Paramedical treatment in primary dystonia: a systematic review

Treating Dystonia in a Soccer Player Through an Integrated Rehabilitative Approach: A Case Report

CONTEXT

Sport-related dystonia is a rare form of activity-specific dystonia that can severely impair an athlete's ability to perform. Due to a lack of data on the condition, it is difficult to diagnose and often overlooked, and no gold standard treatment has yet been defined.

CASE PRESENTATION

We present a rare and challenging case of sport-related dystonia that affected a 24-year-old male professional soccer player. The patient presented with severe rigidity and dystonia of the right lower-extremity, particularly the ankle and foot. The symptoms set on >1 year prior to the presentation to our outpatient clinic. He began to complain of stiffness and difficulty moving his lower limbs, especially his right leg, initially when playing soccer, but then also when walking normally. On presentation, he was unable to run and walked with difficulty, supporting his body weight only on the outside of his right foot. He also reported a motor trick and reverse motor trick involving the oral musculature in order to move his lower limb more freely.

MANAGEMENT AND OUTCOMES

An integrated rehabilitation approach based on postural rehabilitation, neuromuscular rehabilitation, and dental intervention was used to successfully treat this condition. The approach included: (1) postural rehabilitation with the Mézières-Bertelè method to reduce muscular stiffness, (2) neuromuscular re-education with Tai Chi exercises and electromyography-guided biofeedback, and (3) dental intervention and swallowing rehabilitation to limit impaired oral habits (due to the relationship between his impaired lower limb movements and motor tricks of the oral musculature). After 7 months of integrated rehabilitation, the patient returned to professional soccer.

CONCLUSIONS

This case report highlights the potential efficacy of an integrative rehabilitation approach for sports dystonia, particularly in cases where traditional treatments may not be effective. Such an approach could be considered a valuable option in the management of this rare, but debilitating, condition in athletes. Further research is needed to assess the effectiveness of this approach in larger populations.

Botulinum toxin and conservative treatment strategies in people with cervical dystonia: an online survey

Isolated cervical dystonia is a focal, idiopathic dystonia affecting the neck muscles. Treatment usually consists of botulinum neurotoxin (BoNT) injections into the dystonic muscles. Our aim is to investigate the use of BoNT treatment and conservative treatments by people living with cervical dystonia. An online survey in English was conducted between June and August 2022. Participants were eligible to participate if they were living with cervical dystonia, were over 18 years old and could read and understand English. The survey consisted of demographic questions, characteristics of dystonia, questions relating to BoNT use and the perceived utility of conservative treatments. The data were analysed descriptively, and open-ended questions were grouped into similar topics represented by direct quotes. We received 128 responses from people with cervical dystonia, with an average age of 59 years and 77% women. Most participants (52%) described their cervical dystonia as mild to moderate with an average pain score of 5/10. Eighty-two (64%) participants were having regular BoNT injections, with overall positive perceived effects. Common activities reported to improve the symptoms were the use of heat packs, massage, relaxation, physiotherapy and participation in general exercise. Common coping strategies reported were getting sufficient rest, having the support of friends and family, and remaining engaged in enjoyable hobbies. We found that most participants received regular BoNT injections and that heat packs, exercise, massage, physiotherapy and relaxation were mostly perceived as effective in reducing the symptoms of cervical dystonia.

Pain in cervical dystonia: mechanisms, assessment and treatment

INTRODUCTION

In patients with cervical dystonia (CD), pain is a major contributor to disability and social isolation and is often the main reason patients seek treatment. Surveys evaluating patient perceptions of their CD symptoms consistently highlight pain as a troublesome and disabling feature of their condition with significant impact on daily life and work.

AREAS COVERED

In this article, the authors review the epidemiology, assessment, possible mechanisms and treatment of pain in CD, including a meta-analysis of randomized controlled trial data with abobotulinumtoxinA.

EXPERT OPINION

Mechanisms of pain in CD may be muscle-based and non-muscle based. Accumulating evidence suggests that non-muscle-based mechanisms (such as abnormal transmission and processing of nociceptive stimuli, dysfunction of descending pain inhibitory pathways as well as structural and network changes in the basal ganglia, cortex and other areas) may also contribute to pain in CD alongside prolonged muscle contraction. Chemodenervation with botulinum toxin is considered the first-line treatment for CD. Treatment with botulinum toxin is usually effective, but optimization of the injection parameters should include consideration of pain as a core symptom in addition to the motor problems.

The Progress of the Gait Impairment and Brain Activation in a Patient with Post-stroke Hemidystonia

OBJECTIVE

We explore the effects of body weight-supported (BWS) treadmill training, including the change of cortical activation, on a patient with post-stroke hemidystonia.

