A scientific overview of Musician’s Focal Dystonia
Introduction
The aim of this essay is to provide an overview of the types, the symptoms, the prevalence and the current state of research on Musician’s Focal Dystonia (MFD) and investigate and critique existing treatments of the condition. First, the term ‘dystonia’ and its different types are discussed, followed by the description of possible symptoms and their perceived psychological and physical causes. In the next part of the essay, the available treatments, their general outcome, and side effects are listed and critiqued.
Finally, the state of the art is concluded, and suggestions for future research are offered.
At present, medical understanding of this condition is limited: the pathophysiology is unclear, co-morbidity with other physical and psychological conditions is frequent, and treatment approaches vary widely. Beyond the scientific literature on MFD a great deal of anecdotal evidence and personal stories are available. These will be included as pointers on aspects of the condition and its treatment where scientific evidence is lacking.
Musician’s Focal Dystonia and its symptoms
Musician’s Focal Dystonia (MFD) is a painless neurological disorder affecting motor control in muscles which are responsible for fine movements, and it is characterized by abnormalities in muscle tone and movement. It is also called Musician’s Cramp and is but one type of a much larger group of neurological illnesses, called dystonias.
The word has Greek origins and carries the description of the problem: dys+tonia, in which “dys” means “ill” or “bad”, and “tonia” (originally “tonos”), means tension (Dystonia, n.d., para.1.; Dys-, n.d. para.1.)
There are many different types of dystonias affecting different body parts, such as torso (truncal dystonia), neck (cervical dystonia or spasmodic torticollis), tongue and jaws (oromandibular dystonia) and even eyes (blepharospasm). The condition can be generalised (affecting more than one body part) or focal (restricted to a certain group of muscles). Within the group of the focal dystonias there are two main distinctive categories: the task-specific (occupational) and non-task specific dystonias. In theory, they are clearly separated, but a closer examination will show that in reality the line between them is sometimes blurred.
The main characteristic of the task-specific dystonias is that the symptoms occur only when a certain task is executed. The typical feature of the task is that it is performed repeatedly during a prolonged time period, and it generally requires fine motor control. Different sports activities, such as playing darts, golf or baseball, playing musical instruments, singing or writing by hand fall into this category. Other special cases are described in the literature, such as foot dystonia in flamenco dancing (Garcia-Ruiz, del Val, Losada et al., 2011), table tennis dystonia (Asahi, Taira, Ikeda et at. 2017), hairdresser dystonia (Horisawa, Goto, Nakajima et al. 2016), repetitive exercise dystonia (Cutsfourth-Gregory, Ahlskog, McKeon et al., 2016) and computer mouse-related finger dystonia (Suzuki, Takano, Hasimoto, 2012).
However, considering all the different groups who can develop occupational focal dystonia, musicians are at the highest risk. (Altenmüller & Jabusch, 2010).
Musician’s Focal Dystonia is a relatively new condition, the earliest description dates back to the 1830s. The first known sufferer is Robert Schumann, who has been recently diagnosed based on his letters and diaries (Altenmüller, 2006, pp 251-264.). However, the condition did not receive much attention until pianist Gary Graffman openly talked about it in 1981 in a New York Times article (Dunning, 1981). There are cases among the most famous musicians, such as Glenn Gould (Wilson, 2000), Leon Fleicher (Brubach, 2007) and Alex Klein (von Rhein, 2016), but it is still unclear how many sufferers there might be in the music community. Altenmüller and Jabusch, (2006) estimate 1% of all classical musicians, but the accuracy is questionable since many sufferers might not seek medical help at all, out of shame or fear. In addition to this, the condition is hard to diagnose, and many cases might remain undiscovered or misdiagnosed by medical professionals (Rosset-Llobet, Candia, Fabergas i Molas et al., 2009, Sussman, 2015).
The symptoms
The symptoms are either described as cramps and high levels of tension in certain muscles, or the opposite, extreme weakness. Both result in loss of control and make the playing inefficient, or in serious cases, impossible.
