Tuesday, October 7, 2008

Progress in Treating Musicians’ Focal Dystonia: 2008 Update

Pianist with focal dystonia
I   have a young student (teenage) who is having progressively more problems with his left hand, with violin. I have heard of musician’s cramp in older people—Leon Fleisher and all that. But I have never heard of it happening in kids. Does it happen and, if so, how common is it? Is there anything new in terms of available options for treating it? Would switching to a different violin help? Would switching to a viola or cello help?”
  —  Anonymous, email to CMT, Beijing.
Joseph Jankovic, a Professor of Neurology at Baylor College of Medicine (Houston) with whom I am acquainted, has recently collaborated on dystonia research with colleagues in Beijing (link below). Because I do not (yet) read Chinese it is only through personal contacts or through publications that appear in English that I become aware of neurologists in China who are specializing in dystonia diagnosis and management. But it is clear that there are a number of Chinese medical centers where you (your student) might go and receive expert care for this condition.
I don’t have any strong advice on this topic (musicians’ focal dystonia). And I don’t have any first-hand experience in diagnosing/treating/managing the condition. But I will gather together below some up-to-date information about current research, plus some links that you may find helpful in seeking expert assistance. As to the part of your question concerning the epidemiology of focal dystonia and the incidence of dystonia in kids, here is a quote that pertains to the experience in the U.S. (Maybe figures like these prevail in other parts of the world but, to my knowledge, no detailed epidemiologic statistics have so far been published.)

A   s many as 1 in 200 (0.5%) [of professional] musicians may be affected during their career, and at performing arts medical centers 8% to 14% of musicians seeking medical attention are ultimately diagnosed with dystonia. Symptoms usually begin in the fourth decade of life, a period when performers are at the peak of their careers, and once present rarely remit.”
  —  Anna Conti, Seth Pullman, and Steven Frucht, The Neurological Institute, Columbia University Medical Center, New York, October 2008.
Dystonia is a movement disorder that causes the muscles in the body to contract or spasm involuntarily. These muscle ccontractions force the body into twisting, repetitive movements, and abnormal postures.
  • Multiple parts of the body can be affected, or sometimes just one such as hands, arms, neck, face, eyes, or vocal cords;
  • Symptoms are usually chronic and progressive;
  • Varying degrees of disability and pain, from mild to severe, interfering with performing on your instrument;
  • Affected body parts specifically are ones that are intensively utilized in your performing—ones that are the focus of intense attention, cognitive effort, and repetitive rehearsal.
There is still no cure for focal dystonia. There is no single treatment or therapy that is appropriate for every person who has focal dystonia. Treatment may include oral medications or Botox® / Myoblock® injections or behavioral retuning/conditioning exercises or, more recently, repetitive transcranial magnetic stimulation (rTMS). The more that research enables us to understand Torsin genes and other elements involved in the development of the condition, the likelier it is that more effective and specific therapies can be devised to treat dystonia.

Focal dystonia is a condition characterized by a loss in motor control of one or more body parts. A single muscle or group of muscles is involved: for example, muscles in the hand and forearm tense and tighten, with the result of making the hand (or part of it) curl. Musicians who have intensively practiced their instruments over a number of years are a group most affected by this condition; usually the diagnosis is made when the person is in her/his 20s to 40s. The reason is that focal dystonia generally arises with repetitive movement of the affected body part(s) over a significant period of time. The condition was long known as an ‘occupational hand cramp.’ It can easily be misdiagnosed as simple overuse or stress of the hand. Although it may not be obvious at symptomatic presentation, the level at which the problem is caused is not the hand (or other affected part), but the brain. If kids are intensively trained and accumulate a high level of repetitive movement history at a younger age, there is no biological reason why they would not experience dystonic symptoms at age 15 which, in earlier generations, might have been more usual at age 25 or 35.