PATIENT

The patient was a 71-year-old man with left thalamus hemorrhage. His motor symptoms indicated slight impairment. There was no overactive muscle contraction in the supine, sitting, or standing positions. During his gait, the right initial contact was the forefoot, and his right knee showed an extension thrust pattern. These symptoms suggested that he had post-stroke hemidystonia.

METHODS

The patient performed BWS treadmill training 14 times over 3 weeks. The effects of the BWS training were assessed by a step-length analysis, electromyography and functional magnetic resonance imaging (fMRI).

RESULTS

The patient's nonparetic step length was extended significantly in the Inter-BWS (p<0.001) and Post-BWS (p=0.025) periods compared to the Pre-BWS session. The excessive muscle activity of the right gastrocnemius medialis in the swing phase was decreased at the Inter-BWS, Post-BWS, and follow-up compared to the Pre-BWS session. The peak timing difference of the bilateral tibialis anterior muscle became significant (p<0.05) on the first day of the intervention. The fMRI revealed that the cortical areas activated by the motor task converged through the intervention (p<0.05, family-wise error corrected).

CONCLUSION

These results suggest that there was improvement of the patient's symptoms of post-stroke hemidystonia due to changes in the brain activity during voluntary movement after BWS intervention. Body weight-supported treadmill training may thus be an effective treatment for patients with poststroke hemidystonia.

Best Practices in the Clinical Management of Progressive Supranuclear Palsy and Corticobasal Syndrome: A Consensus Statement of the CurePSP Centers of Care

Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS; the most common phenotype of corticobasal degeneration) are tauopathies with a relentless course, usually starting in the mid-60s and leading to death after an average of 7 years. There is as yet no specific or disease-modifying treatment. Clinical deficits in PSP are numerous, involve the entire neuraxis, and present as several discrete phenotypes. They center on rigidity, bradykinesia, postural instability, gait freezing, supranuclear ocular motor impairment, dysarthria, dysphagia, incontinence, sleep disorders, frontal cognitive dysfunction, and a variety of behavioral changes. CBS presents with prominent and usually asymmetric dystonia, apraxia, myoclonus, pyramidal signs, and cortical sensory loss. The symptoms and deficits of PSP and CBS are amenable to a variety of treatment strategies but most physicians, including many neurologists, are reluctant to care for patients with these conditions because of unfamiliarity with their multiplicity of interacting symptoms and deficits. CurePSP, the organization devoted to support, research, and education for PSP and CBS, created its CurePSP Centers of Care network in North America in 2017 to improve patient access to clinical expertise and develop collaborations. The directors of the 25 centers have created this consensus document outlining best practices in the management of PSP and CBS. They formed a writing committee for each of 12 sub-topics. A 4-member Steering Committee collated and edited the contributions. The result was returned to the entire cohort of authors for further comments, which were considered for incorporation by the Steering Committee. The authors hope that this publication will serve as a convenient guide for all clinicians caring for patients with PSP and CBS and that it will improve care for patients with these devastating but manageable disorders.

Cerebellar 5HT-2A receptor mediates stress-induced onset of dystonia

Stress is a key risk factor for dystonia, a debilitating motor disorder characterized by cocontractions of muscles leading to abnormal body posture. While the serotonin (5HT) system is known to control emotional responses to stress, its role in dystonia remains unclear. Here, we reveal that 5HT neurons in the dorsal raphe nuclei (DRN) send projections to the fastigial deep cerebellar nuclei (fDCN) and that photostimulation of 5HT-fDCN induces dystonia in wild-type mice. Moreover, we report that photoinhibition of 5HT-fDCN reduces dystonia in a1A ^tot/tot mice, a genetic model of stress-induced dystonia, and administration of a 5HT-2A receptor inverse agonist (MDL100907; 0.1 to 1 mg/kg) or shRNA-mediated knockdown of the ht2ar gene in fDCN can notably reduce the onset of dystonia in a1A ^tot/tot mice. These results support the serotonin theory of dystonia and suggest strategies for alleviating symptoms in human patients by blocking 5HT-2A receptors.

Neurorehabilitation in dystonia: a holistic perspective

Rehabilitation for isolated forms of dystonia, such as cervical or focal hand dystonia, is usually targeted towards the affected body part and focuses on sensorimotor control and motor retraining of affected muscles. Recent evidence, has revealed people who live with dystonia experience a range of functional and non-motor deficits that reduce engagement in daily activities and health-related quality of life, which should be addressed with therapeutic interventions. These findings support the need for a holistic approach to the rehabilitation of dystonia, where assessment and treatments involve non-motor signs and symptoms, and not just the dystonic body part. Most studies have investigated Cervical Dystonia, and in this population, it is evident there is reduced postural control and walking speed, high fear of falling and actual falls, visual compensation for the impaired neck posture, and a myriad of non-motor symptoms including pain, fatigue, sleep disorders and anxiety and depression. In other populations of dystonia, there is also emerging evidence of falls and reduced vision-related quality of life, along with the inability to participate in physical activity due to worsening of dystonic symptoms during or after exercise. A holistic approach to dystonia would support the management of a wide range of symptoms and signs, that if properly addressed could meaningfully reduce disability and improve quality of life in people living with dystonia.

