Yips and other movement disorders in golfers

Treatment of task-specific dystonia in sports: A systematic review

Introduction

Task specific dystonia is a movement disorder only affecting a highly practiced skill and is found in a broad set of expert movements including in sports. Despite affecting many sports, there is no comprehensive review of treatment options, which is in contrast to better studied forms of task specific dystonia in musicians and writers. For this reason, studies involving an intervention to treat task specific dystonia in sports were systematically reviewed, with special attention for the quality of outcome measures.

Methods

The PICO systematic search strategy was employed on task-specific dystonia, and all synonyms. Inclusion criteria were peer reviewed published studies pertaining to sports, studies with a measurement and/or intervention in TSD, all in English. We excluded abstracts, expert opinions, narrative review articles, unpublished studies, dissertations and studies exclusively relating to choking. We included case reports, case studies and case-control studies.

Results

In April 2022 Pubmed, Embase, Web of Science, and Psychinfo were searched. Of the 7000 articles identified, 31 were included that described psychological and invasive and/or pharmacological interventions. There was a lack of formal standardized outcome measures in studies resulting in low quality evidence for the effectiveness of treatment options. A descriptive synthesis showed emotional regulation was effective, but was exclusively tried in golfers. Interventions like botulinum toxin or pharmacology had a similar effectiveness compared to studies in musicians dystonia, however there was almost no formal evidence for these treatments.

Conclusion

The quality of studies was low with a lack of standardized outcome measures. Future studies with larger cohorts and quantitative outcome measures are needed to improve understanding of treatments for task specific dystonia in athletes.

Anxiety Disorders in Athletes

Athletes and non-athletes experience many anxiety-related symptoms and disorders at comparable rates. Contributory factors may include pressure to perform, public scrutiny, sporting career dissatisfaction, injury, and harassment and abuse in sport. Anxiety may negatively impact sport performance. Specific types of anxiety may have unique presentations in athletes. It is important to rule out general medical and substance-related causes of anxiety symptoms. Psychotherapy and pharmacology treatment options should be considered, bearing in mind athletes' environmental circumstances and physiologies.

It's in the game: A review of neurological lesions associated with sports

INTRODUCTION

The practice of sports may lead to neurological injuries. While relatively uncommon (overall incidence of approximately 2.5%), and mostly benign and transient, some conditions may be life-threatening and permanent. Thus, both clinical neurologists and sports physicians should be aware of their existence and relevance. We aimed to review all sports-related neurological injuries and illnesses reported in the literature.

METHODS

Following SANRA guidelines, we performed a narrative review and searched PubMed and Scopus databases. Relevant sports were selected based on their recognition as an Olympic sport by the International Olympic Committee. Chronic traumatic encephalopathy (CTE) and other neurodegenerative disorders were not included.

RESULTS

A total of 292 studies were included concerning 33 different sports. The most reported neurological injury was damage to the peripheral nervous system. Traumatic injuries have also been extensively reported, including cerebral haemorrhage and arterial dissections. Non-traumatic life-threatening events are infrequent but may also occur, e.g. posterior reversible encephalopathy syndrome, cerebral venous thrombosis, and arterial dissections. Some conditions were predominantly reported in specific sports, e.g. yips in baseball and golf, raising the possibility of a common pathophysiology. Spinal cord infarction due to fibrocartilaginous embolism was reported in several sports associated with minor trauma.

CONCLUSION

Sports-related neurological injuries are increasingly receiving more social and medical attention and are an important cause of morbidity and mortality. This review may serve as a guide to physicians managing these challenging situations.

Sports-Related Dystonia

Background

Task-specific dystonia (TSD) is a form of focal dystonia that occurs in the context of the performance of selective, highly skilled, often repetitive, motor activity. TSD may be apparent during certain tasks such as writing, playing musical instruments, or other activities requiring fine motor control, but may also occur during certain sports, and maybe detrimental to professional athletes' careers. Therefore, sports physicians and movement disorder neurologists need to be aware of the presentation and phenomenology of sports-related dystonia (SRD), the topic of this review.

Methods

A broad PubMed search using a wide range of keywords and combinations was done in October 2021 to identify suitable articles for this review.

