Showing posts with label focal dystonia. Show all posts
Showing posts with label focal dystonia. Show all posts

Tuesday, January 3, 2012

Guided imagery in music training and performance

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I    n order to have fast mobility and clarity on left-hand fingers, string players have to train their fingers to have these 3 elements when dropping their left-hand fingers on the fingerboard: speed; strength; and the fast release right after the drop. The 3 elements on the left-hand fingers take training to build up the strength of the muscles and the speed of the reflex of the fast release. Of course, any ‘tool’ that we gain from our technical training is ultimately to be used to create music that would touch listeners. Sometimes when musicians concentrate too much on technical elements, their music tends to be too mechanical, too careful, and lacks emotion. By contrast, when musicians concentrate on being musical, it actually helps the technical things. For example, whenever I feel my fingers stiffen in fast passages, I always find thinking something light and bubbly helps to increase my fingers’ lightness, mobility, and fast articulations. Whenever I try to sustain a long note [and yet try to musically project vitality and suspense, despite the temporary absence of pitch-change or the lack of overt dynamics changes while the note lasts], I remind myself about the struggles and tension of the music. Whenever I try to create smooth bow changes, I often picture a [calligraphy] paint brush changing its direction, instead of which muscle to move first!”  —  Jackie Lee, Heartland Music Academy, 2012.
Jackie LeeI n reply to the previous post, I received the helpful advice above.

A nother CMT reader emailed me to ask whether there was any scientific research literature that establishes the effectiveness of visual or kinesthetic imagery in music teaching, especially for soloists or chamber performers.

T here’s lots of published research on guided imagery in the neurophysiology and physical medicine and rehab literature—and in the lit for research on aging and stroke. Quite a lot in the dance and sports medicine lit. But there are not very many published controlled research studies in music performance/pedagogy lit, so far as I can tell.

I  will continue looking; please feel free to add comment below or email me if there is a reference that you like.

M eanwhile, here are some links to work that’s relevant to this.
T   he left arm functions, to a large extent, by 'walking' on the fingers. In actual walking, torso balance shifts forward, and it is caught on top of the moving legs. For the cellist's left arm, a similar balance can be felt when the upper arm shifts and must be caught by another finger or the arm will fall over... This ‘walking’ image can be strengthened by imagining that the fingerboard is a staircase... Picturing this helps you feel that your balance is aligned in the Earth's gravity, even though your fingers look angled-back in relation to the surface of the fingerboard.”   —  Jeffrey Solow, cellist, quoted in Bruser, p. 121.
I    n automatic or cyclical movements, actual and motor imagery (MI) durations are similar. When athletes imagine only the dynamic phases of movement or perform MI just before competing, however, the environmental and time constraints lead to underestimating the actual duration [and the benefits of the guided imagery are diminished, despite the speed and ease with which the imagery for brief or cyclical movements is called up]. Conversely, complex attention-demanding movements take longer to image [and so guided imagery for complex movements has impediments to its effectiveness, even if duration over/underestimation does not occur].”   —  Aymeric Guillot, 2005.
T    he bilateral frontal opercular regions [in the brain] are crucial in both preparation for and during music execution and imagining. They may have ‘mirror neuron’ properties that underlie observation or imagining of one’s own performance. The motor areas are differentially activated during the preparation and execution or imagining the sequence.”   —  Rumyana Kristeva, 2003.
Mike Mei, calligrapherD    uring execution of musical sequences in professional musicians, a higher economy of motor areas [in the brain] frees resources for increased connectivity between the finger sequences and auditory as well as somatosensory loops, which may account for the superior musical performance. Professionals also demonstrated more focused activation patterns during imagined musical performance.”   —  Martin Lotze, 2003.