Some researchers (Altenmüller and Jabusch, 2006.; Candia, Wienbruch, Elbert et al. 2003) think that some of the involuntary movements can be categorised as compensating movements, due to the loss of power and/or control in the dystonic muscle.
The condition is generally painless unless it is comorbid with a painful condition, such as nerve entrapment or musculoskeletal issues, or when the sufferer forces the playing, generating muscle tension in the body.
MFD can manifest itself in many different ways, depending on the instrument or voice. It can appear in fingers (Altenmuller & Jabusch, 2006), in embouchure, affecting the tongue, jaw and lips (Frucht, Fahn, Greene et al., 2001; Frucht, 2009), in shoulder and arms (Altenmuller & Jabusch, 2009), feet (Lee & Altenmüller, 2014, Asahi, Taira, Ikeda et al., 2018), or vocal chords (Chitkara, Meyer & Keindar, 2006).
The symptoms manifest themselves only when playing, but they might spread to other similar activities. For example, pianists with finger dystonia might experience their symptoms when typing, embouchure dystonia sufferers can have problems with drinking, eating or speaking. In these cases, the line between task-specific and non-task specific dystonia is blurred. Roughly one-third of patients suffer from additional non-task specific dystonic spasms (Altenmüller and Jabusch, 2006).
Research shows that generally, the instrumentalists with the more demanding workload, such as high strings, piano, guitar, and high brass and woodwind are at highest risk. (Lim at al., 2003., Altenmuller & Jabusch, 2006., Tubiana & Chamagne, 2000, pp 369-378).
In spite of the symptoms being experienced in the muscles, the origin of the problem is in the brain: researchers found maladaptive changes in the somatosensory cortex (Candia, Wienbruch, Elbert et al., 2003, Byl, Hamati, Wilson et al., 1996). There is evidence that the representation of the hand in the brain’s somatosensory cortex is expanded in musicians (Rosenkranz, Butler, Williamon et al. 2009.) due to excessive training. It seems that in MFD sufferers these changes developed even more than in healthy musicians, disrupting fine motor control instead of supporting it. This dysfunctional brain plasticity has been described in Byl and her colleagues’ experiment as well (Byl, Merzenich, & Jenkins, 1996).
Perceived risks factors
Male gender
One risk factor in developing MFD on which all studies agree is male gender, based on the demographic data. Different studies found different percentages in their samples, but the overwhelming majority of male sufferers is clear in every sample: 6:1in Lim and Altenmüller’s study (2003), 5:1 in Altenmüller and Jabusch’s work (2006) and 7:1 in Rosset-Llobet’s review (2005). Interestingly, this gender bias also occurs in writer’s cramp (Lim & Altenmüller, 2003).
Heredity
One of the widely discussed perceived causes of MFD is the heredity factor. Dystonic symptoms running in families had been described since the earliest reports of dystonia (Munts & Koehler, 2010), but only with the discovery of the DYT1 gene could the researchers be sure that there is a genetic predisposition. The gene had been found responsible for the early onset of torsion dystonias (Valante, Warner, Jarman et al., 1998) and there is some evidence that it plays its role in writer’s cramp as well (Gasser, Windgassen, Bereznai, et al., 1998). However, research shows that there are salient pathophysiological differences between MFD and writer’s cramp (Rosenkranz, Williamon, Butler et al. 2005), and also that the DYT1 gene’s presence is infrequent in MFD sufferers (Friedman, Klein, Leung et al., 2000.).
In spite of this, some researchers still claim that heredity can play a role in the development of MFD (Altemüller and Jabusch, 2006), based on positive family history found in 6% of their sample.
Overuse
MFD can only occur when a movement is frequently repeated, and since it is often comorbid with repetitive strain injury, nerve entrapment, musculoskeletal problems, and overuse injuries, the question arises whether overuse could be the root of the problem.
This theory seems to be supported by Byl’s research (Byl, Merzenich, & Jenkins 1996), in which monkeys were trained to execute a quick and repetitive task and after 300 trials per day developed dystonic symptoms. Also, their brains showed similar changes in the sensorimotor cortex as in MFD sufferers.