Results

Most of the publications are on yips in golfers and on runners' dystonia. Other sports in which SRD has been reported are ice skating, tennis, table tennis, pistol shooting, petanque, baseball, and billiards.

Discussion

Yips, which may affect up to half of the golfers and rarely athletes in other sports (e.g., baseball, cricket, basketball, speed skating, gymnastics) seems to be a multi-factorial form of TSD that is particularly troublesome in highly skilled professional golfers. Runners' dystonia, affecting the foot, leg, and hip (in decreasing order), may evolve into more generalized and less specific dystonia. The pathophysiologic mechanisms of SRD are not well understood. Botulinum toxin has been reported to alleviate dystonia in golfers', runners', and other forms of SRD. Future studies should utilize neurophysiologic, imaging, and other techniques to elucidate mechanisms of this underrecognized group of movement disorders.

Second hit hypothesis in dystonia: Dysfunctional cross talk between neuroplasticity and environment?

One of the great mysteries in dystonia pathophysiology is the role of environmental factors in disease onset and development. Progress has been made in defining the genetic components of dystonic syndromes, still the mechanisms behind the discrepant relationship between dystonic genotype and phenotype remain largely unclear. Within this review, the preclinical and clinical evidence for environmental stressors as disease modifiers in dystonia pathogenesis are summarized and critically evaluated. The potential role of extragenetic factors is discussed in monogenic as well as adult-onset isolated dystonia. The available clinical evidence for a "second hit" is analyzed in light of the reduced penetrance of monogenic dystonic syndromes and put into context with evidence from animal and cellular models. The contradictory studies on adult-onset dystonia are discussed in detail and backed up by evidence from animal models. Taken together, there is clear evidence of a gene-environment interaction in dystonia, which should be considered in the continued quest to unravel dystonia pathophysiology.

Difference in Personality Traits and Symptom Intensity According to the Trigger-Based Classification of Throwing Yips in Baseball Players

The triggers of initial onset of yips symptoms can be broadly divided into psychological and non-psychological factors; however, a trigger-based classification of yips has not been established. This study aims to obtain insight into the prevention of yips by clarifying whether there are differences in symptoms and personality traits according to a trigger-based classification of yips in baseball players. A total of 107 college baseball players responded to a questionnaire assessing the presence or absence of yips and its symptoms. They were classified into the psychologically triggered yips group, the non-psychologically triggered yips group, and the non-yips group based on the presence or absence of yips and the triggers of its initial onset. Additionally, we compared whether personality traits examined by the NEO Five-Factor Inventory differed across these three groups. The psychologically triggered yips group had significantly higher agreeableness scores compared with the non-yips group, whereas the non-psychologically triggered yips group had significantly higher neuroticism scores compared with the psychologically triggered yips group. In the non-psychologically triggered yips group, there was a significantly higher frequency of throwing errors than in the psychologically triggered yips group, with a tendency to develop yips symptoms gradually. Since the trigger-based classification of yips is closely related to the strength of the yips symptoms and the players' personality traits, the results of this study contribute to a better understanding of the symptoms of yips and establishment of the prevention of yips. Large prospective studies are necessary to determine the causal relationship between a trigger-based classification of yips and the personality traits and symptoms of athletes with yips.

Association of the Yips and Musculoskeletal Problems in Highly Skilled Golfers: A Large Scale Epidemiological Study in Japan

The yips are a set of conditions associated with intermittent motor disturbances that affect precision movement, especially in sports. Specifically, skilled golfers suffer from the yips, although its clinical characteristics and pathophysiology have not been well-studied. We surveyed skilled golfers to characterize their yips-related symptoms, to explore potential confounding factors associated with the yips. Golfers’ demographic information, golfing-career-related history, musculoskeletal status and manifestations of the yips are surveyed. Among the 1576 questionnaires distributed, 1457 (92%) responses were received, of which 39% of golfers had experienced the yips. The median age and golfing careers were 48 and 28 years, respectively. Golfers who had experienced the yips were older and had longer golfing careers and more frequent musculoskeletal problems than those without experience of the yips. The multivariate logistic regression analysis revealed that a longer golfing career and musculoskeletal problems were independent factors associated with yips experience. More severe musculoskeletal problems were associated with higher odds of experiencing the yips. A positive association between the yips and musculoskeletal problems was also observed. The yips have similar characteristics to task-specific movement disorders, with a detrimental effect caused by excessive repetition of a routine task. These findings support the notion that the yips are a type of task-specific dystonia.

