Stereotactic Neurosurgery for Writer's Cramp: Report of Two Cases with an Overview of the Literature

Abstract

Background: Writer's cramp is a specific movement disorder with hand muscle cramps in writing, being classified into focal and action-specific dystonia. Stereotactic surgery, such as thalamotomy and deep brain stimulation (DBS), has been reported for writer's cramp; however, the number of reported cases is still scarce and surgical procedures are also controversial. Objectives: In this study, therefore, we present 2 patients who underwent thalamotomy for writer's cramp and systematically review the literature on stereotactic surgery for writer's cramp. Methods: Case reports and literature review are presented. Results: Both patients underwent ventral oral nucleus (Vo) thalamotomy safely. Their symptoms completely disappeared after surgery and did not recur during follow-up periods. In the literature, a total of 31 cases were surgically treated for writer's cramp. Stereotactic surgery included thalamotomy in 25 cases and DBS in 6. The target included the Vo in 17 cases, the ventral intermediate nucleus (Vim) in 3, and both Vo and Vim in 7. Both procedures markedly improved or resolved the symptoms. Transient neurological deficits were observed in 16.0% of patients after thalamotomy. Conclusions: The Vo may be the most effective target to treat writer's cramp. Both thalamotomy and DBS are feasible and effective, but thalamotomy would be a better option, especially in younger or high-risk patients.

Deep Brain Stimulation for Movement Disorders of Basal Ganglia Origin: Restoring Function or Functionality?

“…Compared with GPi DBS, STN DBS may offer the advantage of more rapid improvement for dystonia and reduced stimulation parameters [257]. While there is a prior history of thalamotomy for generalized dystonia, thalamic DBS has not been utilized for this indication, perhaps because of the success with GPi and STN DBS, although thalamic DBS (targeting Vim, or the thalamic ventralis oralis nucleus) is being explored for focal forms of dystonia, such as writer's cramp [263][264][265].…”

Task-specific dystonia: pathophysiology and management

“…This is particularly true in musicians, as the window between treatment efficacy and weakness that impairs function is particularly narrow. Stereotactic brain surgery and deep brain stimulation (thalamic) have been suggested for writing dystonia after claims of benefit in small non-randomised studies 68 69. These approaches should be considered highly experimental particularly while the pathophysiology is so poorly understood.…”

Stereotactic Thalamotomy for Hairdresser's Dystonia: A Case Series

“…However, these phenomena have not been integrally comprehended in association with the available treatments. Vo-thalamotomy has been reported as a highly effective procedure for writer's cramp and musician's dystonia [7,8,9,10,11,12]. The Vo nucleus is the major termination site for basal ganglia outputs, including those from the globus pallidus internus and the cerebellum.…”

“…However, these treatment methods are not always satisfactory [6]. In cases of focal hand dystonia, thalamic lesioning of targets in the ventral lateral nucleus of the thalamus, including the nucleus ventro-oralis (Vo), which consists of the ventral oral anterior nucleus (Voa) and ventral oral posterior nucleus (Vop), have been reported as highly effective treatments for writer's cramp and musician's dystonia [7,8,9,10,11,12]. Although rare, 2 cases of hairdressers with TSFD have been reported without the disclosure of treatments [13,14].…”