This lines up with Rosenkranz’s opinion when she raises the possibility that ‘MD is a form of training-induced dystonia’ (Rosenkranz et al., 2005, pp 930).
Repetition is one of the main components of MFD, but since the condition does not always occur after a prolonged time of playing, we must conclude that there must be other elements contributing to the onset of MFD.
Trauma, stress, change in practice or technique
It is often described by both researchers and sufferers (Altenmüller & Jabusch, 2006, Tubiana, 2003), that the first onset of the symptoms followed a period of extreme stress, some sort of trauma, change in the instrumental/singing technique or change in the amount or quality of practice. A similar tendency has been described in sports psychology, concerning the ‘yips’ (Rotheram, Thomas, Bawden et al. 2006).
Psychological triggers
For many decades, all types of dystonias were considered psychogenic, not organic. The earliest written diagnoses overemphasise the role of psychological factors and organic factors were not even considered until the 1980s (Munts & Koehler, 2010). The official viewpoint changed after the discovery of the dystonia (DYT1) gene, but the fact the in most of the cases MFD is only triggered by a certain action (Altenmüller & Jabusch, 2006) lead some researchers to investigate the role of psychological factors.
Tubiana (2003) writes that apart from biomechanical factors, psychological traits play an important role in the development of MFD. Also, the presence of anxiety (Jabusch, Müller & Altenmüller, 2004; Enders, Spector & Altenmüller, 2010), perfectionist tendencies and neurotic personality traits (Jabusch & Altenmüller, 2004) has been found in sufferers. Similar research had been done in the case of ‘yips’ or sport focal dystonia, where next to perfectionism and anxiety, obsessive tendencies, social phobia, heightened levels of self- awareness and competitiveness has been added to the list.
Many of these maladaptive traits have been observed in musicians as well. Tubiana writes: “Regarding psychological factors, it seems that most musicians suffering from FD have totally invested themselves in their profession; these people are intense perfectionists and have great artistic ambition.” (Tubiana, 2003, pp 305.)This aligns with Altenmüller’s findings: in one of the research samples of 144 musicians (Altenmüller and Jabusch, 2006), they found 51% soloists, and the rest also filled very responsible positions in orchestras. It is possible that in these positions the environmental factors create more stress, and lead to a more intense practicing behaviour in musicians who develop dystonia. Decourt (1986, pp 152.) agrees with this when he writes: “This does not deny the emotional behaviour common in artists, and the apprehension they have of the socio-professional consequences may lead to an obsessional state which one must take into account.”
Currently, there is no study investigating these traits and their origins in depth, and how they contribute to the onset of the symptoms. The studies which had been conducted (Jabusch, Müller & Altenmüller, 2004, Jabusch & Altenmüller, 2004) claim that perfectionism and anxiety were present before the condition, but they rely on personal recall. The reliability of self-reported retrospective studies has been questioned before (Shipton, Tappin, Vadiveloo et al., 2009), especially if the participants have to remember feelings and events which happened many years ago. Also, for a professional musician, losing one’s ability to play an instrument is a deeply traumatic event, which can make the accuracy of the recall even less solid. It is possible that the described traits are a secondary psychological reaction to the onset of MFD and not a triggering factor. Therefore, in contrast with the quantitative methodology used in the past, qualitative methods might be more suitable exploring this issue, as it was successfully used in the case of sports dystonia (Rotheram, Thomas, Bawden et al., 2006).
Treatments
The official viewpoint regarding MFD is that it is incurable (Altenmüller & Jabusch, 2006), but some researchers disagree with this statement (Tubiana, 2003). However, recovery rates are indeed low, and very few musicians can return to their careers after being affected by the condition (Altenmüller & Jabusch, 2006). Different approaches developed which can be helpful in recovering from the condition, and several success stories have been reported, but in most cases, they improve the symptoms only to a certain extent. Most of the treatments are targeting finger dystonias, which seem to be the most common (Brannfonbrener, 1995), leaving only a few options for those who are suffering from embouchure, foot, arm, neck or shoulder dystonias.