Modulation of sensorimotor cortical oscillations in athletes with yips

The yips, an involuntary movement impediment that affects performance in skilled athletes, is commonly described as a form of task-specific focal dystonia or as a disorder lying on a continuum with focal dystonia at one end (neurological) and chocking under pressure at the other (psychological). However, its etiology has been remained to be elucidated. In order to understand sensorimotor cortical activity associated with this movement disorder, we examined electroencephalographic oscillations over the bilateral sensorimotor areas during a precision force task in athletes with yips, and compared them with age-, sex-, and years of experience-matched controls. Alpha-band event-related desynchronization (ERD), that occurs during movement execution, was greater in athlete with yips as compared to controls when increasing force output to match a target but not when adjusting the force at around the target. Event-related synchronization that occurs after movement termination was also greater in athletes with yips. There was no significant difference in task performance between groups. The enhanced ERD is suggested to be attributed to dysfunction of inhibitory system or increased allocation of attention to the body part used during the task. Our findings indicate that sensorimotor cortical oscillatory response is increased during movement initiation in athletes with yips.

Clinical and Demographic Characteristics of Upper Limb Dystonia

BACKGROUND

Knowledge of characteristics in upper limb dystonia remains limited, derived primarily from small, single-site studies.

OBJECTIVE

The objective of this study was to characterize demographic and clinical characteristics of upper limb dystonia from the Dystonia Coalition data set, a large, international, multicenter resource.

METHODS

We evaluated clinical and demographic characteristics of 367 participants with upper limb dystonia from onset, comparing across subcategories of focal (with and without dystonia spread) versus nonfocal onset.

RESULTS

Focal onset occurred in 80%; 67% remained focal without spread. Task specificity was most frequent in this subgroup, most often writer's cramp and affecting the dominant limb (83%). Focal onset with spread was more frequent in young onset (<21 years). Focal onset occurred equally in women and men; nonfocal onset affected women disproportionately.

CONCLUSIONS

Upper limb dystonia distribution, focality, and task specificity relate to onset age and likelihood of regional spread. Observations may inform clinical counseling and design, execution, and interpretation of future studies. © 2020 International Parkinson and Movement Disorder Society.

Sex differences in movement disorders

In a range of neurological conditions, including movement disorders, sex-related differences are emerging not only in brain anatomy and function, but also in pathogenesis, clinical features and response to treatment. In Parkinson disease (PD), for example, oestrogens can influence the severity of motor symptoms, whereas elevation of androgens can exacerbate tic disorders. Nevertheless, the real impact of sex differences in movement disorders remains under-recognized. In this article, we provide an up-to-date review of sex-related differences in PD and the most common hyperkinetic movement disorders, namely, essential tremor, dystonia, Huntington disease and other chorea syndromes, and Tourette syndrome and other chronic tic disorders. We highlight the most relevant clinical aspects of movement disorders that differ between men and women. Increased recognition of these differences and their impact on patient care could aid the development of tailored approaches to the management of movement disorders and enable the optimization of preclinical research and clinical studies.

Consensus Statement on the classification of tremors. from the task force on tremor of the International Parkinson and Movement Disorder Society

BACKGROUND

Consensus criteria for classifying tremor disorders were published by the International Parkinson and Movement Disorder Society in 1998. Subsequent advances with regard to essential tremor, tremor associated with dystonia, and other monosymptomatic and indeterminate tremors make a significant revision necessary.

OBJECTIVES

Convene an international panel of experienced investigators to review the definition and classification of tremor.

METHODS

Computerized MEDLINE searches in January 2013 and 2015 were conducted using a combination of text words and MeSH terms: "tremor", "tremor disorders", "essential tremor", "dystonic tremor", and "classification" limited to human studies. Agreement was obtained using consensus development methodology during four in-person meetings, two teleconferences, and numerous manuscript reviews.

