History of the ‘geste antagoniste’ sign in cervical dystonia

Function and dysfunction of the dystonia network: an exploration of neural circuits that underlie the acquired and isolated dystonias

Dystonia is a highly prevalent movement disorder that can manifest at any time across the lifespan. An increasing number of investigations have tied this disorder to dysfunction of a broad "dystonia network" encompassing the cerebellum, thalamus, basal ganglia, and cortex. However, pinpointing how dysfunction of the various anatomic components of the network produces the wide variety of dystonia presentations across etiologies remains a difficult problem. In this review, a discussion of functional network findings in non-mendelian etiologies of dystonia is undertaken. Initially acquired etiologies of dystonia and how lesion location leads to alterations in network function are explored, first through an examination of cerebral palsy, in which early brain injury may lead to dystonic/dyskinetic forms of the movement disorder. The discussion of acquired etiologies then continues with an evaluation of the literature covering dystonia resulting from focal lesions followed by the isolated focal dystonias, both idiopathic and task dependent. Next, how the dystonia network responds to therapeutic interventions, from the "geste antagoniste" or "sensory trick" to botulinum toxin and deep brain stimulation, is covered with an eye towards finding similarities in network responses with effective treatment. Finally, an examination of how focal network disruptions in mouse models has informed our understanding of the circuits involved in dystonia is provided. Together, this article aims to offer a synthesis of the literature examining dystonia from the perspective of brain networks and it provides grounding for the perspective of dystonia as disorder of network function.

Isolated Cervical Dystonia: Diagnosis and Classification

This document presents a consensus on the diagnosis and classification of isolated cervical dystonia (iCD) with a review of proposed terminology. The International Parkinson and Movement Disorder Society Dystonia Study Group convened a panel of experts to review the main clinical and diagnostic issues related to iCD and to arrive at a consensus on diagnostic criteria and classification. These criteria are intended for use in clinical research, but also may be used to guide clinical practice. The benchmark is expert clinical observation and evaluation. The criteria aim to systematize the use of terminology as well as the diagnostic process, to make it reproducible across centers and applicable by expert and non-expert clinicians. Although motor abnormalities remain central, increasing recognition has been given to nonmotor manifestations, which are incorporated into the current criteria. Three iCD presentations are described in some detail: idiopathic (focal or segmental) iCD, genetic iCD, and acquired iCD. The relationship between iCD and isolated head tremor is also reviewed. Recognition of idiopathic iCD has two levels of certainty, definite or probable, supported by specific diagnostic criteria. Although a probable diagnosis is appropriate for clinical practice, a higher diagnostic level may be required for specific research studies. The consensus retains elements proven valuable in previous criteria and omits aspects that are no longer justified, thereby encapsulating diagnosis according to current knowledge. As understanding of iCD expands, these criteria will need continuous revision to accommodate new advances. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Treatment of strabismus and blepharospasm with Botox (onabotulinumtoxinA): Development, insights, and impact

Strabismus, deviation of the ocular alignment, can adversely affect quality of life and activities of daily living. Surgery was the prior standard of care for strabismus, but up to 40% of patients required additional surgeries. This need for more effective and less invasive treatment, along with the convergence of other events such as the development of electromyography, purification of botulinum toxin A, and the finding that injection of botulinum toxin type A could paralyze the hind limbs of chicks, led Dr. Alan Scott to investigate injection of his formulation for strabismus. The positive results of initial trials in monkeys segued to human trials with observations of alignment improvements and few adverse events. The success of botulinum toxin type A in the treatment of strabismus led to interest in its use to treat other skeletal muscles, particularly in blepharospasm, a type of focal dystonia involving eyelid spasms and involuntary eye closure that lacked an effective pharmacological treatment. Patient groups helped to increase awareness of this novel treatment, and results from clinical trials confirmed its effectiveness. Dr. Scott's formulation, then known as Oculinum, received its first Food and Drug Administration approvals in 1989 for strabismus and blepharospasm. Allergan acquired Oculinum in 1991, renaming it Botox. These initial uses led to its application in a myriad of other indications as outlined in other articles of this supplement.