Four-Repeat Tauopathies: Current Management and Future Treatments

Four-repeat tauopathies are a neurodegenerative disease characterized by brain parenchymal accumulation of a specific isoform of the protein tau, which gives rise to a wide breadth of clinical syndromes encompassing diverse symptomatology, with the most common syndromes being progressive supranuclear palsy-Richardson's and corticobasal syndrome. Despite the lack of effective disease-modifying therapies, targeted treatment of symptoms can improve quality of life for patients with 4-repeat tauopathies. However, managing these symptoms can be a daunting task, even for those familiar with the diseases, as they span motor, sensory, cognitive, affective, autonomic, and behavioral domains. This review describes current approaches to symptomatic management of common clinical symptoms in 4-repeat tauopathies with a focus on practical patient management, including pharmacologic and nonpharmacologic strategies, and concludes with a discussion of the history and future of disease-modifying therapeutics and clinical trials in this population.

Sensorimotor Perceptive Rehabilitation Integrated (SPRInt) program: exercises with augmented movement feedback associated to botulinum neurotoxin in idiopathic cervical dystonia-an observational study

BACKGROUND

Idiopathic cervical dystonia (ICD) is a focal dystonia affecting neck muscles. Botulinum neurotoxin (BoNT) is the first-line treatment of ICD and different physical therapies (including exercise) are often proposed as adjunct treatments. However, the actual effectiveness of exercise in ICD is unclear. The aim of the current work is to assess the potential effectiveness of the Sensorimotor Perceptive Rehabilitation Integrated (SPRInt) exercise program as adjunct therapy for ICD.

METHODS

Fifteen ICD patients received BoNT injections in the neck muscles and, 12 weeks later, received BoNT a second time and SPRInt started. SPRInt consists in 18 exercise sessions in which augmented feedback of movement (including visual and acoustic feedback) is extensively used. Dystonia burden was measured by the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS). Patients were evaluated immediately before, 6 and 12 weeks after each BoNT injection.

RESULTS

Six weeks after the first BoNT injection (i.e., at BoNT peak effect), TWSTRS total score was better than baseline and remained improved at 12 weeks. TWSTRS disability domain slightly improved 6 weeks after the first BoNT injection, but after 6 more weeks returned to its baseline level. Disability improved more at SPRInt end (i.e., 6 weeks after the second BoNT injection), being even lower than after toxin alone. With a single-subject analysis, 4/10 patients who did not improve disability after BoNT improved after SPRInt plus BoNT.

CONCLUSIONS

SPRInt plus BoNT can be more effective than BoNT alone in improving cervical dystonia patients' difficulties in the activities of daily living.

TRIAL REGISTRATION

www.ClinicalTrials.gov, identifier NCT03247868 (https://register.clinicaltrials.gov).

Update on current and emerging therapies for dystonia

Treatment strategies for dystonia depend on the focal, segmental or generalized distribution of symptoms. Chemodenervation with botulinum toxin remains the treatment of choice for focal- or select-body regions in generalized and segmental dystonia. A potentially longer acting formulation of botulinum toxin is being investigated besides the currently available formulations. Electromyography increases toxin injection accuracy and may reduce injection number, frequency, side effects and costs by identifying dystonic muscle activity. Oral anticholinergics, baclofen and clonazepam are used off-label, but novel drugs in development include sodium oxybate, zonisamide and perampanel. Characterizing dystonia as a sensorimotor circuit disorder has prompted the use of noninvasive neuromodulation procedures. These techniques need further study but simultaneous rehabilitation techniques appear to also improve outcomes. Pallidal deep-brain stimulation is beneficial for medication-refractory primary generalized and possibly focal dystonia such as cervical dystonia. Certain genetic conditions are amenable to specific therapies and future gene-targeted therapies could benefit selected dystonia patients.

Long-Term Specialized Physical Therapy in Cervical Dystonia: Outcomes of a Randomized Controlled Trial

OBJECTIVE

To evaluate the effectiveness of a specialized physical therapy (SPT) program on disability in cervical dystonia (CD) compared to regular physical therapy (RPT).

DESIGN

A single-blinded randomized controlled trial.

SETTING

This study was performed by a physical therapist in a primary health care setting. Measurements were performed at baseline, 6 and 12 months in the botulinum toxin (BoNT) outpatient clinic of the neurology department.

PARTICIPANTS

Patients with primary CD and stable on BoNT treatment for 1 year (N=96).

MAIN OUTCOME MEASURES

The primary outcome was disability assessed with the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS). Secondary outcomes were pain, anxiety, depression, quality of life (QOL), and health related costs over 12 months.