Tuesday, March 8, 2011

NEC First Monday: Buvant à la Source, Laurence Lesser Explains a ‘French’ Program

Laurence Lesser, cellis
T   onight’s program is… ‘French’. Stravinsky? French? Well, yes, at least part of him is.”
  —  Laurence Lesser, cellist, introductory remarks.
T he New England Conservtory ‘First Monday’ program featured, among other things, Belgium-born violist Dimitri Murrath introducing each movement of Couperin’s ‘Le Parnasse’ homage to Arcangelo Corelli by reading aloud the movement’s title and subtext, in impeccable French. Quel réalisme! Quel charme! Vive l’authenticité!
  • Couperin – Le Parnasse, ou L’apothéose de Corelli (James Buswell, John Holland, violins; Laura Blustein, cello; John Gibbons, harpsichord)
  • Stravinsky – Apollo (Masuko Ushioda, Wanzhen Li, violins; Dima Murrath, Sarah Darling, violas; Laurence Lesser, Natasha Brofsky, cellos; Donald Palma, double bass)
  • Ravel – Piano Trio (Hung-Kuan Chen, piano; James Buswell, violin; Laurence Lesser, cello)
L esser gave a 15-min pre-concert talk, explaining various things to us… about his experiencing the then-elderly Stravinsky’s pungent advice to him first-hand, when he was a young cellist just starting out in the mid-1960s; about how Couperin was enthralled with what was shaping music in Italy in the 17th Century and early 18th… the unifying, glorious transnationally-strategic possibilities of it. Parnassus, the home of the Muses, is where the soul of Corelli is conducted—ascension (‘remerciment’) to join the god, Apollo… who is the subject of the second work on the program by Stravinsky. And the piano trio after that… Ravel, who in his own time meditated upon his musical predecessors and the debt owed to them (‘Le Tombeau de Couperin’, etc.).

T he violin cadenza performed by Masuko Ushioda in the Prologue of the Stravinsky was spectacular… indicative of the sonic aggressiveness and beautiful iconoclasm ahead.

I  love that the words ‘analysis’ and ‘performance’ have such wide purviews. The ensemble surely ‘analyzes,’ in preparing and interpreting each work, examining the score and its style including notational idiosyncrasies (e.g., ‘void’ functions, expanded tunings, etc.), music theory, historical practices, and so forth. And ‘performance’ may refer to the live performance, to recordings, to practice, to memorization, to improvisation, and to aesthetic, hermeneutic, social, psychological, cognitive, or motoric/musculoskeletal/neurophysiological aspects of all of these.

U shioda’s cadenza served the rhetorical function of announcing the Apollo character in the story and establishing that figure’s authority. It clarifies which key that character operates in, and transforms the thematic material that has preceded the cadenza. The cadenza provides convincing proof of Ushioda’s violinism prowess. But the supervening ensemble members’ parts reveal that there will be disagreement ahead—Apollo may be a god, but he doesn’t rule the Universe.

T his piece was originally orchestrated by Stravinsky for a 28-piece chamber orchestra. Last night’s performance was arranged for string septet. Both orchestrations have their merits, but I especially liked the septet last night. How clear everything is! How much more intimate, compared to the larger version!

T hought #1: Each of these three pieces is characterized by motives and phrases, repeated and massaged and turned round and round through the whole piece and all the movements and variations... Is this particular delight in variational permutations psychologically an archetypically ‘keyboardist’ thing to do (i.e., composers who are not primarily keyboard artists tend not to do it), or is it in some way idiomatically ‘French’, across these centuries?

T hought #2: Each of these three pieces is ‘cinematic’ in terms of structure and narrative. Is the fondness for the picturesque a distinctively ‘Gallic’ trait, or is this feature more an artifact of what it takes to make a living as a musician/composer in each century, in an exchange-economy, market-driven society?
David Lidov, ‘Is Language a Music?’



Tuesday, February 1, 2011

Musicians’ Focal Dystonia Update 2011

Focal dystonia
L    osses incurred in the wounding and in the healing both serve as ‘seeds’ for growth. We cannot wish away the loss, so it is well if we accept the seeds and nurture them, and see what fruit they bear.”
T here have been several dozen readers (TCP/IP addresses in U.S., Canada, U.K., Greece, Italy, Germany) who have landed on this blog in the past 2 weeks by searching Google with “focal dystonia” and related phrases. Some of them used the phrase ‘personalized medicine’ or ‘genomics testing’ as part of their Google search. In response, I want to provide some new resources, beyond ones in my previous focal dystonia-related posts in past years (links below). It is not my intent that all of the resources will be relevant to everybody who reads this post, only that some of the materials will be useful to some of the readers.