Neuromodulation in Dystonia - Harnessing the Network

Adult-onset isolated focal dystonia (AOIFD) is a network disorder characterised by abnormalities of sensory processing and motor control. These network abnormalities give rise to both the phenomenology of dystonia and the epiphenomena of altered plasticity and loss of intracortical inhibition. Existing modalities of deep brain stimulation effectively modulate parts of this network but are limited both in terms of targets and invasiveness. Novel approaches using a variety of non-invasive neuromodulation techniques including transcranial stimulation and peripheral stimulation present an interesting alternative approach and may, in conjunction with rehabilitative strategies, have a role in tailored therapies targeting the underlying network abnormality behind AOIFD.

Direct cerebello-striatal loop in dystonia as a possible new target for deep brain stimulation: A revised view of subcortical pathways involved

Dystonia is the second most common movement disorder next to tremor, but its pathophysiology remains unsettled. Its therapeutic measures include anti-cholingerics and other medications, in addition to botulinum neurotoxin injections, and stereotaxic surgery including deep brain stimulation (DBS), but there still remain a number of patients resistant to the therapy. Evidence has been accumulating suggesting that basal ganglia in association with the cerebellum are playing a pivotal role in pathogenesis. Clinical observations such as sensory tricks and the effects of muscle afferent stimulation and blockage suggest the conflict between the cortical voluntary motor plan and the subcortical motor program or motor subroutine controlling the intended action semi-automatically. In this review, the current understanding of the possible pathways or loops involved in dystonia is presented, and we review promising new targets for Deep Brain Stimulation (DBS) including the cerebellum.

‘Tricked’ sensory trick: a geste antagoniste in functional dystonia

A sensory trick, or geste antagoniste, is a manoeuvre used by patients with dystonia to ameliorate their dystonic movements or posturing. Typically, a sensory trick is a confirmatory clue indicating an organic nature of the dystonia. In this report, we present an extremely rare case of a sensory trick in a patient with functional 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.

Muscle Tone Physiology and Abnormalities

The simple definition of tone as the resistance to passive stretch is physiologically a complex interlaced network encompassing neural circuits in the brain, spinal cord, and muscle spindle. Disorders of muscle tone can arise from dysfunction in these pathways and manifest as hypertonia or hypotonia. The loss of supraspinal control mechanisms gives rise to hypertonia, resulting in spasticity or rigidity. On the other hand, dystonia and paratonia also manifest as abnormalities of muscle tone, but arise more due to the network dysfunction between the basal ganglia and the thalamo-cerebello-cortical connections. In this review, we have discussed the normal homeostatic mechanisms maintaining tone and the pathophysiology of spasticity and rigidity with its anatomical correlates. Thereafter, we have also highlighted the phenomenon of network dysfunction, cortical disinhibition, and neuroplastic alterations giving rise to dystonia and paratonia.

Pallidal deep brain stimulation in primary Meige syndrome: clinical outcomes and psychiatric features

OBJECTIVES

To study the efficacy and safety of bilateral globus pallidus internus deep brain stimulation (GPi-DBS) in refractory Meige syndrome (MS) and evaluate the psychiatric disorders before and after surgery.

METHODS

Twenty-two patients with MS treated with bilateral GPi-DBS were retrospectively analysed before surgery and after continuous neurostimulation. Before surgery, patients were assessed by the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS), Self-Rating Depression Scale, Medical Outcomes Study 36-Item Short-Form General Health Survey (SF-36) and Pittsburgh Sleep Quality Index (PQSI), which corresponded to motor symptoms, depressive state, quality of life and sleep quality, respectively. The implantable pulse generator of each patient was activated at 1 month after surgery. At 1 month, 3 months, 6 months and 12 months after continuous neurostimulation, all patients were evaluated by the same scales above.

RESULTS

The BFMDRS movement scores decreased from 15.0±5.3 before surgery to 3.5±4.5 at 12 months after neurostimulation, with a mean improvement of 78% (p<0.001). The BFMDRS disability scores improved from 7.4±4.9 before surgery to 4.0±4.6 at 12 months after neurostimulation, with a mean improvement of 56% (p<0.001). The postoperative SF-36 scores had the remarkable improvement compared with baseline scores. Impaired sleep quality was found in 82% of patients and depression in 64% before surgery, which didn't neither obtained amelioration after continuous neurostimulation.