RESULTS

A total of 72 participants (30 men, 42 women) finished the study: 40 received SPT, 32 RPT. No significant between group differences were found after 12 months of treatment (P=.326). Over these 12 months both groups improved significantly (P<.001) on the TWSTRS disability scale compared to baseline (SPT 1.7 points, RPT 1.0 points). Short Form 36 (SF-36) General Health Perceptions (P=.046) and self-perceived improvement (P=.007) showed significantly larger improvements after 12 months in favor of SPT. Total health related costs after 12 months were $1373±556 for SPT compared to $1614±917 for RPT.

CONCLUSION

SPT revealed no significant differences compared to RPT after 12 months of treatment on the TWSTRS disability scale. Both groups showed similar improvements compared to baseline. Positive results in the SPT group were higher patient perceived effects and general health perception. Treatment costs were lower in the SPT group. With lower costs and similar effects, the SPT program seems to be the preferred program to treat CD.

Systematic Review of Rehabilitation in Focal Dystonias: Classification and Recommendations

Background

Rehabilitation interventions are rarely utilized as an alternative or adjunct therapy for focal dystonias. Reasons for limited utilization are unknown, but lack of conclusive evidence of effectiveness is likely a crucial factor.

Methods and Findings

The purpose of this systematic review was to determine the level of evidence for rehabilitation interventions in focal dystonias. Rehabilitation interventions were classified based upon the underlying theoretical basis of different approaches, and the strength of evidence for each category was evaluated to identify gaps in the field. Prospective studies using rehabilitation methods in cervical, hand, and foot dystonia were reviewed. The key elements of treatments tested were identified and studies were grouped into six categories based on the theoretical basis of the intervention: (1) movement practice, (2) training with constraint, (3) sensory reorganization, (4) normalization of muscle activity with external techniques, (5) neuromodulation with training, and (6) compensatory strategies. Quality of the body of evidence ranged from very low‐to‐low according to the grades of recommendation, assessment, development, and evaluation (GRADE). Despite inconclusive evidence for these rehabilitation approaches, data suggest that intensive movement practice and neuromodulation combined with motor training should be further explored.

Conclusions

This systematic review presents a novel approach to classify studies of rehabilitation in focal dystonias based on the theoretical basis of intervention. The proposed classification system will move toward a unified theoretical understanding of rehabilitation interventions in dystonia. Moreover, it will help provide recommendations for clinical applications and future investigations.

Dystonia

INTRODUCTION

Dystonia is a clinically heterogeneous group of hyperkinetic movement disorders. Recent advances have provided a better understanding of these conditions with significant clinical impact.

SOURCES OF DATA

Peer reviewed journals and reviews. PubMed.gov.

AREAS OF AGREEMENT

A recent consensus classification, including the assessment of phenomenology and identification of the dystonia syndromes, has provided a helpful tool for the clinical assessment. New forms of monogenic dystonia have been recently identified.

AREAS OF CONTROVERSY

Despite recent advances in the understanding of dystonia, treatment remains symptomatic in most patients.

GROWING POINTS

Recent advances in genetics have provided a better understanding of the potential pathogenic mechanisms involved in dystonia. Deep brain stimulation has shown to improve focal and combined forms of dystonia and its indications are constantly expanding.

AREAS TIMELY FOR DEVELOPING RESEARCH

Growing understanding of the disease mechanisms involved will allow the development of targeted and disease-modifying therapies in the future.

Research Priorities in Limb and Task-Specific Dystonias

Dystonia, which causes intermittent or sustained abnormal postures and movements, can present in a focal or a generalized manner. In the limbs, focal dystonia can occur in either the upper or lower limbs and may be task-specific causing abnormal motor performance for only a specific task, such as in writer’s cramp, runner’s dystonia, or musician’s dystonia. Focal limb dystonia can be non-task-specific and may, in some circumstances, be associated with parkinsonian disorders. The true prevalence of focal limb dystonia is not known and is likely currently underestimated, leaving a knowledge gap and an opportunity for future research. The pathophysiology of focal limb dystonia shares some commonalities with other dystonias with a loss of inhibition in the central nervous system and a loss of the normal regulation of plasticity, called homeostatic plasticity. Functional imaging studies revealed abnormalities in several anatomical networks that involve the cortex, basal ganglia, and cerebellum. Further studies should focus on distinguishing cause from effect in both physiology and imaging studies to permit focus on most relevant biological correlates of dystonia. There is no specific therapy for the treatment of limb dystonia given the variability in presentation, but off-label botulinum toxin therapy is often applied to focal limb and task-specific dystonia. Various rehabilitation techniques have been applied and rehabilitation interventions may improve outcomes, but small sample size and lack of direct comparisons between methods to evaluate comparative efficacy limit conclusions. Finally, non-invasive and invasive therapeutic modalities have been explored in small studies with design limitations that do not yet clearly provide direction for larger clinical trials that could support new clinical therapies. Given these gaps in our clinical, pathophysiologic, and therapeutic knowledge, we have identified priorities for future research including: the development of diagnostic criteria for limb dystonia, more precise phenotypic characterization and innovative clinical trial design that considers clinical heterogeneity, and limited available number of participants.