W hile I do not have dystonia myself, I know a couple of musicians who do have it. They developed it after years of intensive performance and work at leading conservatories, after achieving mastery of their respective instruments and after having embarked on promising concert careers. For each of these friends, the condition was career-changing. Both are now teaching, primarily; the shift in their attention is source of much joy and satisfaction, surely, and a fantastic treasure in terms of effective, practical pedagogy imparted to the next generation. But it comes at tremendous cost, in terms of foregone income and beauty—performances and recordings prevented, in careers hobbled by focal dystonia.

M y interest in keeping track of current state-of-the-art with regard to diagnosing and treating focal dystonia is in direct proportion to the distress and disappointment I have witnessed in these friends. Besides the recent spate of anonymous searches and CMT page-views, the emails I receive from CMT readers confirm that this condition frequently goes unrecognized or un-diagnosed for years, depending on whether there are dystonia-experienced clinicians accessible to you, ones who specialize in caring for musicians or other performing artists. In other words, if a doctor has never ever seen a case of dystonia before, the probability that he/she will diagnose one now is disproportionately low. This problem is compounded by the fact that focal dystonia does not have obvious signs and symptoms when seen in the clinic.

W ith the intensifying interest in relatively inexpensive direct-to-consumer (DTC) genomic testing from deCODE and 23andme and other companies and with recent years’ trend toward consumers’ taking progressively greater responsibility for diagnosing and managing their own health conditions, I gather together links below, links to the most recent research literature that bears on genetics and genomic polymorphisms that might enable musicians to look at their DTC genomics tests’ raw file download results and bring that evidence with them when they meet with their physicians. Given that the spectrum of focal dystonia is quite broad and pleomorphic, maybe this will help musicians to take charge of the situation, especially if the doctors seem too inclined to ‘wait and see’ or discount the severity of what the patient in front of them is complaining of. Even if the physician has no prior experience with genomics tests per se, it is hard for the physician to be dismissive when the patient in front of him/her is knowledgeable and comes bearing specific evidence with the expectation the evidence will be discussed.

I n this regard, if one of my friends who has focal dystonia discovered that he does have one of the dystonia-associated genomic polymorphisms, then that discovery might be helpful to him and his wife with regard to preventing dystonia in their kids, insofar as the intensity and duration of musical-instrument practice are strongly correlated with triggering the onset of dystonia. One can be a genetic carrier of the genetic variation but remain asymptomatic so long as one doesn’t hit the trigger-point in terms of over-use or over-training. If you are a parent, such information would surely modulate how you approach the musical education of your children...