Focal dystonia is almost certainly the most prevalent and the most disabling professional disorder in musicians. It decreases the technical level of performances. For many musicians, it ends their performing career. The musician is progressively unable to control the movement of the affected body part(s) when performing. Yes, there is meaningful life for musicians after focal dystonia, when dystonia treatments are unsuccessful. There are roles in music teaching/coaching, music theory, composing, conducting, recording and producing. There are roles as agents, presenters, and executives in government arts and NGO agencies. All sorts of things. But the mourning over the loss of what could have been is monumental. These are musicians—of all ages—whose gifts in other areas may be wonderful, but whose gifts as performers have been foreclosed upon by the misfortune of neurophysiology and genetics. The motivation to discover the underlying causes and discover better therapies is powerful!

The Chicago-based Dystonia Medical Research Foundation (DMRF) routinely issues research grants to investigators, as do other foundation and governmental granting agencies. Some are studying repetitive transcranial magnetic stimulation (rTMS) for the treatment of focal dystonia (e.g., Drs. Victor Candia; Teresa Kimberley and others).

Musicians With Dystonia [founded under the auspices of the Dystonia Medical Research Foundation (DMRF) in 2000 by professional French Horn player Glen Estrin and Steven Frucht, a neurologist at Columbia-Presbyterian Medical Center in New York] also works to encourage and sponsor original research concerning causes and treatments for focal dystonia. The group is dedicated to serving the special needs of musicians affected by focal dystonia, particularly hand and embouchure dystonias. As division of DMRF, the Musicians with Dystonia group supports innovative research in all populations of affected musicians, regardless of age.

The Musicians Medical Advisory Committee of the DMRF encourages grant applications from researchers addressing physician education programs (so that new innovations are made broadly available in practice, to the widest possible number of affected musicians), not just basic science or theoretical neuroscience studies.

Victor Candia is a fine example of a musician who is conducting practical applied research on dystonia. Victor was born in 1966 in Chile, and for 10+ years he taught classical guitar at music conservatories in Germany. In 1991, he developed severe focal dystonia of his left hand, which ended his career as a professional guitarist. He then studied Psychology at the University of Konstanz, Germany, from 1992 to 2000, where he designed and conducted research studies in musicians with dystonia. After completing his doctoral degree, in 2004 he joined the faculty at the Collegium Helveticum of the University and ETH Zürich, where he conducts research on neurophysiology of emotions, brain plasticity, and focal dystonia. Candia and his colleagues have studied treating focal dystonia with ‘sensorimotor retuning’ (SMR) and other methods, examining the efficacy of those techniques in performing artists. Remodeling cortical networks through sensory-motor retuning (SMR) have achieved long-term reduction in the symptoms of focal hand dystonia. The SMR treatments must be continued over time for the benefits to be sustained—but this finding is itself a very important practical result of Victor’s work. It is not only a matter of ‘what’ to do, but also a matter of ‘how’ and ‘how long’ to do it.

Recent fMRI magnetoencephalographic studies confirm that SMR modifies the ‘representational cortex’ that the brain has for the fingers and the fingers’ relations to each otehr, whereby the representation of the affected hand is reorganized so that it more closely resembles the organization of the non-affected side. Candia and others also observe differences in abnormal ‘tactile acuity’ between patients who have musicians’ dystonia and those with writers’ cramp. Using two-point finger discrimination, Candia’s group has found that dystonic musicians show a dramatic, quantitatively/statistically significant perceptual asymmetry between their hands, while writers’ cramp patients do not. To further evaluate the occurrence of collateral disturbances in focal dystonia, they assessed the clinical histories of more than 100 affected musicians. Solid results. Not anecdotes and qualitative ‘case reports’. Not soft conjectures. Solid, quantitative, actionable answers!