In this section, a short overview will be provided of each available treatment.
Trihexyphenidyl
There had been many attempts to treat the symptoms of MFD with oral medication, with very little success. Trihexyphenidyl is the most helpful among these medications and is frequently used in treating patients, in spite of the high percentage of unresponsiveness and severe side effects. It only seems helpful in the case of finger dystonia and has no effect on embouchure problems. In Altenmüller’s & Jabusch’s (2006) report, out of 67 patients, improvement was reported by only 23, and 22 of these suffered from side effects, such as dry mouth, tiredness, dizziness, memory impairment, depression, impaired visual accommodation, and tremor. Interestingly, most side effects were reported by those who also benefited from the medication and their MFD symptoms improved. The low percentage of perceived improvement and the high percentage of serious side effects show that the treatment of MFD with Trihexyphenidyl is not a durable solution.
Botulinum Toxin
The most common medical treatment for MFD at the moment, in spite of the contradictory evidence, is botulinum toxin (botox) injections. The practice was adopted from the treatment routine of generalised and other serious dystonias (Jankovic, Schwartz & Donovan, 1990), but by medical specialists it has not been confirmed effective, not even in the case of non-task specific focal dystonia (Balash & Giladi, 2004).
Botox is a toxin which blocks the responsiveness and activity of the injected muscle, stopping the involuntary contractions. Since the root of MFD is not in the muscles themselves but in the brain, the treatment is clearly symptomatic and is not bringing longitudinal results. There is a strong critique on using botulinum toxin in the first place in the case of MFD (Tubiana, 2003) since it does not seem to be a permanent solution.
Other issues concerning the injections that it takes skill to be able to inject them into the dystonic muscles, especially since the primary dystonic movement and the compensatory movement are often hard to distinguish. Most injections are given after the visual observation of the dystonic body part, but in some specialised clinics, EMG guided injection technique is used. The fact that this technique is not widely used, and without it, only 37% of the injections reach the target muscle is alarming(Molloy, Shill, Kaelin–Lang et al., 2002).
Apart from these problems, it does not offer any relief for embouchure dystonia sufferers (Altenmüller & Jabusch, 2006), and there is anecdotal evidence that it is potentially dangerous as well since in some cases it distressed other primary functions, such as swallowing or talking.
Brain surgery
An available, but not frequently used method for treating MFD is brain surgery. This risky operation is more often employed in the case of dystonias which have a serious effect on the quality of living and compromise everyday activities, like generalised dystonias (Kupsch, Benecke, Müller et al., 2006). However, primarily in Japan, it is used to treat focal and task-specific or occupational dystonias as well, like hairdresser’s dystonia (Horisawa, Goto, Nakajima et al. 2016), table tennis dystonia (Asahi, Taira, Ikeda et at. 2017), and writer’s cramp (Fukaya, Katayama, Kano et al., 2007). Neurosurgeons report positive changes in the case of MFD as well (Asahi, Taira, Ikeda et al., 2018, Horisawa, Taira, Goto et al., 2013), however, most of these studies are case studies or using a very small sample size, making these findings non-generalizable. In addition to this, there are several drawbacks: the treatment is expensive, risky and not all suffers can get access to it. Also, it needs to be followed by a long recovery period and retraining of certain skills. As we will see, very similar retraining exercises, without the surgery, were claimed to be helpful in treating MFD, relying on brain plasticity (Tubiana, 2003, Candia et al. 2003), questioning the necessity of an expensive and potentially hazardous thalamotomy.
Ergonomic changes
Since the symptom is associated to a certain feedback to the brain, one of the possible solutions is to change the sensations for the dystonic body part, and as a result, the brain receives a different feedback. One of the most frequently used methods is to play in gloves or placing band-aid on the fingers. In other cases, the changes are made on the instrument and can range from placing differently textured materials on the keys to modifying their shape. Some changes are aimed to take the weight away from the dystonic hand with the help of harnesses. In one study (Altenmüller and Jabusch, 2006), 68% of the patients reported improvement, but it is unclear how long these improvements last.