A t present, researchers have recognized multiple forms of dystonia that have strong association with genetic variations. They have so far identified multiple genes and chromosomal locations responsible for various forms of dystonia. Most of these are rarer and more severe forms than the focal variety that is seen in musicians. But the same genes—and some of the same variations/mutations—have been found to be involved in cases of musicians’ dystonia.
  • DYT1 (TOR1A) – Early onset-primary dystonia
  • DYT2 () – Autosomal recessive primary dystonia
  • DYT3 (TAF1) – X-linked dystonia
  • DYT4 () – Non-DYT1 spasmodic ‘whispering dysphonia’ [singing]
  • DYT5 (GCH1) – Dopa-responsive dystonia
  • DYT6 (THAP1) – Adolescent-onset mixed-type dystonia
  • DYT7 () – Adult-onset primary dystonia
  • DYT8 (MR1) – Paroxysmal non-kinesigenic dyskinesia
  • DYT9 () – Paroxysmal choreoathetosis with dystonic spasticity
  • DYT10 () – Paroxysmal kinesigenic dyskinesia
  • DYT11 (SGCE) – Myoclonus dystonia
  • DYT12 (ATP1A3) – Rapid-onset dystonia-Parkinsonism (RDP)
  • DYT13 () – Early- and late-onset focal dystonia
  • DYT15 () - Alcohol-responsive myoclonic dystonia
  • DYT16 (PRKRA) - Dystonia-Parkinsonism
  • DYT17 () - Segmental or generalized dystonia with dysphonia [singing]
  • DYT18 (SLC2A1)
  • DYT19 () - Episodic kinesigenic dyskinesia 2
  • DYT20 () - Paroxysmal non-kinesigenic dyskinesia 2
T o the reader who recently emailed me, the Phe205Ile (613T>A; see Calakos 2010, link below) polymorphism in the TOR1A gene on Chr. 9 is associated with jaw/embouchure dystonia in the cases that have been studied to-date, although there may be other genes and polymorphisms associated with that condition/phenotype, too. Unfortunately, this particular SNP polymorphism is not included at this time in the microarray chips that 23andme and deCODEme use for their DTC genomics testing, and it is not available in other presently-available tests either so far as I can tell. There are, however, 7 TOR1A SNPs and 4 TOR1B SNPs that are tested, 16 SNPs in the GCH1 gene, 9 SNPs in SGCE, 2 SNPs in ATP1A3, 6 in MR1, 2 in PRKRA, 2 in TAF1, and so on. These are there in your 23andme raw file download results, ready for you to look at and see whether you do or don’t have a variant polymorphism at one or more of these SNP locations.

A t any rate, there seems to be a pent-up demand for resources, links, referrals, anything at all—an unmet need for new information or updates, year-to-year—plus a considerable amount of new information that has accumulated since I last put up a blog post on this topic. Which is why I gather these things and put them up online right now.

M usicians’ dystonia is a task-specific movement disorder that produces cramping and loss of voluntary motor control of muscles that are involved in highly-trained movements associated with performing music. About 1% of all professional musicians develop musicians’ dystonia, although the percentage may be considerably higher since there are many whose condition is never definitively diagnosed and many whose change of career never comes to the attention of researchers who write the journal articles reporting the nominal 1% prevalence figure.

T he pathophysiology of the disorder is not completely clarified. Findings in neurophysiology testing include reduced inhibitory signals at different levels in the brain, abnormal neuroplasticity, and altered sensory perception. Epidemiologically, there is higher risk for those musicians who play instruments requiring maximal fine-motor skills, such as piano, but the condition also occurs in brass players, double-reed players, and singers. For instruments where workload differs across hands, focal dystonia appears more often in the more intensely-used hand—the right hand in guitarists and lutenists. Preliminary findings also suggest a genetic contribution to focal task-specific dystonia with phenotypic variations including musicians’ dystonia. Treatment options include pharmacological interventions, such as trihexyphenidyl or botulinum toxin-A, as well as retraining programs and ergonomic changes in the instrument. Only a minority of musicians, however, return to fully-normal motor control using the currently available therapies. The non-optimality of current therapies—combined with the expectation that identifying the genes, genetic variations, and receptors that are involved in the condition may lead to new, more-effective therapies targeting those receptors in the nervous system—are what drives the recent genomics-based research in this area.

A t the Glasgow Royal Infirmary’s Department of Physiotherapy, eight musicians recently volunteered to take part in a retraining protocol and were studied by Patrice Berque and collaborators. Intensive ‘constraint-induced therapy’ and motor control retraining at slow speed were the interventions Berque examined. They made video recordings of the subjects playing. They measured ‘Frequency of Abnormal Movements’ scale (FAM), the change in metronome speed achieved during motor control retraining, plus two other dystonia evaluation scales. Over a 12-month period, the FAM scale scores showed statistically and clinically significant decrease in the number of abnormal movements per second of instrumental playing. Statistically, significant changes did not appear until about 8 months of therapy. Berque’s results suggest that a combination of constraint-induced therapy and specific motor control retraining may be a successful strategy for the treatment of musicians’ focal dystonia, and suggest that many months may elapse before significant progress occurs.