Quality of life in cervical dystonia after treatment with botulinum toxin A: a 24-week prospective study

OBJECTIVE

This study aimed to identify possible improvements in disease-specific health-related quality of life (HRQoL) after multiple injections of botulinum toxin A over 24 weeks in Thai cervical dystonia (CD) patients.

MATERIALS AND METHODS

A 24-week prospective study comparing HRQoL of Thai CD patients before and after multiple injections of botulinum toxin A at 3-month intervals was performed. Disease-specific HRQoL was assessed by using the Cervical Dystonia Impact Profile-58 questionnaire (CDIP-58) and the Craniocervical Dystonia Questionnaire-24 (CDQ-24). General HRQoL was assessed by using the Medical Outcomes' 36-Item Short Form Health Survey (SF-36) and the EuroQoL 5-dimension questionnaire (EQ-5D). All the assessments were performed before and after the 24-week treatment period.

RESULTS

A total of 20 CD patients were enrolled in this study from April to December 2011. CDIP-58 and CDQ-24 scores, which assess disease-specific HRQoL, showed a significant improvement after 24 weeks of treatment by botulinum toxin A (P<0.001). However, EQ-5D and SF-36 scores, which assess general HRQoL, showed no significant improvement after the treatment (P>0.05).

CONCLUSION

CD patients' disease-specific HRQoL improved after being treated with multiple botulinum toxin A injections. However, general HRQoL was not improved.

Unmet Needs in the Management of Cervical Dystonia

Cervical dystonia (CD) is a movement disorder which affects daily living of many patients. In clinical practice, several unmet treatment needs remain open. This article focuses on the four main aspects of treatment. We describe existing and emerging treatment approaches for CD, including botulinum toxin injections, surgical therapy, management of non-motor symptoms, and rehabilitation strategies. The unsolved issues regarding each of these treatments are identified and discussed, and possible future approaches and research lines are proposed.

Behavioural interventions for people living with adult-onset primary dystonia: a systematic review

BACKGROUND

Primary dystonia is a chronic neurological movement disorder that causes abnormal muscle movements. Pain and emotional distress may accompany these physical symptoms. Behavioural interventions are used to help people with long term conditions improve their quality of life. Little is known about behavioural interventions applied to Dystonia. We report a systematic review of studies reporting current evidence of behavioural interventions for people with primary dystonia.

METHODS

We did systematic searches of Medline, PsycINFO, AHMED and CINAHL. We assessed the methodological quality of included studies using a risk of bias tool. Any disagreements were resolved by liaising with an independent rater. Physiological outcomes such as dystonia severity and psychological outcomes such as sleep and depression were selected on the basis that primary dystonia causes motor and non-motor symptoms. No time limit was placed on the searches. A narrative synthesis of the results is presented.

RESULTS

Of 1798 titles and abstracts screened, 14 full articles were retrieved and inclusion and exclusion criteria applied. Of these a final nine were eligible for the review (N = 73). Only two were Randomised Controlled Trials (RCTs). Using the Movement Disorders Society (MDS) dystonia classification, that was published after this work started, all of the included studies were of idiopathic adult onset focal dystonia without associated features. These included: blepharospasm (eye dystonia) (N = 1), cervical dystonia (neck dystonia) (N = 2), writer's cramp (hand dystonia) (N = 3) and the yips (N = 3). No studies reported on dystonia that affects two or more body regions. Studies reported good adherence and response rates to treatment. Physiological and psychological improvements were noted in all studies at weekly, monthly and yearly follow-ups. Caution should be taken when interpreting the results because of the scarcity of RCTs identified, use of small sample sizes, and inappropriate statistical methods.

CONCLUSION

We identified few studies; mainly of poor methodological quality that all studied a focal dystonia. It is not possible to draw firm conclusions. Nevertheless, the data suggests that a combined behavioural therapy approach including relaxation practice for people with idiopathic adult onset focal dystonia merits further investigation.

A randomized trial of specialized versus standard neck physiotherapy in cervical dystonia

BACKGROUND

Anecdotal reports suggested that a specialized physiotherapy technique developed in France (the Bleton technique) improved primary cervical dystonia. We evaluated the technique in a randomized trial.

METHODS

A parallel-group, single-blind, two-centre randomized trial compared the specialized outpatient physiotherapy programme given by trained physiotherapists up to once a week for 24 weeks with standard physiotherapy advice for neck problems. Randomization was by a central telephone service. The primary outcome was the change in the total Toronto Western Spasmodic Torticollis Rating (TWSTR) scale, measured before any botulinum injections that were due, between baseline and 24 weeks evaluated by a clinician masked to treatment. Analysis was by intention-to-treat.