CONCLUSIONS

Bilateral pallidal neurostimulation is a beneficial therapeutic option for refractory MS, which could improve the motor symptoms except for depression and sleep quality.

It's tricky: Rating alleviating maneuvers in cervical dystonia

OBJECTIVES

To investigate hypothesized sources of error when quantifying the effect of the sensory trick in cervical dystonia (CD) with the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS-2), test strategies to mitigate them, and provide guidance for future research on the sensory trick.

METHODS

Previous analyses suggested the sensory trick (or "alleviating maneuver", AM) item be removed from the TWSTRS-2 because of its poor clinimetric properties. We hypothesized three sources of clinimetric weakness for rating the AM: 1) whether patients were given sufficient time to demonstrate their AM; 2) whether patients' CD was sufficiently severe for detecting AM efficacy; and 3) whether raters were inadvertently rating the item in reverse of scale instructions. We tested these hypotheses with video recordings and TWSTRS-2 ratings by one "site rater" and a panel of five "video raters" for each of 185 Dystonia Coalition patients with isolated CD.

RESULTS

Of 185 patients, 23 (12%) were not permitted sufficient testing time to exhibit an AM, 23 (12%) had baseline CD too mild to allow confident rating of AM effect, and 1 site- and 1 video-rater each rated the AM item with a reverse scoring convention. When these confounds were eliminated in step-wise fashion, the item's clinimetric properties improved.

CONCLUSIONS

The AM's efficacy can contribute to measuring CD motor severity by addressing identified sources of error during its assessment and rating. Given the AM's sensitive diagnostic and potential pathophysiologic significance, we also provide guidance on modifications to how AMs can be assessed in future CD research.

Oral appliances in the treatment of oromandibular dystonia: a systematic review

Oromandibular dystonia (OMD) is a clinically and etiologically heterogeneous form of focal dystonia with variable social and functional implications. The results of pharmacological treatment and botulinum toxin infiltrations are often unsatisfactory. We performed a systematic review on the effects of oral and dental appliances in patients with OMD. Most of the reports in the literature are single subject descriptions or small case series with a considerable variability in the type of dystonia, the type of evaluated appliances and in the outcome measures. Only one report included a large group of unselected patients that were evaluated with a mixture of outcome measures. Although it appears that a number of OMD patients, especially those who benefit from sensory tricks, may sustain some improvement with the use of oral appliances, no definitive conclusions can be drawn about the type of patients that may benefit, nor about the preferred type or mode of appliance. More research in this field is needed, using standardized approaches and clearly defined outcome measures in larger cohorts of OMD patients that are clinically and diagnostically well characterized.

Laryngeal vibration as a non-invasive neuromodulation therapy for spasmodic dysphonia

Spasmodic dysphonia (SD) is an incurable focal dystonia of the larynx that impairs speech and communication. Vibro-tactile stimulation (VTS) alters afferent proprioceptive input to sensorimotor cortex that controls speech. This proof-of-concept study examined the effect of laryngeal VTS on speech quality and cortical activity in 13 SD participants who vocalized the vowel /a/ while receiving VTS for 29 minutes. In response to VTS, 9 participants (69%) exhibited a reduction of voice breaks and/or a meaningful increase in smoothed cepstral peak prominence, an acoustic measure of voice/speech quality. Symptom improvements persisted for 20 minutes past VTS. Application of VTS induced a significant suppression of theta band power over the left somatosensory-motor cortex and a significant rise of gamma rhythm over right somatosensory-motor cortex. Such suppression of theta oscillations is observed in patients with cervical dystonia who apply effective sensory tricks, suggesting that VTS in SD may activate a similar neurophysiological mechanism. Results of this feasibility study indicate that laryngeal VTS modulates neuronal synchronization over sensorimotor cortex, which can induce short-term improvements in voice quality. The effects of long-term VTS and its optimal dosage for treating voice symptoms in SD are still unknown and require further systematic study.