I n Cheng’s series, three people were found to have the delGAG deletion in the TOR1A (DYT1) gene, and two patients were found to have polymorphisms in the THAP1 gene (224A>T, 449A>C). The overall mutation frequency was 4.5% in Cheng’s patients, with TOR1A mutations found in 2.7% and THAP1 mutations found in 1.8%. No mutations were detected in the control population of normal Chinese. The significance with respect to musicians’ dystonia is not addressed by Cheng, but, by implication, we may anticipate that the genomic epidemiology of musicians’ dystonia may be subject to racial/ethnic variations in much the same manner as the genomic epidemiology of other forms of dystonia varies by race and ethnic ancestry.







Saturday, May 22, 2010

Lumbricals, Some Getting Stronger, Others Discouragingly Staying the Same

 Lumbrical muscles
G   reat strength is necessary in the fingers, yes, but it comes with playing, if one plays rightly—that is, musically. From the moment one senses that the finger must ‘sing’, it becomes stronger. That is quite a different matter from playing exercises or etudes merely for the sake of strengthening, and saying ‘I must exercise my fingers and make them strong.’ Such playing as this latter sort does not help at all.”
  —  Vladimir Horowitz.
M y guitarist-pianist friend and colleague at work comes and visits with me this week, says that for more than a month he’s been doing exercises to strengthen the lumbrical muscles in his hands. The left hand has been responding, but the right hand—especially the ring finger and pinky—has been staying the same or, paradoxically, might even be getting weaker.

H e worries about focal dystonia. (Jason Solomon of Georgia Guitar Quartet has an excellent article about that here.) He worries about carpal tunnel syndrome (CTS). I am not a neurologist, but I know enough to know when to go and hire one. I ask my friend about whether he has any numbness or difference in sensation among the fingers on the right hand, or between the right and left...

T he fact that my friend is a professional software developer/engineer who spends 70+ hours at a laptop keyboard each week is something the neurologist will need to know, as part of the evaluation—in addition to the heavy hours on guitar and piano. In other words, if what my friend is experiencing is some type of repetitive stress injury (RSI), then characterizing the various types and intensities of repetitive motions will be clinically important.

T he state-of-the-art of hand biomechanics and hand problems of musicians have been a recurring interest for me for some years, so, in response my friend’s immediate situation, I go online and scan the current medical journal literature, to see what, if anything, is new in the last year or two. For his benefit and maybe for your own, I gather some relevant things together in the list of links below.

W here exactly is the ‘carpal tunnel’? The carpal tunnel is the narrow space anatomically between the small carpal bones of the wrist and the ligament called the flexor retinaculum. Here’s how you can find it: Put your left index finger in the center of your right palm, then move the finger about two inches down your palm toward your arm, stopping when your finger approaches the edge of the fleshy part of your hand. Your finger now lies directly over the carpal tunnel. The carpal tunnel is the U-shaped depression with carpal bones below and on either side. The flexor retinaculum ligament stretches over the top of the ‘U’ to make a tunnel-like space. The cross-section of the tunnel is only a centimeter or so, and nine flexor tendons (two to each finger and one to the thumb) have to pass through that little tunnel. The space is so narrow that some of the tendons are bundled on top of each other instead of going side-by-side the way they do outside the tunnel.

B esides tendons, the median nerve also goes through the carpal tunnel. By contrast, the ulnar nerve does not run in the carpal tunnel. The median nerve supplies most of the palm, the thumb, the index finger, the middle finger, and part of the ring finger. The first and second lumbricals (i.e. the two that are most ‘lateral’ on the radial side; index and middle fingers) are innervated by the median nerve. The third and fourth lumbricals (i.e. the most medial two; middle, ring, and little fingers) are innervated by the deep branch of the ulnar nerve. So if what’s going on is actually CTS, then you might expect weakness predominantly in lumbricals and/or interosseous muscles serving the thumb or index finger or middle finger or maybe the middle fingerward side of the ring finger. And you might think ‘ulnar neuropathy’ if the ring finger and/or pinky are predominantly affected.