Splints
There is some research investigating the possibility of using splints on the fingers or hand in order to stop the sufferer using it completely for a period of time (Priori, Pesent, Cappellari et al. 2001). Patients reported improvement, but not complete recovery. The treatment is under-studied, and at this point, there is not enough information to decide whether splints could be an effective treatment for focal dystonia.
Dental splint
In embouchure dystonia, the employment of dental splints can be helpful (Satoh, Narita, & Tomimoto 2011), but the treatment is not widely used. It is more commonly employed in the case of temporomandibular (TMJ) pain and disorders (Pierce, Weyant, Block, et al.,1995) which is a painful condition affecting the joint which connects the jawbone to the skull and can also result in tremors. Since the dental splints improved the tremors in TMJ’s patients, they could be a promising treatment for musician’s embouchure dystonia. However, it is not helpful in every single case: researchers have categorised embouchure dystonia into three distinctive sub-types, depending on the exact location of the symptom, masticatory, facial and lingual types, and dental splint have been found useful only in the masticatory type of ED.
Proprioceptive training
This special training is aiming to restore sensorimotor organizationin the brain by giving the patients proprioceptive input. The training restored the over-expanded sensorimotor organization and resulted in improved task-specific motor control. The improvement positively correlated with the neurological changes in the brain itself. (Rosenkranz et al, 2009.)
This type of training is highly experimental and is not yet known what longitudinal results it will bring. Also, the method was only tested in pianists with very similar types or dystonic movements, so the effect on embouchure and other types of dystonia is also unknown. In spite of this, the treatment shows promise since it is easy to deliver, does not have side effects and relatively quick. More research would be beneficial in this field.
Behavioural therapies, retraining
One of the most promising treatment strategies is retraining and different kinds of behavioural therapies. They seem to be more successful than any medical treatment and there are no side effects (Altenmüller & Jabusch, 2006). Since these strategies are mostly exploratory, developed by medical professionals and retrained individuals, there are salient differences between them. Unfortunately, only a few behavioural programs have been thoroughly described and documented, in other cases, the information is anecdotal and supported only by claims made by the therapists or individuals. This section will summarise the most widely used ideas and retraining programs but will not describe all of them in detail.
Most of the retraining strategies rely on brain plasticity, claiming that if the sensorimotor organization could change in a maladaptive manner, it is possible to reverse the process.
Tubiana and Chamagne have created a retraining program (Tubiana & Chamagne, 2000, Tubiana, 2003) based on their clinical experience of treating 600 cases since 1975. The program first aims to correct possibly triggering postural habits and movements by physiotherapy. In the second phase, with the learned, corrected posture, the patient approaches the instrument slowly, carefully avoiding any activities which provoke the symptom. Another well-documented scientific program (Candia, Wienbruch, Elbert et al. 2003) used splints on the healthy fingers to stop the compensatory movements in order to train the dystonic fingers alone, and in many cases resulted in improvement of the symptoms. These results were based not only on the evaluations of the patients but the examination of the functional organization of the somatosensory cortex which showed salient positive changes. However, it is important to note, that both of these therapies worked with finger dystonia sufferers, and in the case of the splint therapy, it is impossible to adapt it to embouchure or other types of dystonia.
There is anecdotal evidence that both Alexander Technique and Feldenkrais Method are helpful in the retraining process, but since they were not created to target this specific problem, they need to be complemented with some other retraining program. There are individuals who claim to be completely recovered from the condition and offer consultations to sufferers, but for commercial reasons, they are reluctant to reveal specifics of their methods, and their programs are generally not published. Without attempting to be exhaustive, the following list contains some of these therapists and their methods.
Joaquin Farias is a Canadian practitioner, who treats different types of movement disorders – including MFD – with movement therapy. There is no scientific research or description on his actual methods, because according to him “rehabilitation experiences are not reproducible because each person is unique and different, and life doesn’t repeat itself.” (Farias, n.d., para. 4.). There are testaments from former sufferers endorsing his methods (Bitti, 2015).