An important finding from Candia’s recent published studies was that dystonic musicians who play a similar first and second instruments consistently report a continuous worsening of their symptoms. In addition, collateral disturbances appeared with a shorter delay when more than one instrument was played. So for the Beijing teacher whose question was the reason for this CMT post, the answer is that substituting viola or cello would probably not yield lasting relief and may, in fact, make the process more rapid or severe. Taken together, the evidence suggests:
  1. that neurological dysfunction can be substantially reversed by context-specific re-training of the affected part(s) [great news!];
  2. reversal of dysfunction may be a slow process over many weeks or months [our hopes and fears, realistically calibrated!];
  3. specific symptomatic and etiological differences among various forms of focal hand dystonia might result from different behavioral experiences and how and where those experiences are stored represented in the brain [helpful for diagnosticians and teachers!]; and
  4. the spread of dystonic symptoms can in many instances be prevented by avoiding any training exercises that entail movement patterns that are similar to the main affected task, and by establishing ‘quotas’ on practice/rehearsal (limiting the amount of performance task-associated movements per day).
Karin Rosenkranz and colleauges in London at Sobell Dept of Motor Neuroscience and Movement Disorders the Institute of Neurology at UCL are also iconic examples of pragmatic research on dystonia. They have recently been working on sensorimotor retuning treatments for focal dystonia. The sensorimotor organization (SMO) of the motor hand area is abnormal in focal hand dystonia and appears to contribute directly to symptoms. In healthy musicians SMO is changed by training with spatial ‘proprioceptive’ stimulation. They tested whether similar interventions reverse the abnormal SMO in musicians’ dystonia and writers’ cramp, anticipating possibly developing them for improved therapies. In six non-musicians, six professional musicians, six patients with musicians’ dystonia, and six patients with writer’s cramp, SMO was explored by measuring changes in ‘short-interval-intracortical-inhibition’ (SICI) during short periods of mechanical hand muscle vibration before and after two training types:
  • AttVIB, involving attention to 15 minutes vibration of the abductor pollicis brevis muscle (APB); and
  • AttIndex, involving attention to neural stimulation of the index finger.
In normal, non-dystonic non-musicians, they found that baseline SMO is ‘spatially differentiated’ in the brain. That is, they found that SICI is reduced in projections to the vibrated parts, but enhanced in projections to the non-vibrated muscles. AttVIB increased and AttIndex reduced the effect of subsequent APB-vibration on SMO.

In healthy, non-dystonic musicians, the baseline SMO is not differentiated as much. AttVIB restored a more differentiated SMO pattern, while AttIndex diminished the effect of APB vibration. But in focal hand dystonia, they found that SMO is completely spatially de-differentiated. AttVIB tended to restore a more differential SMO in musicians’ dystonia (but not in writer’s cramp), while AttIndex failed to induce any changes in both groups.

W  hether the vibration retuning intervention is effective or not apparently depends on the musician’s prior sensorimotor organization (SMO). In musicians’ focal hand dystonia, it’s possible to retrain an abnormal SMO toward a more spatially differentiated pattern.

Steven Frucht and colleagues at The Neurological Institute of New York at Columbia University Medical Center are another group active in conducting research to identify the neurophysiology and genomics of focal dystonia and to evaluate new practical treatments. Have a look at their website (and links below) to see what’s new in their efforts, and to see whether any of the clinical trials that they are conducting may be relevant to you or to your student.

Neuronetics rTMS clinical trials centers, U.S., 2008
The Dystonia Medical Research Foundation has a number of DVDs and videos that you may find useful. They also have a nice Treatments page that provides information on the approaches that are available right now (both medical and non-medical ones), plus a referral service to help you find a neurologist in your area who is experienced in managing focal dystonia in musicians.

Check out DMRF’s Musicians with Dystonia webpage.

Besides recent advances in sensorimotor retuning and other behavioral interventiosn, repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are promising, novel, noninvasive cortical stimulation methods for treatment of dystonia and other movement disorders. They avoid surgical risks and provide advantages in terms of targeting specific neural circuits modulating action of the affected muscles. Repetitive transcranial magnetic stimulation (rTMS) delivered at 0.5 Hz to 5 Hz repetitions and suprathreshold (e.g., ~2 Tesla) intensity produces a progressive facilitation of motor-evoked potential (MEP) amplitude that outlasts the end of stimulation. This effect is related to a short-term enhancement of cortical excitatory interneurons in the brain.