B ut, gee, knowledge of the neuroanatomy of peripheral nerves in your arm and wrist and hand only gets you part of the way toward figuring out what is going on. In part, this is because of the interconnections elsewhere, including the motor cortex in your brain. Besides clinical evaluation, electrodiagnostic (EDX) tests are usually needed to confirm the diagnosis.

T he lumbrical and interosseous muscles are important in several motions—including flexing and plucking, increasing and diminishing the ‘spread’ of the fingers, and extending/raising the fingers. The lumbricals are used during an ‘upstroke’ when you are writing with a pen or pencil. These are the muscles that make the fingers separate and spread out or, alternately, converge and come together. The lumbrical muscles, with the help of the interosseous muscles, simultaneously flex the metacarpophalangeal (MCP) joints while extending both interphalangeal (IP) joints. In bats and other animals, these muscles are the ones that enable them to spread the wings and grab the air at one instant and flex and draw them in a few tens of milliseconds later and let the air go. If a bat acquired a repetitive stress injury of its lumbricals, on both sides or one side different from the other, it wouldn’t have long to live. Same thing for a seal: you can’t swim and catch fish if your lumbricals are faltering. Serious musicians—people whose livelihood or soul depends on playing—worry about this, as intently as a seal or bat.

T he EDX testing for these conditions is steadily getting more sensitive and more precise. For example, Sheehan and coworkers (link below) studied people referred with suspected carpal tunnel syndrome (CTS) by measuring the ‘second lumbrical-interosseous distal motor latency difference’ (2LI-DML) as well as by other, more standard tests like ‘median-ulnar palmar velocity difference’. The referred cases included 74% who turned out to be CTS. Sheehan suggests that 2LI-DML, which is a more sensitive test than other nerve conduction velocity tests for detecting mild abnormalities, is useful as a screening test for latent CTS on the asymptomatic side.

M otor distal latency (MDL) differences between the median-thenar and ulnar-hypothenar (M-U) muscles and between the median-second lumbrical and ulnar-interossei muscles (2L-INT) have also recently been used to diagnose early or ‘mixed’ cases. After all, there is no law of Nature that says a person can’t have CTS and UNE or CTS and focal dystonia at the same time. In people in whom the conventional nerve conduction tests are so far ‘normal’ despite the symptoms they are having, the neurologist can measure both motor and sensory W-P conduction and in a large percentage of cases this can establish a diagnosis.

U lnar neuropathy at the elbow (UNE) is the second most common compressive neuropathy of the upper limb. Compared to ‘ulnar neuropathy at the elbow’ (UNE), ulnar neuropathy at the wrist (UNW) is rarer and more difficult to localize with routine electrodiagnostic (EDX) tests. In terms of expectation-setting, it is reasonable to anticipate that it may take some time (and multiple visits) to establish an accurate diagnosis and decide on the right treatment plan. In general, these are not things that can be sorted out in a single, quick office visit.

T he important thing—if you are having symptoms like the ones my guitarist friend is having—is to get yourself examined by a neurologist who is experienced in problems of performing artists and who has the equipment and training to perform the newer EDX tests that are available. You can search for practitioners who are diplomates of the American Board of Electrodiagnostic Medicine here. I regret that I don’t know what comparable search resources there may be for consultants having EDX professional certifications in other countries.





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.




Sunday, April 29, 2007

Lutes and Lumbricals

Lumbrical Muscles
DSM: A lute player friend of mine has been having progressively more difficulty with his left hand. Focal Dystonia, probably. Nothing so bad as Leon Fleisher’s difficulties years ago or anything like that. But still a major impediment to his performance practice and concertizing.