RESULTS

Tremor is defined as an involuntary, rhythmic, oscillatory movement of a body part and is classified along two axes: Axis 1-clinical characteristics, including historical features (age at onset, family history, and temporal evolution), tremor characteristics (body distribution, activation condition), associated signs (systemic, neurological), and laboratory tests (electrophysiology, imaging); and Axis 2-etiology (acquired, genetic, or idiopathic). Tremor syndromes, consisting of either isolated tremor or tremor combined with other clinical features, are defined within Axis 1. This classification scheme retains the currently accepted tremor syndromes, including essential tremor, and provides a framework for defining new syndromes.

CONCLUSIONS

This approach should be particularly useful in elucidating isolated tremor syndromes and syndromes consisting of tremor and other signs of uncertain significance. Consistently defined Axis 1 syndromes are needed to facilitate the elucidation of specific etiologies in Axis 2. © 2017 International Parkinson and Movement Disorder Society.

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.

Task-Specific Dystonia in Professional Musicians. A Systematic Review of the Importance of Intensive Playing as a Risk Factor

BACKGROUND

Focal dystonia in professional musicians is a movement disorder that manifests itself during playing. It is a multifactorial condition in which a genetic predisposition and exogenous factors both play a role. Evidence suggests that intensive playing is a risk factor for the development of task-specific dystonia in professional musicians.

METHODS

This review is based on pertinent publications (1950-2013) retrieved by a systematic search in medical and musicological databases. The references of the retrieved publications were also considered in the search.

RESULTS

16 articles with clinical information on a total of 1144 affected musicians were reviewed systematically. Their overall quality was intermediate to poor, and a meta-analysis was therefore not possible. The Bradford Hill criteria were applied to study a possible causative link between intensive playing and musician's dystonia. Musician's dystonia generally arises after at least ten years of intensive playing (corresponding to roughly 10 000 hours of practice). An association was found between the affected limb and the type of instrument: the limb that is subject to the greatest fine motor demands is the one most commonly affected. The average age of onset is 28 to 44 years.

CONCLUSION

The Bradford Hill causality criteria indicate that intensive playing is related to the development of musician's dystonia. In particular, the association of the type of instrument with the site of dystonia supports this thesis. The findings imply that task-specific dystonia in professional musicians should be included in the list of occupational diseases in Germany.

Task-specific dystonia: pathophysiology and management

Task-specific dystonia is a form of isolated focal dystonia with the peculiarity of being displayed only during performance of a specific skilled motor task. This distinctive feature makes task-specific dystonia a particularly mysterious and fascinating neurological condition. In this review, we cover phenomenology and its increasingly broad-spectrum risk factors for the disease, critically review pathophysiological theories and evaluate current therapeutic options. We conclude by highlighting the unique features of task-specific dystonia within the wider concept of dystonia. We emphasise the central contribution of environmental risk factors, and propose a model by which these triggers may impact on the motor control of skilled movement. By viewing task-specific dystonia through this new lens which considers the disorder a modifiable disorder of motor control, we are optimistic that research will yield novel therapeutic avenues for this highly motivated group of patients.

Some unusual sports-related neurologic conditions

PURPOSE OF REVIEW

This article reviews some of the unusual sports-related neurologic disorders within the new and rapidly growing field of sports neurology that neurologists may encounter.

RECENT FINDINGS

Surfer's myelopathy is a potentially tragic disorder predominantly affecting novice surfers, leaving many who are affected by this condition with permanent paralysis. Neck-tongue syndrome is a rare primary headache disorder that can occur in athletes and nonathletes, and consists of paroxysmal neck and occipital pain and transient ipsilateral tongue numbness, triggered by sudden rotation of the neck. Athletes are also at risk for cervical arterial dissections, with golfers especially prone to vertebral rather than carotid dissections. Finally, "the yips" likely represents a form of occupational dystonia described in golfers.

SUMMARY

The syndromes described in this article range from relatively minor syndromes that cause discomfort or abnormal movement to potentially devastating cerebrovascular or myelopathic syndromes. Although the disorders described in this article are not common, they can affect individuals involved in sports at all levels, from the novice to the elite athlete, and may present to any neurologist. Neurologists should be aware of the potential for these syndromes to occur as a consequence of athletic activities in order to provide the most appropriate diagnosis, management, and counseling.

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.