors, and dyskinesia in ADL. Techniques applied included Swedish massage and hydrotherapy to decrease pain and spasms, and myofascial release and stretching, to decrease dyskinesia. Treatments aimed to increase overall relaxation. Remedial exercise was given to practice smoother movement patterns. Pre- and postnumeric rating scales (NRS) for pain were evaluated each session. Frequency of night pain and spasms, the Modified Bradykinesia Rating Scale (MBRS), the Timed Up and Go (TUG) test, the Functional Rating Index (FRI) and the Modified Gait Efficacy Scale (MGES) were measured at the start and end of the study.

RESULTS

Posttreatment pain intensity generally remained the same or decreased. Positive outcomes were exhibited in the frequency of night pain and spasms, TUG, MBRS, and FRI test scores. The MGES score was negatively affected.

CONCLUSION

The results suggest massage therapy may temporarily decrease pain intensity, pain and spasm frequency, and dyskinesia in ADL, associated with dystonia.

Advances in the pathophysiology of adult-onset focal dystonias: recent neurophysiological and neuroimaging evidence

Focal dystonia is a movement disorder characterized by involuntary muscle contractions that determine abnormal postures. The traditional hypothesis that the pathophysiology of focal dystonia entails a single structural dysfunction (i.e. basal ganglia) has recently come under scrutiny. The proposed network disorder model implies that focal dystonias arise from aberrant communication between various brain areas. Based on findings from animal studies, the role of the cerebellum has attracted increased interest in the last few years. Moreover, it has been increasingly reported that focal dystonias also include nonmotor disturbances, including sensory processing abnormalities, which have begun to attract attention. Current evidence from neurophysiological and neuroimaging investigations suggests that cerebellar involvement in the network and mechanisms underlying sensory abnormalities may have a role in determining the clinical heterogeneity of focal dystonias.

Focal Task-Specific Lower Limb Dystonia Only When Walking Stairs: Is It a New Disease Entity?

Introduction: Focal task-specific dystonia in the lower limb or foot often occurs only during walking, running, hiking, or cycling. Several medications and botulinum toxin injection are effective in patients with this disorder. The objective of this study was to understand the spectrum of focal task-specific dystonia in the lower limb only when walking stairs and to compare other types of task-specific dystonia.

Methods: All original articles and case reports were collected and reviewed using PubMed. In addition, all video clips of published cases were evaluated, and patients' clinical findings analyzed. The present study included 12 patients described in previous studies and five new Asian patients found in the medical records.

Results: Most of the patients were women, and the onset age was 42 years. Ten patients were classified as the Kicking type, including three patients with the rKicking type, and six patients were considered as the Lifting type; however, only one patient was not included in any of the types. Symptoms in most of the patients did not improve with any medications or botulinum toxin injection. The symptoms of most patients did not change over a long time.

Conclusion: Most patients showed the dystonic symptom when walking downstairs rather than upstairs. Psychogenic dystonia is a disease differentially diagnosed with this dystonia. Unlike other types of focal task-specific dystonia, the response to treatment was disappointing because most of the medications and botulinum toxin injection were not effective. The prognosis is completely different from that of other types of focal task-specific dystonia.

Expert recommendations for diagnosing cervical, oromandibular, and limb dystonia

BACKGROUND

Diagnosis of focal dystonia is based on clinical grounds and is therefore open to bias. To date, diagnostic guidelines have been only proposed for blepharospasm and laryngeal dystonia. To provide practical guidance for clinicians with less expertise in dystonia, a group of Italian Movement Disorder experts formulated clinical diagnostic recommendations for cervical, oromandibular, and limb dystonia.

METHODS

A panel of four neurologists generated a list of clinical items related to the motor phenomenology of the examined focal dystonias and a list of clinical features characterizing neurological/non-neurological conditions mimicking dystonia. Thereafter, ten additional expert neurologists assessed the diagnostic relevance of the selected features and the content validity ratio was calculated. The clinical features reaching a content validity ratio > 0.5 contributed to the final recommendations.

RESULTS

The recommendations retained patterned and repetitive movements/postures as the core feature of dystonia in different body parts. If present, a sensory trick confirmed diagnosis of dystonia. In the patients who did not manifest sensory trick, active exclusion of clinical features related to conditions mimicking dystonia (features that would be expected to be absent in dystonia) would be necessary for dystonia to be diagnosed.

DISCUSSION

Although reliability, sensitivity, and specificity of the recommendations are yet to be demonstrated, information from the present study would hopefully facilitate diagnostic approach to focal dystonias in the clinical practice and would be the basis for future validated diagnostic guidelines.

