Stereotactic Thalamotomy for Hairdresser's Dystonia: A Case Series

Successful treatment of focal hand dystonia after cervical whiplash injury by thalamotomy

Background:

Posttraumatic focal hand dystonia after cervical whiplash injury is rare. Moreover, the treatment of peripheral posttraumatic dystonia is usually ineffective. Herein, we report a case of successful thalamotomy for a patient with focal hand dystonia after cervical whiplash injury.

Case Description:

A 39-year-old woman was hit from behind by a car; subsequently, she felt strange in the right hand and was diagnosed with whiplash injury. A month later, she developed a persistent abnormal posture of the right hand. Brain imaging showed no lesions, and cervical magnetic resonance imaging showed stenosis but no spinal cord signal changes. Posttraumatic dystonia was diagnosed, for which the patient underwent left ventro-oral (Vo) thalamotomy. One year after the first surgery, the patient underwent left Vo and ventral intermediate nucleus (Vim) thalamotomy due to recurrence of dystonia. Nine years after the second surgery, the patient continues to be able to maintain her normal physical routine.

Conclusion:

Vo-Vim thalamotomy may be a feasible and effective treatment for focal hand dystonia after cervical whiplash injury.

Treatment of focal hand dystonia: current status

BACKGROUND

Focal hand dystonia (FHD) is usually adult-onset focal dystonia that can be associated with marked occupational and functional disability leading to reduced quality of life.

METHODS

Relevant studies on treatment options for FHD, their limitations, and current recommendations were reviewed using the PubMed search until March 31, 2021. Besides, the reference lists of the retrieved publications were manually searched to explore other relevant studies.

RESULTS

and conclusion Currently, botulinum toxin has the best evidence for treatment of FHD, and 20-90% of patients experience symptomatic improvement. However, its benefit is often limited by the reduction of muscle tonus acting on the muscle spindle. Different surgical modalities that have been used to treat focal hand dystonia include lesional surgery, deep brain stimulation, and magnetic resonance-guided focused ultrasound thalamotomy. Recent studies exploring the role of behavioral techniques, sensorimotor training, and neuromodulation for the treatment of focal hand dystonia have reported good outcomes, but larger studies are required before implementing these interventions in practice.

Dystonia and Cerebellum: From Bench to Bedside

Dystonia pathogenesis remains unclear; however, findings from basic and clinical research suggest the importance of the interaction between the basal ganglia and cerebellum. After the discovery of disynaptic pathways between the two, much attention has been paid to the cerebellum. Basic research using various dystonia rodent models and clinical studies in dystonia patients continues to provide new pieces of knowledge regarding the role of the cerebellum in dystonia genesis. Herein, we review basic and clinical articles related to dystonia focusing on the cerebellum, and clarify the current understanding of the role of the cerebellum in dystonia pathogenesis. Given the recent evidence providing new hypotheses regarding dystonia pathogenesis, we discuss how the current evidence answers the unsolved clinical questions.

Improvement of Writer's Cramp from an Old Lesion in the Contralateral Hemisphere with Transient Gait Disturbance After Thalamotomy

BACKGROUND

Stereotactic ventro-oral thalamotomy has been performed in cases of focal task-specific dystonia, including writer's cramp, with excellent outcomes. However, no reports have revealed the outcome of ventro-oral thalamotomy in a patient with a contralateral cerebral lesion. We describe a patient with left-hand writer's cramp with an old lesion in the left hemisphere and transient gait disturbance after right ventro-oral thalamotomy.

CASE DESCRIPTION

A 43-year-old man had a hemorrhage in the left basal ganglia due to cerebral arteriovenous malformation at 22 years of age, and right hemiparesis remained as a sequela. He developed left-handed writing ability; however, he became aware of the stiffness of his left hand and difficulty in writing. Writer's cramp was diagnosed. Medical treatments were not effective, and right ventro-oral thalamotomy was performed. Although his writing ability improved, he could not walk. After performing rehabilitation, his walking completely improved, reaching the level before surgery, after 3 months, and his writer's cramp was completely cured.

CONCLUSIONS

In patients with basal nucleus lesions, gait disturbance may appear transiently after contralateral thalamotomy. It is crucial to fully explain the potential complications, particularly in relation to temporal gait disturbances, and obtain informed consent.

Safety and long-term efficacy of ventro-oral thalamotomy for focal hand dystonia: A retrospective study of 171 patients

Objective

To report the safety and long-term efficacy of ventro-oral thalamotomy for 171 consecutive patients with task-specific focal hand dystonia.