CMT: There’s still the problem of diagnostic accuracy for Focal Dystonia—and the imprecision of knowing how a loss of “representational specificity” or other changes in the brain can come about through over-use of the hand; the uncertainty of explaining why Botox injected peripherally actually brings about an improvement in this condition if the cause is ‘central’, in the brain. Is your friend sure that it’s Focal Dystonia and not Carpal Tunnel Syndrome or something else?

DSM: Well, no. The neurologists he’s seen have been inconclusive. One hand surgeon wanted to persuade him to be operated for Carpal Tunnel, but my friend regards that as a last resort. And the neurologists’ EMG and imaging and other studies have not been terribly helpful in ruling anything in or out yet. His main complaint has to do with a loss of strength in the lumbrical muscles in his hand, especially the ones involved in moving the middle finger and the ring finger. So it’s not a textbook picture of Focal Dystonia. I suspect he’ll have to go to one of the Performing Arts Medicine clinics that have neurologists experienced in this, as opposed to the well-meaning neurologists and electromyographers he’s seen so far, who have no particular expertise in the problems of musicians.

CMT: There are probably some string players with variant anatomy who just happen to have asymmetrically strong mechanical connections between the ring and middle extrinsic flexor muscles.

Supposedly the phenomenon of middle-ring ‘enslaving’ or ‘subordination’ has a big neural component. If it’s ‘central’ or ‘neural’ then in principle it should be susceptible to retraining through exercises. The connections between adjacent digits involving tendons and muscle fiber groupings of the deep flexor (flexor digitorum profundus) play a big part, though. The ‘peripheral’ biomechanical component shouldn’t be underestimated—it definitely contributes to some of the ‘enslaving’ or ‘subordination’ of one finger to the other. But recent work is showing that enslaving effects among different hand muscles involve both central neural interaction among the structures controlling flexor muscles and lumbricals in the hand as well as peripheral mechanical interactions.

It’s possible that your friend is someone who just happens to have anatomy with substantial tendon sharing. In medical school, I dissected a hand with two lumbrical muscles at each place where you’d ordinarily find only one, and the muscles inserted to adjacent digits. This anatomical variation is not at all uncommon. And if you’re born with this anatomical variation and choose to play lute, then the motions involved in virtuosic lute playing may place particularly great stresses on your aberrant anatomy, in ways that might not affect persons with conventional anatomy quite so severely.

DSM: So what’s going on when we retrain or ‘retune’ the biomechanics with Constraint-Induced Therapy or other physical therapy techniques?

CMT: Well, we learn independent ring and middle finger motion by altering how we activate the controlling networks in the brain, in the primary motor cortex. Neurons in motor cortex aren’t like house-wiring: they don’t make simple direct connections to individual muscles. Instead, our evolution as mammals has set us up to flex and extend our fingers together and to grasp things. Independent digit movements outside of the index finger and thumb require complex inter-neuron coordination to get the desired balance in muscle force at each joint.

Completely independent digit motion is the result of a complex pattern of activation that isolates a movement by preventing other movements mechanically and perhaps by inhibiting some muscles as well. This is why it takes lots of repetitions to learn such skills. Learning new motor skills changes the way muscles and movements are represented topographically among the cells of the motor cortex, and also the way sensory information is represented in the sensory cortex.

Here’s some anatomy, just to give you an idea of where things are, and why the geometry and biomechanics of the hand are so vulnerable as they are.

