Clinical and Epidemiological Correlates of Task-Specific Dystonia in a Large Cohort of Brazilian Music Players

Personality in speed skaters with skater's cramp: A preliminary cross-sectional study

OBJECTIVE

Skater's cramp is a debilitating disorder in expert speedskaters and recent evidence from muscle and movement studies nominate it is a task-specific dystonia (TSD). Building on these studies we investigated clinical features and personality in skater's cramp, hypothesizing that similar to other TSDs, trait emotionality would be higher in affected skaters.

METHODS

In a cross-sectional study we employed the HEXACO inventory to examine the personality of a cohort of skaters with skater's cramp (n = 26) compared to age, sex, and experience-matched controls (n = 28). Affected skaters were selected based on relevant clinical features important to the diagnosis of TSD.

RESULTS

Sentimentality (a sub-factor of emotionality) was higher in affected skaters, but only in the male population. Extraversion was lower in skaters with skater's cramp. Clinical findings resembled other forms of TSD.

DISCUSSION

Higher sentimentality is in line with previous studies in TSD. Lower Extraversion in affected skaters was an unexpected finding that may be a new feature of skater's cramp and TSD. Due to our small sample size and cross-sectional design, these findings are preliminary, but offer tentative evidence of personality differences in skater's cramp in line with TSD.

Muscular and kinematic features in speed skaters indicate a task-specific dystonia

OBJECTIVE

Skater's cramp is a movement disorder in speed skaters. We investigated whether affected skaters matched the disease profile of task-specific dystonia, specifically whether there was evidence of maladaptive muscle activity occurring simultaneously with aberrant movements (jerking). We further examined different skating intensities, positing no change would be more indicative of task-specific dystonia.

METHODS

We analyzed video, kinematic and muscle activity in 14 affected skaters. We measured the angular velocity and electromyographic activity of normalized speed skating strokes using one dimensional statistical non-parametric mapping. Skaters were matched with comparably skilled controls, and filled out a bespoke clinical questionnaire.

RESULTS

Skaters' impacted leg showed over-activation in the peroneus longus, tibialis anterior and gastrocnemius that coincided with higher foot movement compared to their healthy leg and controls. This pattern persisted regardless of skating intensity. Clinical features indicated it was task-specific and painless with common trigger factors including stress, equipment change, and falling.

CONCLUSIONS

We showed aberrant muscular and kinematic activity in a movement disorder in speed skaters indicative of task-specific dystonia.

SIGNIFICANCE

Understanding skater's cramp as a task-specific dystonia could reduce the damage that misdiagnosis and unsuccessful invasive operations have caused. Our quantitative method has value in testing future treatment efficacy.

Occupational Injuries in Musicians: A Literature Review

INTRODUCTION

The U.S. Department of Defense employs more musicians than any other organization in the USA with over 6,000 musicians employed. Musculoskeletal pathologies, behavioral health disorders, hearing loss, and dystonias account for the majority of reasons a musician seek medical care. The aim of this study is to review recent medical literature documenting occupational hazards in musicians.

MATERIALS AND METHODS

Authors performed a literature review of publications related to musician performance-related musculoskeletal disorders (PRMDs) and performance-related pain (PRP), behavioral health disorders, dystonias, and hearing loss, published from 2004 to 2019 PubMed.

RESULTS

The search returned 174 possible articles which, after review and exclusion, yielded 88 articles.

CONCLUSIONS

Medical literature suggests several risk factors for multiple disease categories. Practice time and history of PRMD/PRP were both associated with development of PRMD/PRP and focal dystonia. A history of behavioral health disorder was associated with development of focal dystonia. Clinicians should counsel their musician patients on strategies to minimize risks, and additional research is needed to identify specific causes of illnesses in musician populations.

Dystonia in Performing Artists: Beyond Focal Hand Dystonia

Overuse of specific muscles in perfecting movements in performing arts makes an artist prone to many medical conditions. Musicians' hand dystonia is focal task-specific dystonia (FTSD) of hand among musicians that has been extensively studied. However, embouchure, lower limbs, and laryngeal muscles can also be affected among musicians. Embouchure dystonia (ED) refers to dystonia of the perioral and facial muscles that occurs in musicians while playing embouchure instruments. It is essential to identify ED since the dystonia might become persistent and non-task-specific if the musician continues to play the instrument. Task-specific dystonia of lower limbs among musicians has been exclusively reported among drummers. The diagnosis rests on electromyogram (EMG) of the involved muscles during the task. Singer's dystonia (SD) refers to task-specific laryngeal dystonia that occurs only while singing. The diagnosis of SD is based on laryngeal EMG and spectrographic analysis. Cortical hyperexcitability, loss of inhibition, and aberrant plasticity are central to the pathogenesis in both ED and musicians' hand dystonia. The pathophysiological studies in SD are limited. This review aims to discuss the lesser known dystonias among performing artists - ED, FTSD of lower limb, and SD.

Oro-Pharyngeal Dysphagia in Parkinson's Disease and Related Movement Disorders

Oro-pharyngeal dysphagia is a common symptom in patients with Parkinson’s disease (PD) and related disorders, even in their early stage of diseases. Dysphagia in these patients has been underdiagnosed, probably due to poor the self-awareness of the conditions and the underuse of validated tools and objective instruments for assessment. The early detection and intervention of dysphagia are closely related to improving the quality of life and decreasing the mortality rate in these patients. The purpose of this paper is to give an overview of the characteristics of dysphagia, including the epidemiology, pathophysiology, and clinical symptomatology, in patients with PD compared with other parkinsonian disorders and movement disorders. The management of dysphagia and future research directions related to these disorders are also discussed.