Édouard Brissaud: distinguished neurologist and Charcot's pupil

Professor Charcot had several pupils in his famous neurological service at the Salpêtrière Hospital in Paris, France. Among them, Édouard Brissaud was one of Charcot's favorite pupils, temporarily becoming his successor after Charcot's death. Brissaud's neurological contributions were significant, including the description of hemifacial spasm, "geste antagoniste" in dystonia, pseudobulbar affect, post-traumatic stress disorder, the Brissaud-Sicard syndrome, and Brissaud's sign. Additionally, Brissaud was the first to suggest that Parkinson's disease pathology could be related to the substantia nigra.

Disrupted superior collicular activity may reveal cervical dystonia disease pathomechanisms

Cervical dystonia is a common neurological movement disorder characterised by muscle contractions causing abnormal movements and postures affecting the head and neck. The neural networks underpinning this condition are incompletely understood. While animal models suggest a role for the superior colliculus in its pathophysiology, this link has yet to be established in humans. The present experiment was designed to test the hypothesis that disrupted superior collicular processing is evident in affected patients and in relatives harbouring a disease-specific endophenotype (abnormal temporal discrimination). The study participants were 16 cervical dystonia patients, 16 unaffected first-degree relatives with abnormal temporal discrimination, 16 unaffected first-degree relatives with normal temporal discrimination and 16 healthy controls. The response of participant’s superior colliculi to looming stimuli was assessed by functional magnetic resonance imaging. Cervical dystonia patients and relatives with abnormal temporal discrimination demonstrated (i) significantly reduced superior collicular activation for whole brain and region of interest analysis; (ii) a statistically significant negative correlation between temporal discrimination threshold and superior collicular peak values. Our results support the hypothesis that disrupted superior collicular processing is involved in the pathogenesis of cervical dystonia. These findings, which align with animal models of cervical dystonia, shed new light on pathomechanisms in humans.

The clinical phenomenology and associations of trick maneuvers in cervical dystonia

Sensory trick is an unusual clinical feature in cervical dystonia that attenuates disease symptoms by slight touch to a specific area of the face or head. Using a semi-quantitative questionnaire-based study of 197 patients with idiopathic cervical dystonia, we sought to determine probable pathophysiologic correlates, with the wider aim of examining its eventual clinical significance. The typical sensory trick, i.e., light touch, not necessitating the use of force leading to simple overpowering of dystonic activity, was present in 83 (42.1 %) patients. The vast majority of the patients required a specific sequence of sensorimotor inputs, including touch sensation on the face or different areas of the head, and also sensory and motor input of the hand itself. Deviations often led to a significant decrease in effectiveness and lack of expected benefit. Moreover, patients able to perform the maneuver reported compellingly higher subjective effect of botulinum toxin treatment (median 7 vs. 5 on a scale of 0-10; p < 0.0001) and lower depression score (median 10 vs. 14 on the Montgomery Åsberg Depression Rating scale; p < 0.001). Overall, the results point to marked disruption of sensorimotor networks in cervical dystonia. The mechanism of the sensory trick action may be associated with balancing the abnormal activation patterns by specific sensorimotor inputs. Its presence may be considered a positive predictive factor for responsiveness to botulinum toxin treatment.

Early Illustrations of Geste Antagoniste in Cervical and Generalized Dystonia

Background

Geste antagoniste, or sensory trick, is a voluntary maneuver that temporarily reduces the severity of dystonic postures or movements. We present a historical review of early reports and illustrations of geste antagoniste.

Results

In 1894, Brissaud described this phenomenon in Paris in patients with torticollis. He noted that a violent muscular contraction could be reversed by a minor voluntary action. He considered the improvement obtained by what he called “simple mannerisms, childish behaviour or fake pathological movements” was proof of the psychogenic origin of what he named mental torticollis. This concept was supported by photographical illustrations of the patients. The term geste antagoniste was used by Brissaud’s pupils, Meige and Feindel, in their 1902 monograph on movement disorders. Other reports and illustrations of this sign were published in Europe between 1894 and 1906. Although not mentioned explicitly, geste antagoniste was also illustrated in a case report of generalized dystonia in Oppenheim’s 1911 seminal description of dystonia musculorum deformans in Berlin.