Crossection of hand, 4 fingers, distal to thumb










Upper Left

Lower Left

Lower Right

Upper Right


1. Distal palmar fat pad

2. First lumbrical m.

3. Tendons mm. flexors digitorum superficialis and profundus

4. Tendons mm. interosseous
and lumbrical


5. Proximal phalanx, second digit

6. Second lumbrical m.



7. Tendon extensor digitorum communis

8. Dorsal and palmar interosseous mm.

9. Tendon m. extensor indicis proprius

10. Collateral ligament

11. Tendons mm. interosseous
and lumbrical


12. Proximal phalanx, third digit

13. Tendon m. extensor digitorum communis



14. Tendons and mm. dorsal
and palmar interosseous

15. Tendons mm. interosseous
and lumbrical


16. Tendon m. extensor digitorum communis

17. Proximal phalanx, fourth digit

18. Tendons mm. interosseous
and lumbrical


19. Tendons mm. flexors digitorum
superficialis and profundus



20. Proximal phalanx, fifth digit

21. Articular capsule and collateral ligament

22. Interphalangeal joint

23. Middle phalanx, fifth digit

24. Fifth digit, distal segment fat pad

25. Fibrous digital sheath

26. Tendon m. flexor digitorum
profundus



The photomacrograph of a transverse whole-section of the hand passes through the four fingers. The slice is taken of a cadaver hand, a frozen section, distal to the thumb—right at the end of the hand, before the fingers start. You can see that the little finger is separated from the others, which makes sense if you look at your own hand. The gap between the little finger and the ring finger comes proximally further into the hand, compared to the gaps between the other fingers. The articulation (22) between the proximal (20) and middle (23) phalanges is seen in the cross-sectional slice in the picture above. This is a pretty bulky hand. Probably not the hand of a musician. But the image helps to give you and idea of the anatomical relationships just the same.

Notice how the extensor tendon to the ring (fourth) finger is very closely applied to its dorsal surface. Not much clearance there! The tendons and distal ends of both interosseous and lumbrical muscles (8, 11, 14, 15, 18) are identified in the picture in relation to the middle digit proximal phalanx (12). The first (2) and second (6) lumbricals are seen close to, and on the radial side of, their tendons of origin. The two lateral (first and second) lumbricals arise from the radial side of the palmer aspect of the first and second tendons of flexor digitorum profundus. The two medial (third and fourth) arise from adjacent sides of the second and third, and the third and fourth tendons of flexor digitorum profundus. The muscles insert into the radial border of the tendon of extensor digitorum on the back of the proximal phalanx. The compactness of this anatomy reveals why the mechanical leverage and pulley-and-lever structures are so exquisitely sensitive. The fulcrums for the action of the lumbricals on the phalanges operate at a relatively high mechanical advantage (force ratio), and therefore small disturbances in the muscles themselves or in the tendon bundle and the tendons’ insertion points can give rise to surprisingly large disturbances in the motion—velocity of attack and release, power, etc.—at the phalanx.

Principles of Neuroplasticity—Strategies for Rehabilitation for Focal Dystonia through Forced Use:
  • Based on the assumption that patients will more readily use the extremity that is normal (unaffected) unless you restrict it.
  • Forcing the use of the affected extremity will modify muscle structure and increase function.
  • Effective for pianists but not for guitarists or lutenists.

Constraint-Induced Therapy (Sensory Motor Retuning):
  • Elbert, Sterr, and colleagues studied 7 musicians with Focal Dystonia.
  • Forced use on the instrument with a splint that restricted the movement of each finger; 10 days, 7 hrs each day.
  • Six of 7 improved; less improvement for guitarists or lutenists than for pianists.

In the absence of a definitive diagnosis, the Physical Therapist or Rehabilitation Medicine practitioner may treat on an empirical basis:
  • Treat the initial injury as part of [an empirically conjectured—] inflammatory, healing process.
  • Decrease stress and stop negative abnormal patterns of movement.

At least in me, there are strong linkages between the middle and ring fingers when I attempt to flex the middle finger at the distal (end) joints. This probably involves mechanical linkages between the profundus muscles for those two fingers—linkages at the level of both proximal tendon and muscle. Nobody knows whether those linkages can evolve over time under conditions of high repetition stress or over-use.

DSM: Obviously, if inflammation is present, you’d expect that some fibrosis and linkage would occur as part of the healing and response to the inflammation.

CMT: But if no overt tendonitis or other inflammatory process is going on, it’s not clear whether a fibrotic proliferative reaction would occur, to give rise to the kind of symptoms your friend is experiencing. Assuming it’s not Focal Dystonia, the Constraint-Induced Therapy of “retuning” exercises can help to compensate for any abnormal anatomical linkages that might be in his hand. Best of luck to your lutenist friend!