Muscle Selection for Focal Limb Dystonia

Selection of muscles for botulinum toxin injection for limb dystonia is particularly challenging. Limb dystonias vary more widely in the pattern of dystonic movement and involved muscles than cervical dystonia or blepharospasm. The large variation in how healthy individuals perform skilled hand movements, the large number of muscles in the hand and forearm, and the presence of compensatory actions in patients with dystonia add to the complexity of choosing muscles for injection. In this article, we discuss approaches to selecting upper and lower extremity muscles for chemodenervation treatment of limb dystonia.

Down the Stairs Dystonia-A Novel Task-Specific Focal Isolated Syndrome

Adult-onset, task-specific dystonia of the lower limb is a rare occurrence. In this report, the authors present 6 cases of task-specific dystonia manifested only when going down the stairs. These patients were seen by 6 different neurologists from across Canada, Australia, and New Zealand, and all videos were reviewed by 1 movement disorders specialist who made the final diagnosis. Video description of each case is also presented. All 6 patients demonstrated dystonia of 1 of their lower limbs specifically only when going down the stairs. The remainder of the neurological examination was normal, and distractibility, inconsistency, fixed dystonia, or a premonitory urge were absent, making functional movement disorder and tic disorder unlikely. These 6 patients display a distinct, adult-onset, focal isolated dystonia manifested only on going down the stairs that is recognizable as a new task-specific dystonia of the lower extremity.

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.

Diagnosis of primary task-specific lower extremity dystonia in a runner

STUDY DESIGN

Resident's case problem.

BACKGROUND

A 56-year-old man was referred to physical therapy for analysis of unusual gait, first noticed 3 years previously when running. Prior to this evaluation, the patient had seen multiple orthopaedic, sports medicine, and neurological specialists while undergoing repeated and extensive testing. Ten months of testing and treatment, including conservative and surgical management, did not provide an explanation for the gait abnormality or result in improvement of the patient's condition.

DIAGNOSIS

The patient's physical examination was relatively unremarkable, considering the severity of the gait abnormality. Distinct abnormalities were apparent with computerized gait analysis and dynamic electromyography, and, when combined with the physical examination findings, led to a suspicion of the task-specific disorder of runner's dystonia. The patient was referred to a neurologist specializing in movement-related disorders, with a final confirmed diagnosis of primary task-specific dystonia with first onset during running (ie, runner's dystonia).

DISCUSSION

Idiopathic, task-specific dystonia of the lower extremity is documented as a very rare occurrence, yet increasing trends in running participation may result in a higher incidence of this condition. Improved awareness of runner's dystonia in the present case might have enhanced the clinical decision-making process and resulted in more timely and effective treatment solutions. Clinical examination findings, including computerized gait analysis and electromyography, in conjunction with imaging, blood, and genetic testing, can aid in the diagnosis of runner's dystonia.

LEVEL OF EVIDENCE

Differential diagnosis, level 4.

Current and future medical treatment in primary dystonia

Dystonia is a hyperkinetic movement disorder, characterized by involuntary and sustained contractions of opposing muscles causing twisting movements and abnormal postures. It is often a disabling disorder that has a significant impact on physical and psychosocial wellbeing. The medical therapeutic armamentarium used in practice is quite extensive, but for many of these interventions formal proof of efficacy is lacking. Exceptions are the use of botulinum toxin in patients with cervical dystonia, some forms of cranial dystonia (in particular, blepharospasm) and writer's cramp; deep brain stimulation of the pallidum in generalized and segmental dystonia; and high-dose trihexyphenidyl in young patients with segmental and generalized dystonia. In order to move this field forward, we not only need better trials that examine the effect of current treatment interventions, but also a further understanding of the pathophysiology of dystonia as a first step to design and test new therapies that are targeted at the underlying biologic and neurophysiologic mechanisms.

Clinical phenomenology of dystonia

Dystonia is defined as a motor syndrome characterized by sustained muscle contractions, usually producing twisting and repetitive movements or abnormal postures. Dystonia can be present at rest or worsened by action. Dystonia is commonly classified according to age at onset (childhood, adolescent type, and adult type), etiology (idiopathic, and symptomatic), and distribution (focal dystonia, segmental dystonia, generalized dystonia, multifocal dystonia and hemidystonia). The different subtypes of focal and segmental dystonias may have different clinical features. Neuropsychiatric disorders may be present in dystonia.