Discussion

Brissaud-Meige’s misinterpretation of the geste antagoniste unfortunately anchored the psychogenic origin of dystonia for decades. In New York, Herz brought dystonia back into the realm of organic neurology in 1944. Thereafter, it was given prominence by other authors, notably Fahn and Marsden in the 1970–1980s. Nowadays, neurologists routinely investigate for geste antagoniste when a dystonic syndrome is suspected, because it provides a further argument in favor of dystonia. The term alleviating maneuver was proposed in 2014 to replace sensory trick or geste antagoniste. This major sign is now part of the motor phenomenology of the 2013 Movement Disorder Society’s classification of dystonia.

Utilizing the concept of geste antagoniste for conservative management of oro-mandibular tardive dyskinesia: a case report and mini-review

OBJECTIVE

This case report highlights the implication of the concept of "geste antagoniste" in conservatively managing oromotor dysfunction and its complications.

CLINICAL PRESENTATION

A 66-year-old female with a 1-year history of tardive dyskinesia (TD) was referred to the Craniofacial Pain Department (CPC) at Tufts University School of Dental Medicine for management of sore labial/lingual mucosa secondary to excessive daytime involuntary activity of the tongue, lips, and mandible. A detailed head/neck examination revealed excessive involuntary movements of the tongue, lips, and mandible with generalized tenderness of her masticatory muscles. No TMJ or bone pathology was evident in a panoramic radiograph.

INTERVENTION

A lower daytime appliance with bilateral posterior contacts was fabricated to protect her oral mucosa. On reevaluation, excessive movement of the jaw/tongue was significantly reduced with the presence of the appliance in her mouth. Face/neck muscle tenderness was also greatly reduced.

CONCLUSION

The use of oral appliance therapy in TD patients plays an important role in protecting the teeth/oral mucosa. The subsequent inhibition of excessive motor activity is proposed and should be further investigated.

Using voluntary motor commands to inhibit involuntary arm movements

A hallmark of voluntary motor control is the ability to stop an ongoing movement. Is voluntary motor inhibition a general neural mechanism that can be focused on any movement, including involuntary movements, or is it mere termination of a positive voluntary motor command? The involuntary arm lift, or 'floating arm trick', is a distinctive long-lasting reflex of the deltoid muscle. We investigated how a voluntary motor network inhibits this form of involuntary motor control. Transcranial magnetic stimulation of the motor cortex during the floating arm trick produced a silent period in the reflexively contracting deltoid muscle, followed by a rebound of muscle activity. This pattern suggests a persistent generator of involuntary motor commands. Instructions to bring the arm down voluntarily reduced activity of deltoid muscle. When this voluntary effort was withdrawn, the involuntary arm lift resumed. Further, voluntary motor inhibition produced a strange illusion of physical resistance to bringing the arm down, as if ongoing involuntarily generated commands were located in a 'sensory blind-spot', inaccessible to conscious perception. Our results suggest that voluntary motor inhibition may be a specific neural function, distinct from absence of positive voluntary motor commands.

Impaired Limb Proprioception in Adults With Spasmodic Dysphonia

OBJECTIVES

Focal dystonia of the head and neck are associated with a loss of kinesthetic acuity at muscles distant from the dystonic sites. That is, while the motor deficits in focal dystonia are confined, the associated somatosensory deficits are generalized. This is the first systematic study to examine, if patients diagnosed with spasmodic dystonia (SD) show somatosensory impairments similar in scope to other forms of focal dystonia.

METHODS

Proprioceptive acuity (ability to discriminate between two stimuli) for forearm position and motion sense was assessed in 14 spasmodic dystonia subjects and 28 age-matched controls using a passive motion apparatus. Psychophysical thresholds, uncertainty area (UA), and a proprioceptive acuity index (AI) were computed based on the subjects' verbal responses.

RESULTS

The main findings are as follows: first, the SD group showed significantly elevated thresholds and UAs for forearm position sense compared with the control group. Second, 9 of 14 dystonia subjects (64%) exhibited an AI for position sense above the control group maximum. Three SD subjects had a motion sense AI above the control group maximum.

CONCLUSIONS

The results indicate that impaired limb proprioception is a common feature of SD. Like other forms of focal dystonia, spasmodic dystonia does affect the somatosensation of nondystonic muscle systems. That is, SD is associated with a generalized somatosensory deficit.