RESULTS

110 patients were randomized (55 in each group) with 24 week outcomes available for 84. Most (92%) were receiving botulinum toxin injections. Physiotherapy adherence was good. There was no difference between the groups in the change in TWSTR score over 24 weeks (mean adjusted difference 1.44 [95% CI -3.63, 6.51]) or 52 weeks (mean adjusted difference 2.47 [-2.72, 7.65]) nor in any of the secondary outcome measures (Cervical Dystonia Impact Profile-58, clinician and patient-rated global impression of change, mean botulinum toxin dose). Both groups showed large sustained improvements compared to baseline in the TWSTR, most of which occurred in the first four weeks. There were no major adverse events. Subgroup analysis suggested a centre effect.

CONCLUSION

There was no statistically or clinically significant benefit from the specialized physiotherapy compared to standard neck physiotherapy advice but further trials are warranted.

Diagnosis and treatment of dystonia

The dystonias are a group of disorders characterized by excessive involuntary muscle contractions leading to abnormal postures and/or repetitive movements. A careful assessment of the clinical manifestations is helpful for identifying syndromic patterns that focus diagnostic testing on potential causes. If a cause is identified, specific etiology-based treatments may be available. In most cases, a specific cause cannot be identified, and treatments are based on symptoms. Treatment options include counseling, education, oral medications, botulinum toxin injections, and several surgical procedures. A substantial reduction in symptoms and improved quality of life is achieved in most patients by combining these options.

Dystonia

PURPOSE OF REVIEW

The purpose of this review is to provide an update on the classification, phenomenology, pathophysiology, and treatment of dystonia.

RECENT FINDINGS

A revised definition based on the main phenomenologic features of dystonia has recently been developed in an expert consensus approach. Classification is based on two main axes: clinical features and etiology. Currently, genes have been reported for 14 types of monogenic isolated and combined dystonia. Isolated dystonia (with dystonic tremor) can be caused by mutations in TOR1A (DYT1), TUBB4 (DYT4), THAP1 (DYT6), PRKRA (DYT16), CIZ1 (DYT23), ANO3 (DYT24), and GNAL (DYT25). Combined dystonias (with parkinsonism or myoclonus) are further subdivided into persistent (GCHI [DYT5], SGCE [DYT11], and ATP1A3 [DYT12], with TAF1 most likely but not yet proven to be linked to DYT3) and paroxysmal (PNKD [DYT8], PRRT2 [DYT10], and SLC2A1 [DYT18]). Recent insights from neurophysiologic studies identified functional abnormalities in two networks in dystonia: the basal ganglia-sensorimotor network and, more recently, the cerebellothalamocortical pathway. Besides the well-known lack of inhibition at different CNS levels, dystonia is specifically characterized by maladaptive plasticity in the sensorimotor cortex and loss of cortical surround inhibition. The exact role (modulatory or compensatory) of the cerebellar-cortical pathways still has to be further elucidated. In addition to botulinum toxin for focal forms, deep brain stimulation of the globus pallidus internus is increasingly recognized as an effective treatment for generalized and segmental dystonia.

SUMMARY

The revised classification and identification of new genes for different forms of dystonia, including adult-onset segmental dystonia, enable an improved diagnostic approach. Recent pathophysiologic insights have fundamentally contributed to a better understanding of the disease mechanisms and impact on treatment, such as functional neurosurgery and nonpharmacologic treatment options.

The effectiveness of physiotherapy for cervical dystonia: a systematic literature review

Cervical dystonia is a form of adult-onset, focal dystonia characterized by involuntary contractions of the neck muscles, leading to a disabling, abnormal head posture. CD has a great impact on the activities of daily living (ADL) and quality of life. Currently, the most widely used and recommended first line treatment is botulinum toxin type A (BoNT/A) injections. Physiotherapy is a potentially useful adjuvant, but little is known about its effectiveness. Consequently, our objective was to investigate the effectiveness of physiotherapy alone or as an adjuvant treatment to BoNT/A injections in cervical dystonia (CD) by means of a systematic literature review. Two online databases, PubMed and Web of Science, were searched for articles describing the effectiveness of physiotherapy treatment for CD. After screening, based on predefined in- and exclusion criteria, 16 studies were retained. Their methodological quality was assessed according to Cochrane guidelines. The methodological quality of most studies was low. Examples of shortcomings are small sample sizes, lack of randomization or blinding, and diversity in therapeutic techniques and outcome measures. Only seven studies were clinical trials; the remaining were either case reports or case series. The reported physiotherapy treatments included EMG biofeedback training, muscular elongation, postural exercises and electrotherapy. Improvements in head position, pain, cervical range of motion, quality of life and ADL have been reported, which is promising. Cautious interpretation on the effectiveness of physiotherapy as an adjuvant therapy is required. Before firm conclusions can be drawn, additional high quality trials are needed.