Methods

Between October 2003 and February 2017, 171 consecutive patients with task-specific focal hand dystonia underwent unilateral ventro-oral thalamotomy. Etiologies included writer's cramps (n = 92), musician's dystonias (n = 58), and other occupational task-related dystonias (n = 21). The task-specific focal hand dystonia scale was used to evaluate patients' neurologic conditions (range 1–5, high score indicated a better condition). The scores before surgery; at 1 week, 3 months, and 12 months postoperatively; and the last available follow-up period were determined. Postoperative complications and postoperative recurrence were also evaluated.

Results

The scores before surgery; at 1 week (1.72 ± 0.57, 4.33 ± 0.85 [p < 0.001]), 3 months (4.30 ± 1.06 [p < 0.001]), and 12 months (4.30 ± 1.13 [p < 0.001]); and the last available follow-up (4.39 ± 1.07 [p < 0.001]) postoperatively improved. The mean clinical follow-up period was 25.4 ± 32.1 months (range: 3–165). Permanent adverse events developed in 6 patients (3.5%). Eighteen patients developed recurrent dystonic symptoms postoperatively. Of these 18 patients, 9 underwent ventro-oral thalamotomy again, of which 7 achieved improvement.

Conclusion

Ventro-oral thalamotomy is a feasible and reasonable treatment for patients with refractory task-specific focal hand dystonias. Prospective, randomized, and blinded studies are warranted to clarify more accurate assessment of the safety and efficacy of ventro-oral thalamotomy for task-specific focal hand dystonia.

Classification of evidence

This study provides Class IV evidence that for patients with task-specific focal hand dystonia, ventro-oral thalamotomy improves dystonia.

Surgical treatment of dystonia

INTRODUCTION

Treatment of dystonia should be individualized and tailored to the specific needs of patients. Surgical treatment is an important option in medically refractory cases. Several issues regarding type of the surgical intervention, targets, and predict factors of benefit are still under debate. Areas covered: To date, several clinical trials have proven the benefit and safety of deep brain stimulation (DBS) for inherited and idiopathic isolated dystonia, whereas there is still insufficient evidence in combined and acquired dystonia. The globus pallidus internus (GPi) is the target with the best evidence, but data on the subthalamic nucleus seems also to be promising. Evidence suggests that younger patients with shorter disease duration experience greater benefit following DBS. Pallidotomy and thalamotomy are currently used in subset of carefully selected patients. The development of MRI-guided focused ultrasound might bring new options to ablation approach in dystonia. Expert commentary: GPi-DBS is effective and safe in isolated dystonia and should not be delayed when symptoms compromise quality of life and functionality. Identifying the best candidates to surgery on acquired and combined dystonias is still necessary. New insights about pathophysiology of dystonia and new technological advances will undoubtedly help to tailor surgery and optimize clinical effects.

Full recovery from drummer's dystonia with foot and arm symptoms after stereotactic ventro-oral thalamotomy: a case report

Ventro-oral (Vo) thalamotomy is effective in patients with focal task-specific dystonias (FTSDs), but only in those with upper-limb symptoms. We describe a patient with drummer's dystonia who completely recovered after Vo thalamotomy. A 37-year-old man who started playing drums at 14 began having difficulty performing fine movements with his right foot when drumming at 22. He experienced right hand cramps while drumming 3 months before visiting our hospital. He was diagnosed with FTSD. Left Vo thalamotomy was performed, which led to complete improvement of symptoms. Vo thalamotomy may be effective for FTSD patients with upper- and lower-extremity symptoms.

A unifying motor control framework for task-specific dystonia

Task-specific dystonia is a movement disorder characterized by a painless loss of dexterity specific to a particular motor skill. This disorder is prevalent among writers, musicians, dancers and athletes. No current treatment is predictably effective, and the disorder generally ends the careers of affected individuals. Traditional disease models of dystonia have a number of limitations with regard to task-specific dystonia. We therefore discuss emerging evidence that the disorder has its origins within normal compensatory mechanisms of a healthy motor system in which the representation and reproduction of motor skill are disrupted. We describe how risk factors for task-specific dystonia can be stratified and translated into mechanisms of dysfunctional motor control. The proposed model aims to define new directions for experimental research and stimulate therapeutic advances for this highly disabling disorder.

Occupational Health and the Performing Arts: An Introduction

OBJECTIVE

Workplace hazards in the performing arts cause injuries, disabilities, and deaths every year. Occupational health professionals are familiar with most of these hazards and are particularly qualified to contribute to efforts to reduce them. This article reviews current health issues in the performing arts and highlights opportunities for occupational health contributions.

METHODS

Recognized experts in performing arts medicine were consulted and articles illustrating performing arts health issues were reviewed. Literature sources included medical databases, unindexed art-health publications, and popular press articles.