"Closing the loop" in cervical dystonia: a new clinical phenomenon

BACKGROUND

The sensory trick or geste antagoniste is a cardinal feature of cervical dystonia. Patients are often aware of their tricks, using them to their advantage to temporarily improve dystonic symptoms. The typical sensory trick must be internally generated by the patient in order to be effective, and external mechanical pressure alone may not be sufficient.

METHODS

We present a case description. We present and demonstrate a new clinical phenomenon in patients with cervical dystonia, which we call "closing the loop".

DISCUSSION

We discuss the possible mechanisms underlying this finding.

Tricks in dystonia: ordering the complexity

Sensory tricks are various manoeuvres that can ameliorate dystonia. Common characteristics are well known, but their variety is wide, sensory stimulation is not necessarily the critical feature, and their physiology is unknown. To enumerate the various forms of sensory tricks and describe their nature, research findings and theories that may elucidate their neurophysiologic mechanism, we reviewed the literature pertaining to sensory tricks, including variants like motor tricks, imaginary tricks, forcible tricks and reverse sensory tricks. On the basis of this information, we propose a new classification of sensory tricks to include its variants. We highlight neurophysiologic evidence suggesting that sensory tricks work by decreasing abnormal facilitation. We tie this with established dystonia pathogenesis and postulate that sensory tricks decrease abnormally increased facilitation to inhibition ratios in the dystonic brain. It appears worthwhile for patients to search for possible sensory tricks.

Alleviating manoeuvres (sensory tricks) in cervical dystonia

BACKGROUND

There is limited information on the phenomenology, clinical characteristics and pathophysiology of alleviating manoeuvres (AM), also called 'sensory tricks' in cervical dystonia (CD).

METHODS

Individual data, collected from 10 sites participating in the Dystonia Coalition (http://clinicaltrials.gov/show/NCT01373424), included description of localisation and phenomenology of AM collected by systematic review of standardised video examinations. Analyses correlated demographic, neurologic, and psychiatric features of CD patients with or without effective AM.

RESULTS

Of 154 people studied, 138 (89.6%) used AM, of which 60 (43.4%) reported partial improvement, 55 (39.8%) marked improvement, and 4 (0.03%) no effect on dystonic posture. Light touch, usually to the lower face or neck, was used by >90%. The presence or location of AM did not correlate with the severity of the dystonia.

CONCLUSIONS

In this large and comprehensive study of CD, we found no clinical predictors of effective AM. Further studies of sensorimotor integration in dystonia are needed to better understand the pathophysiology of AM.

Spinal stimulation for movement disorders

Epidural spinal cord stimulation (SCS) is currently proposed to treat intractable neuropathic pain. Since the 1970s, isolated cases and small cohorts of patients suffering from dystonia, tremor, painful leg and moving toes (PLMT), or Parkinson’s disease were also treated with SCS in the context of exploratory clinical studies. Despite the safety profile of SCS observed in these various types of movement disorders, the degree of improvement of abnormal movements following SCS has been heterogeneous among patients and across centers in open-label trials, stressing the need for larger, randomized, double-blind studies. This article provides a comprehensive review of both experimental and clinical studies of SCS application in movement disorders.

Sensory aspects of movement disorders

Movement disorders, which include disorders such as Parkinson's disease, dystonia, Tourette's syndrome, restless legs syndrome, and akathisia, have traditionally been considered to be disorders of impaired motor control resulting predominantly from dysfunction of the basal ganglia. This notion has been revised largely because of increasing recognition of associated behavioural, psychiatric, autonomic, and other non-motor symptoms. The sensory aspects of movement disorders include intrinsic sensory abnormalities and the effects of external sensory input on the underlying motor abnormality. The basal ganglia, cerebellum, thalamus, and their connections, coupled with altered sensory input, seem to play a key part in abnormal sensorimotor integration. However, more investigation into the phenomenology and physiological basis of sensory abnormalities, and about the role of the basal ganglia, cerebellum, and related structures in somatosensory processing, and its effect on motor control, is needed.