Another known former sufferer and now practitioner is Joaquin Fabra, who believes that MFD is a behavioural disorder, not a neurological one, and should be treated as such (Fabra, n.d.). Scientific research shows otherwise, and Fabra’s views are questioned by specialists and sufferers likewise. However, many former sufferers claim to be cured with Fabra’s approach, which is based on continued playing without caring about the quality or outcome and allowing the body to “remember” the movement.
Anna Detari suffered from embouchure dystonia, and after she retrained herself, she started coaching others with the condition. Her method is based on a combination of optimised posture, breathing and re-learning certain aspects of the playing. (Detari, n.d.)
Akiko Trush, as a former sufferer of a very serious case of finger and palm dystonia, works with pianist, primarily in Japan. Her approach is based on correcting the biomechanical setup, and slow re-learning. (Trush, n.d.)
Concluding this, behavioural therapies, with a few notable exceptions, are not documented, they need to be evaluated and understood. Most of them work with only finger dystonia, not offering any help to embouchure and other dystonia sufferers, but still, these therapies seem to be the most effective in dealing with this issue. However, they are only helpful if the patient is actively engaged in the process, and willing to go through weeks, sometimes months of seemingly fruitless retraining exercises. In general, the patients who are most flexible to change their playing habits, practicing patterns and repertoire are the ones who are the most successful in the retraining programs (Tubiana, 2003).
Possible preventions
Since the pathophysiology of the condition is unclear, it is hard to develop preventative strategies. Based on the comorbidity of MFD and overuse problems, promoting healthy practice patterns and health promotion, in general, could be a good place to start. Also, since there seems to be a comorbidity with unhealthy perfectionism and obsessive tendencies, teachers should deal with extreme cases from the beginning by creating a calm, less competitive learning environment (Enders, Spector, Altenmüllerat al., 2011). The onset of MFD is often triggered by some technical changes (embouchure, hand position, new, different instrument), all these transitions should be handled with care and patience, allowing the students or musicians enough time to adapt to the new conditions.
Life with Musician’s Focal Dystonia
The retraining or rehabilitation from MFD is a long and mentally and physically exhausting process, and success is not guaranteed. Musicians with MFD are often unable to play during this period, and even if they can, it causes heightened levels of stress and discomfort. The literature looking into MFD sufferers’ mental and physical well-being is scarce, in spite the fact that well-being might play an important role in the retraining itself.
One study (Lee, Eich, Ioannou et al., 2015) did not find a significant difference in the life satisfaction of healthy musicians, MFD sufferers who continued playing with the condition, and MFD sufferers who were forced to change profession. They conclude that musicians usually find their way to cope with the condition and regain their life satisfaction. However, a survey study seems a blunt tool to discover the life experience of a possibly perfectionist and obsessively passionate population after the trauma of losing their livelihood and artistic outlet. One very small-scale study with two participants (Zosso & Schoeb, 2012) attempts to understand this complex issue, using qualitative methods and concludes that learning more about this life-changing experience would improve the quality of care. The area needs a more careful and thorough investigation.
Conclusion
Musician’s Focal Dystonia is a complex issue, and its direct causes remain unknown. In spite of the medical viewpoint that it is incurable, there are several promising treatment strategies available. The literature is mostly focused on finger dystonia, therefore more research is needed in the field of other types of MFD.
It seems that purely medical solutions are not showing satisfying results, but more holistic approaches are promising. The cooperation of health care professionals, researchers, psychologists and professional musicians would help us to understand the triggers and causes of the condition in order to create more efficient retraining programs.
In many studies, MFD is compared to writer’s cramp, in spite of the pathophysiological differences (Rosenkranz et al., 2005) and the different circumstances in which the triggering action is performed. Sports dystonia offers a much better comparison, in terms of environmental and psychological factors, while, moving forward, existing research into sports dystonias could offer insights into MFD.
In addition, general awareness must be raised about the condition among both medical professionals and musicians to avoid misdiagnoses and to be able to deliver help to sufferers as soon as possible.
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