Musician's dystonia in pianists: long-term evaluation of retraining and other therapies

OBJECTIVE

Musician's dystonia is characterized by loss of voluntary motor control in extensively trained movements on an instrument. The condition is difficult to treat. This retrospective study reports on the interventions received by a homogeneous cohort of pianists with musician's dystonia and the subjective and objective changes reported in task performance.

METHODS

This is a retrospective descriptive study. Fifty four pianists with musician's dystonia who had received care in a Movement Disorders Clinic completed a self report questionnaire regarding type and effectiveness of treatment received over the last 4 years. Pianists' fine motor control was assessed objectively by measuring the temporal regularity of their scale playing.

RESULTS

Nearly all patients (98.0%) reported deficits in motor tasks other than musical playing. Half of the patients were taking medications (Botulinum toxin (53%), Trihexyphenidyl (51%)). Subjects reported participating in multiple therapies: retraining (87%), hand therapy (42%), relaxation techniques (38%), physiotherapy (30%), psychotherapy (23%), acupuncture (21%) and body techniques (21%). Self-reported improvements in motor performance were reported by 81.5% of the subjects with 5.6% reporting a complete recovery. Objective gains in task-specific motor performance were documented in 42.9% of the subjects (with deterioration in 4.8%). Retraining therapy, relaxation techniques and change in teacher explained 52% of the variance in subjective outcomes.

CONCLUSIONS

Musician's dystonia not only interferes with musical performance but other fine motor tasks. Objectively, approximately 50% of patients improved task performance following participation in a variety of intervention strategies, but subjectively, 80% of subjects reported improvement.

Rating scales for musician's dystonia: the state of the art

Musician's dystonia (MD) is a focal adult-onset dystonia most commonly involving the hand. It has much greater relative prevalence than non-musician's focal hand dystonias, exhibits task specificity at the level of specific musical passages, and is a particularly difficult form of dystonia to treat. For most MD patients, the diagnosis confirms the end of their music performance careers. Research on treatments and pathophysiology is contingent upon measures of motor function abnormalities. In this review, we comprehensively survey the literature to identify the rating scales used in MD and the distribution of their use. We also summarize the extent to which the scales have been evaluated for their clinical utility, including reliability, validity, sensitivity, specificity to MD, and practicality for a clinical setting. Out of 135 publications, almost half (62) included no quantitative measures of motor function. The remaining 73 studies used a variety of choices from among 10 major rating scales. Most used subjective scales involving either patient or clinician ratings. Only 25% (18) of the studies used objective scales. None of the scales has been completely and rigorously evaluated for clinical utility. Whether studies involved treatments or pathophysiologic assays, there was a heterogeneous choice of rating scales used with no clear standard. As a result, the collective interpretive value of those studies is limited because the results are confounded by measurement effects. We suggest that the development and widespread adoption of a new clinically useful rating scale is critical for accelerating basic and clinical research in MD.

Cervical dystonia: effectiveness of a standardized physical therapy program; study design and protocol of a single blind randomized controlled trial

Background

Cervical dystonia is characterized by involuntary muscle contractions of the neck and abnormal head positions that affect daily life activities and social life of patients. Patients are usually treated with botulinum toxin injections into affected neck muscles to relief pain and improve control of head postures. In addition, many patients are referred for physical therapy to improve their ability to perform activities of daily living. A recent review on allied health interventions in cervical dystonia showed a lack of randomized controlled intervention studies regarding the effectiveness of physical therapy interventions.

Methods/design

The (cost-) effectiveness of a standardized physical therapy program compared to regular physical therapy, both as add-on treatment to botulinum toxin injections will be determined in a multi-centre, single blinded randomized controlled trial with 100 cervical dystonia patients. Primary outcomes are disability in daily functioning assessed with the disability subscale of the Toronto Western Spasmodic Torticollis Rating Scale. Secondary outcomes are pain, severity of dystonia, active range of motion of the head, quality of life, anxiety and depression. Data will be collected at baseline, after six months and one year by an independent blind assessor just prior to botulinum toxin injections. For the cost effectiveness, an additional economic evaluation will be performed with the costs per quality adjusted life-year as primary outcome parameter.

Discussion

Our study will provide new evidence regarding the (cost-) effectiveness of a standardized, tailored physical therapy program for patients with cervical dystonia. It is widely felt that allied health interventions, including physical therapy, may offer a valuable supplement to the current therapeutic options. A positive outcome will lead to a greater use of the standardized physical therapy program. For the Dutch situation a positive outcome implies that the standardized physical therapy program forms the basis for a national treatment guideline for cervical dystonia.