Chiropractic care using a functional neurologic approach for idiopathic cervical dystonia in a 59-year-old woman

OBJECTIVE

The purpose of this case report is to describe the care and outcomes of a patient with cervical dystonia who was treated using chiropractic and other alternative medicine interventions.

CLINICAL FEATURES

A 59-year-old woman had an 11-year history of cervical dystonia. She had an uncontrollable 60° leftward head rotation upon shutting her eyes and had spasmodic contractions that caused fatigue.

INTERVENTION AND OUTCOME

The management consisted of blue-lensed glasses, vibration stimulation, spinal manipulation, and eye-movement exercises. Within the first week of treatment, she had a reduction in symptoms, which was documented using a functional numeric scale, and improved posture, which was assessed using measurements from her midsternal line to the center of her chin.

CONCLUSION

This patient with cervical dystonia responded to the use of conservative, nonpharmacological treatment procedures that consisted of chiropractic care using a functional neurologic approach aimed at improving her spasmodic contractions and function.

Samuel Alexander Kinnier Wilson. Wilson's disease, Queen Square and neurology

This historical article describes the life and work of the British physician Samuel Alexander Kinnier Wilson (1878-1937), who was one of the world's greatest neurologists of the first half of the 20th century. Early in his career, Wilson spent one year in Paris in 1903 where he learned from Pierre-Marie at Bicêtre Hospital. He subsequently retained uninterrupted links with French neurology. He also visited in Leipzig the German anatomist Paul Flechsig. In 1904, Wilson returned to London, where he worked for the rest of his life at the National Hospital for the Paralysed and Epileptic (later the National Hospital for Nervous Diseases, and today the National Hospital for Neurology and Neurosurgery) in Queen Square, and also at Kings' College Hospital. He wrote on 'the old motor system and the new', on disorders of motility and muscle tone, on the epilepsies, on aphasia, apraxia, tics, and pathologic laughing and crying, and most importantly on Wilson's disease. The other objective of our paper is to commemorate the centenary of Wilson's most important work published in 1912 in Brain, and also in Revue Neurologique, on an illness newly recognized and characterized by him entitled "Progressive lenticular degeneration, a familial nervous disease associated with liver cirrhosis". He analyzed 12 clinical cases, four of whom he followed himself, but also four cases previously published by others and a further two that he considered in retrospect had the same disease as he was describing. The pathological profile combined necrotic damage in the lenticular nuclei of the brain and hepatic cirrhosis. This major original work is summarized and discussed in the present paper. Wilson not only delineated what was later called hepato-lenticular degeneration and Wilson's disease, but also introduced for the first time the terms extrapyramidal syndrome and extrapyramidal system, stressing the role of the basal ganglia in motility. The present historical work emphasizes the special contributions made by Wilson to the study of movement disorders, including akinesia and bradykinesia in Parkinson's disease, and their relation to basal ganglia pathology.

Focal dystonia in musicians: linking motor symptoms to somatosensory dysfunction

Musician's dystonia (MD) is a neurological motor disorder characterized by involuntary contractions of those muscles involved in the play of a musical instrument. It is task-specific and initially only impairs the voluntary control of highly practiced musical motor skills. MD can lead to a severe decrement in a musician's ability to perform. While the etiology and the neurological pathomechanism of the disease remain unknown, it is known that MD like others forms of focal dystonia is associated with somatosensory deficits, specifically a decreased precision of tactile and proprioceptive perception. The sensory component of the disease becomes also evident by the patients' use of “sensory tricks” such as touching dystonic muscles to alleviate motor symptoms. The central premise of this paper is that the motor symptoms of MD have a somatosensory origin and are not fully explained as a problem of motor execution. We outline how altered proprioceptive feedback ultimately leads to a loss of voluntary motor control and propose two scenarios that explain why sensory tricks are effective. They are effective, because the sensorimotor system either recruits neural resources normally involved in tactile-proprioceptive (sensory) integration, or utilizes a fully functioning motor efference copy mechanism to align experienced with expected sensory feedback. We argue that an enhanced understanding of how a primary sensory deficit interacts with mechanisms of sensorimotor integration in MD provides helpful insights for the design of more effective behavioral therapies.