RESULTS

Resources discussing hazards and health issues in theater, dance, voice, and instrumental musicians were located and reviewed.

CONCLUSIONS

Treatment providers have a history of involvement with segments of the performing arts. The occupational health approach to workplace health issues can effectively complement these efforts. Sources of further information on performing arts health concerns are available.

The effect of unilateral thalamic deep brain stimulation on the vocal dysfunction in a patient with spasmodic dysphonia: interrogating cerebellar and pallidal neural circuits

Spasmodic dysphonia (SD) is a neurological disorder of the voice where a patient's ability to speak is compromised due to involuntary contractions of the intrinsic laryngeal muscles. Since the 1980s, SD has been treated with botulinum toxin A (BTX) injections into the throat. This therapy is limited by the delayed-onset of benefits, wearing-off effects, and repeated injections required every 3 months. In a patient with essential tremor (ET) and coincident SD, the authors set out to quantify the effects of thalamic deep brain stimulation (DBS) on vocal function while investigating the underlying motor thalamic circuitry. A 79-year-old right-handed woman with ET and coincident adductor SD was referred to our neurosurgical team. While primarily treating her limb tremor, the authors studied the effects of unilateral, thalamic DBS on vocal function using the Unified Spasmodic Dysphonia Rating Scale (USDRS) and voice-related quality of life (VRQOL). Since dystonia is increasingly being considered a multinodal network disorder, an anterior trajectory into the left thalamus was deliberately chosen such that the proximal contacts of the electrode were in the ventral oralis anterior (Voa) nucleus (pallidal outflow) and the distal contacts were in the ventral intermediate (Vim) nucleus (cerebellar outflow). In addition to assessing on/off unilateral thalamic Vim stimulation on voice, the authors experimentally assessed low-voltage unilateral Vim, Voa, or multitarget stimulation in a prospective, randomized, doubled-blinded manner. The evaluators were experienced at rating SD and were familiar with the vocal tremor of ET. A Wilcoxon signed-rank test was used to study the pre- and posttreatment effect of DBS on voice. Unilateral left thalamic Vim stimulation (DBS on) significantly improved SD vocal dysfunction compared with no stimulation (DBS off), as measured by the USDRS (p < 0.01) and VRQOL (p < 0.01). In the experimental interrogation, both low-voltage Vim (p < 0.01) and multitarget Vim + Voa (p < 0.01) stimulation were significantly superior to low-voltage Voa stimulation. For the first time, the effects of high-frequency stimulation of different neural circuits in SD have been quantified. Unexpectedly, focused Voa (pallidal outflow) stimulation was inferior to Vim (cerebellar outflow) stimulation despite the classification of SD as a dystonia. While only a single case, scattered reports exist on the positive effects of thalamic DBS on dysphonia. A Phase 1 pilot trial (DEBUSSY; clinical trial no. NCT02558634, clinicaltrials.gov) is underway at the authors' center to evaluate the safety and preliminary efficacy of DBS in SD. The authors hope that this current report stimulates neurosurgeons to investigate this new indication for DBS.

Improvement of Table Tennis Dystonia by Stereotactic Ventro-Oral Thalamotomy: A Case Report

BACKGROUND

Task-specific focal dystonia, such as writer's cramp and musician's cramp, is a type of dystonia that affects performance of particular tasks. Such movement disorders have been treated with stereotactic ventro-oral (Vo) thalamotomy with excellent outcomes. However, there has been no previous report of treatment of sport-related or athlete's dystonia by means of stereotactic surgery. We treated a patient with table tennis-related dystonia with Vo thalamotomy, and evaluated the outcome.

CASE DESCRIPTION

A 20-year-old, female, left-handed table tennis player complained of difficulty hitting a ping-pong ball. She started playing table tennis at 8 years of age, practiced for more than 4 hours every day, and participated in national tournaments. Abnormal flexion of the left wrist when hitting a ball became apparent when she was 19 years old. The abnormal movement emerged on the forehand stroke and, subsequently, on the backhand, until finally she could not continue playing. The diagnosis was task-specific focal dystonia that did not recover with medication. She visited our hospital and underwent right Vo thalamotomy. The surgery was performed using local anesthesia, with the patient swinging a paddle during stimulation and coagulation of the thalamus. Her symptoms had improved completely the day after surgery, such that she was able to participate in tournaments again.

CONCLUSIONS

We applied Vo thalamotomy for the successful treatment of athlete's dystonia, suggesting that this condition has an underlying mechanism similar to that of other task-specific focal dystonias. This provides new hope to patients with athlete's dystonia refractive to other therapies.