Trial registration

Number Dutch Trial registration (Nederlands Trial Register): NTR3437

The focal dystonias: current views and challenges for future research

The most common forms of dystonia are those that develop in adults and affect a relatively isolated region of the body. Although these adult-onset focal dystonias are most prevalent, knowledge of their etiologies and pathogenesis has lagged behind some of the rarer generalized dystonias, in which the identification of genetic defects has facilitated both basic and clinical research. This summary provides a brief review of the clinical manifestations of the adult-onset focal dystonias, focusing attention on less well understood clinical manifestations that need further study. It also provides a simple conceptual model for the similarities and differences among the different adult-onset focal dystonias as a rationale for lumping them together as a class of disorders while at the same time splitting them into subtypes. The concluding section outlines some of the most important research questions for the future. Answers to these questions are critical for advancing our understanding of this group of disorders and for developing novel therapeutics.

EMG-based visual-haptic biofeedback: a tool to improve motor control in children with primary dystonia

New insights suggest that dystonic motor impairments could also involve a deficit of sensory processing. In this framework, biofeedback, making covert physiological processes more overt, could be useful. The present work proposes an innovative integrated setup which provides the user with an electromyogram (EMG)-based visual-haptic biofeedback during upper limb movements (spiral tracking tasks), to test if augmented sensory feedbacks can induce motor control improvement in patients with primary dystonia. The ad hoc developed real-time control algorithm synchronizes the haptic loop with the EMG reading; the brachioradialis EMG values were used to modify visual and haptic features of the interface: the higher was the EMG level, the higher was the virtual table friction and the background color proportionally moved from green to red. From recordings on dystonic and healthy subjects, statistical results showed that biofeedback has a significant impact, correlated with the local impairment, on the dystonic muscular control. These tests pointed out the effectiveness of biofeedback paradigms in gaining a better specific-muscle voluntary motor control. The flexible tool developed here shows promising prospects of clinical applications and sensorimotor rehabilitation.

Error-enhancing robot therapy to induce motor control improvement in childhood onset primary dystonia

BACKGROUND

Robot-generated deviating forces during multijoint reaching movements have been applied to investigate motor control and to tune neuromotor adaptation. Can the application of force to limbs improve motor learning? In this framework, the response to altered dynamic environments of children affected by primary dystonia has never been studied.

METHODS

As preliminary pilot study, eleven children with primary dystonia and eleven age-matched healthy control subjects were asked to perform upper limb movements, triangle-reaching (three directions) and circle-writing, using a haptic robot interacting with ad-hoc developed task-specific visual interfaces. Three dynamic conditions were provided, null additive external force (A), constant disturbing force (B) and deactivation of the additive external force again (C). The path length for each trial was computed, from the recorded position data and interaction events.

RESULTS

The results show that the disturbing force affects significantly the movement outcomes in healthy but not in dystonic subjects, already compromised in the reference condition: the external alteration uncalibrates the healthy sensorimotor system, while the dystonic one is already strongly uncalibrated. The lack of systematic compensation for perturbation effects during B condition is reflected into the absence of after-effects in C condition, which would be the evidence that CNS generates a prediction of the perturbing forces using an internal model of the environment.The most promising finding is that in dystonic population the altered dynamic exposure seems to induce a subsequent improvement, i.e. a beneficial after-effect in terms of optimal path control, compared with the correspondent reference movement outcome.

CONCLUSIONS

The short-time error-enhancing training in dystonia could represent an effective approach for motor performance improvement, since the exposure to controlled dynamic alterations induces a refining of the existing but strongly imprecise motor scheme and sensorimotor patterns.

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.

Prevalence, predictors, and perceived effectiveness of complementary, alternative and integrative medicine in adult-onset primary dystonia

BACKGROUND

Complementary and Alternative Medicine (CAM) use is on the rise in both the US and Europe, despite questions about its safety and effectiveness, and lack of national standards. We aimed to determine the prevalence and predictors of CAM and integrative medicine use (CAM-I) and perceived effectiveness compared to the standard treatment of botulinum toxin injections in patients with adult-onset primary dystonia.

METHODS

This was a retrospective questionnaire study of 389 dystonia patients examining the effects age, gender, education level and number of affected anatomical regions on botulinum toxin and CAM-I use and their perceived effectiveness.

RESULTS

53% (208) of patients reported CAM-I use, while 90% (349) used the standard treatment (botulinum toxin), and 48% used both. Education was the only significant predictor of CAM-I use - individuals with bachelor's degrees were more likely to try CAM-I whereas those with high school diplomas were less likely. The mean effectiveness rate for botulinum toxin injections (59%) significantly exceeded that for CAM-I (28%, p < 0.0001).

CONCLUSIONS

Our work highlights the need for scientifically sound studies to determine the safety, effectiveness and expense of CAM-I treatments for dystonia and other neurological disorders given that CAM-I use is steadily increasing, there is great variability in what is classified as CAM-I, and the effectiveness of some modalities may be significantly less than conventional medical treatments.