In patients with upper limb dystonia there’s an characteristic abnormal recovery from MEP facilitation after ‘supra-threshold’ 5 Hz rTMS, which suggests an abnormal pattern of short-term cortical plasticity in the brain. The abnormal recovery pattern is diagnostic (‘pathognomonic’) of focal dystonia—so if there’s any diagnostic uncertainty prior to the procedure, it may be resolved beyond a shadow of any doubt after the procedure. rTMS is an outpatient procedure, and each treatment takes only about 30 minutes. But it’s not a particularly pleasant procedure. Not as invasive as ECT, to be sure; but not without discomfort. Depending on the intensity of the frequency and the coil-type that is used to apply the magnetic field, many patients do experience headaches and other unpleasant sensations during and after rTMS. The most critical clinical concern is the risk of seizures during rTMS. Treatable, surely, but not a trivial adverse event if it materializes for you!

After rTMS treatment, the movement-enhancing effects of rTMS in focal dystonia patients last longer than in normal non-dystonic people. rTMS may only need to be repeated once a week or once every two weeks. Multiple mechanisms likely contribute to the clinical effects of rTMS in movement disorders, including normalization of cortical excitability, rebalancing the brain’s distributed neural network activity, and inducing dopamine release in the brain. It remains unclear how to individually adjust rTMS variables for the most beneficial effects on symptoms of dystonia. Nonetheless, the noninvasive nature of rTMS, the minimal side effects it has for most people, the positive effects it has demonstrated in preliminary clinical studies, and the growing evidence for mechanisms of action all make rTMS attractive for ongoing research investigation and for your consideration in the future, for yourself or for your students.

Neuronetics NeuroStar® rTMS device
There is already considerable published evidence that rTMS is clinically effective, and rTMS is now being used in depression and other neurological conditions. But rTMS is slow in achieving recognition and regulatory approval as an accepted option in the therapeutic armamentarium for use in dystonia. Its beneficial effects are admittedly of short duration (days) and inconstant from one patient to the next and within any particular patient over time. These factors mean that presently in many countries rTMS is not ‘covered’ or reimbursed by insurers or health systems.

In the U.S., rTMS devices are still investigational with regard to dystonia treatment—only available to patients enrolled in clinical trials. Some rTMS devices are approved by the U.S. Food and Drug Administration (FDA) for stimulation of peripheral nerves but can be used off-label by physicians to treat other neurological disorders not approved by FDA. But insurers won't pay for rTMS treatments when they are given off-label. So in the U.S. and in other countries, generally patients who want to try rTMS for their dystonia will have to pay for the treatments out-of-pocket.

The same is also true for use of Botox/Myoblock treatments for dystonia in some countries. Until now, there has been inadequate control of the stimulation site. It is possible that the rTMS stimulation site could/should be varied on an individual basis. It seems logical to propose the use of fMRI functional imaging for such a purpose, but its use should be adapted to each individual patient’s symptoms and affected body part(s). Even after localizing the site by using fMRI or other measurments, the rTMS coil has to be placed accurately by the clinician. Procedural consistency is a major issue in producing decisive, actionable research results and journal publications that will convince payors and regulators. Stimulation protocols are currently defined by several parameters: the frequency of the rTMS stimulation (>5 Hz) or inhibition (<1 Hz), and the intensity and the number of stimuli influencing the amplitude and duration of the effect. Unfortunately, the effect has so far been variable in each patient. Paradoxical (non-beneficial and adverse) reactions have been observed in more than 15% of normal individuals treated with rTMS. In other words, don’t undertake rTMS lightly. It is entirely possible that, for you, it might make you worse than you are right now.

rTMS coil and mannequin
Medications used to treat dystonia are a brute-force, nonspecific ‘systemic’ option. Sledge hammer precision. Not ideal, but not to be ignored, particularly in extreme situations. Meds include:
  • Trihexyphenidyl
  • Benztropine
  • Anticonvulsants
  • Procyclidine
  • Muscle relaxants
  • Levodopa/carbidopa
  • Bromocriptine
Botox® or Myoblock® injected directly into the muscles affected by dystonia weakens the muscle. This may help improve symptoms of dystonia for 3 to 4 months, but the relief is in general not permanent. And the weakening may itself prevent concert-level performance, Leon Fleisher’s good results notwithstanding. The botulinum toxin preparation used in China is mostly CBTX-A® (Lanzhou Biological Products Institute, 888 Yanchanglu, Lanzhou, Gansu Lanzhou, Gansu 730046, China; Phone : ‎+86 931 8340311), which is a little less potent than Botox® (and therefore may need to be repeated more often) but much less expensive (Allergan Inc.)

Trihexyphenidyl and other anti-cholinergics that are sometimes used to treat dystonia may produce chorea or other movement disorders that are more severe than the dystonia. So it is best to be cautious. None of these options is ‘benign’; all of them have significant limitations/risks as well as strengths/benefits. You need to consult a neurologist who is expert in the treatment of dystonia in musicians to make a proper choice. [Besides the links above for the Beijing-based CMT commenter/emailer] the links below may help you to find such a person near your location, who can help you review the options and decide.

Meds that themselves sometimes cause dystonia as a side-effect include the following:
  • Levodopa/carbidopa
  • Bromocriptine
  • Antipsychotic meds
  • Metoclopramide
  • Dilantin
  • Calcium channel blockers
  • Selective serotonin reuptake inhibitors
  • Ergotamines
  • Antihistamines (esp. cetirizine Zyrtec)
Focal dystonia has a prevalence of 29.5 per 100,000 people in the general population as reported by Nutt and coworkers at the Mayo Clinic some years ago, but, then and now, dystonia often goes un-diagnosed or mis-diagnosed. Almost certainly the 1-in-200 remark at the top in the blockquote from Anna Conti, Seth Pullman, and Steven Frucht is the relevant figure with regard to musicians—both professional ones and serious amateurs. Curiously childhood- and adolescent-onset primary dystonia is more common in Jews of Eastern European or Ashkenazi ancestry, compared to the general population. Possibly there are genetic factors that will be found to be important in dystonia in Chinese and other populations. Although most cases of focal dystonia in musicians come to the attention of neurologists when the patients are in their 20s or later, it is more and more common to see the condition diagnosed at earlier ages. Possibly this is a correlate of the trend in many countries toward larger numbers of kids receiving intensive training as elite-level musicians, especially in China. But to-date there are no journal articles or other research publications that report on this.

Thank you very much for the question. I hope this post is useful to you. Please feel free to comment or email me again on this topic, or let other CMT readers know what results you have had with interventions you try.




2 comments:

  1. ALL THANKS TO DR WILLIAMS FOR THE GREAT DEED HE HAVE DONE FOR MY DAUGHTER?
    My daughter suffered from dystonia for more than 7 years which we started experiencing in her when she turned 4 year and 5 months we all thought it will end but got even worse as days went by. We tried all several treatments and therapy prescribed by various doctors we met but to no avail, she lost total concentration and always complain of neck discomfort . She usually tells me she haves jerky head movements . This were steady disorder that disrupted her entire life, even at night she slept less because of this.It was during a casual conversation with a friend that i learned about Dr Williams herbal medicine I was able to contact him on his email address. and give him all the necessary information that he needed,few day later he sent me the herbal portion and his medicine was able to restore her back to normal and she is very okay now without any side effects whatsoever. If you have dystonia , do not hesitate to contact him on drwilliams098675@gmail.com for advice and for his product. I hope this also helps someone out there.

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  2. As a sign of gratitude for how my son was saved from dystonia , i decided to reach out to those still suffering from this.
    My son suffered dystonia and it was really tough and heartbreaking for me because he was my all and the symptoms were terrible, we tried various therapies prescribed by our neurologist but none could cure him. I searched for a cure and i saw a testimony of so many people who was cured from dystonia and so many other with similar body problem, and they left the contact of the doctor who had the herbal cure to dystonia . I never imagined dystonia has a cure not until i contacted him and he assured me my son will be fine. I got the herbal medication he recommended and my son used it and in one months he was fully okay even up till this moment he is so full of life. dystonia has a cure and it is a herbal cure contact the doctor for more info on drwilliams098675@gmail.com on how to get the medication. Thanks for reading my testimony .

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