Risk Factors for Playing-related Pain among Piano Teachers by Eri Yoshimura

Risk Factors for Playing-related Pain among Piano Teachers Eri Yoshimura, MM; Anncristine Fjellman-Wiklund, RPT, PhD, Pamela Mia Paul, DMA, Cyriel Aerts, and Kris Chesky, PhD

Previous study on the etiology of musculoskeletal problems among elite pianists, including college piano majors, suggest that playingrelated pain is traceable, in part, to intrinsic factors such as flexibility and hand size. Musculoskeletal problems among other piano groups, particularly teachers, are less understood. The purpose of this study was to investigate piano teachers and the relationships between playing-related pain and several independent variables. In a study conducted as a replication of a previous study of college pianists, results showed that 91% of piano teachers (n = 47) experience pain while playing. Data from this study support previous findings by highlighting hand size and “overall health” as important related variables. Additional findings suggest that playing-related pain among piano teachers may be positively correlated to stretching as part of warm-up and inversely related to amount of playing. Results continue to support the need for interventions that focus on changing the standard piano key size to better fit pianists with small hands. Med Probl Perform Art 2008;23:107–113.

revious studies on the etiology of musculoskeletal problems among elite pianists, including college piano majors, suggest that problems are traceable, in part, to intrinsic factors such as flexibility and hand span.1 Musculoskeletal problems among other piano groups, particularly teachers, are less understood. To date, systematic methods necessary to support such relationships, including anthropometric and flexibility measures, have not been employed to investigate possible physical problems among piano teachers. Piano teachers are an important group because of the extraordinary impact they have on people interested in learning the piano. In 1989, Brandfonbrener reported that 29% of members of the Music Teachers National Association who responded to a survey reported experiencing an injury.2 Another survey administered a year later to members of the New York State Music Teachers Association reported that 52% experienced “physical problems” related to their piano playing.3 Highlighting the dual concern for both self and students, a dissertation conducted at Columbia University reported that

Ms. Yoshimura is a DMA student in piano performance with a related field of study in music and medicine; Dr. Paul is on the piano faculty; Mr. Aerts is a piano technician; and Dr. Chesky is Director of the Texas Center for Music and Medicine (www.unt.edu/tcmm), University of North Texas, Denton, TX. Dr. Fjellman-Wiklund is Senior Lecturer at the Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden, and at the time of this study was a Visiting Scholar at the Texas Center for Music & Medicine, Denton, TX. Address correspondence and reprint requests to: Eri Yoshimura, MM, Texas Center for Music & Medicine, College of Music, University of North Texas, Avenue C, Denton, TX 76203. Tel 940-565-4126; fax 940-565-2002; email pianoeri@hotmail.com.

over 55% of 211 piano teachers and over two thirds of their students had experienced symptoms of an injury from practicing.4 Redmond and Tiernan5 surveyed the knowledge and awareness of prevention-oriented approaches to playing piano among 42 piano teachers who were members of the Washington State Music Teachers Association. Over 75% of participants reported a desire to obtain more information on injury prevention.5 Turon6 questioned performing arts medicine clinicians (n=36) about the teachers’ role in the prevention of health-related problems among their students. Clinicians recommended improvements in health science or music education courses or seminar/workshops. Our previous study employing survey, anthropometric, and performance engineering approaches for assessing various intrinsic factors revealed that 86% of college students majoring in piano experienced playing-related pain.1 Outcomes from statistical modeling identified primary risk factors as 1) flexibility, 2) physical size/strength/speed, 3) age/ exposure, 4) number of musculoskeletal pain sites, and 5) number of non-musculoskeletal problems. The purpose of this study is to use this approach for investigating professional piano teachers.

METHODS Subjects Subjects were recruited during the 2006 annual conference of the Music Teachers National Association (MTNA) in Austin, Texas, through a poster that was displayed near the main conference meeting rooms. According to the MTNA, approximately 2000 individuals attended the conference, and an estimated 80% were piano teachers. A convenience sample of 56 individuals agreed to participate in this study. Those reporting 0 hrs/wk of teaching (n = 9) were excluded. The final cohort included 47 piano teachers. Procedure / Research Design All research activities were completed on site in a designated meeting room of the conference venue. Participation took about 1 hr for each subject. A questionnaire, anthropometric measurement of upper arm and hand, and bilateral upper-extremity performance tests (range of motion, isometric strength, and rotation speed) were administered after the participants signed of an approved IRB consent form. Digital photograph of hands were taken to assess finger mobility as September 2008 107

TABLE 1. Demographic Characteristics and Music Background Data of Study Participants (n=47) No.

Gender Male Female

8 39

17.0 83.0

Marital status Single Married Widowed

22 23 2

46.8 48.9 4.3

Race Asian Caucasian Hispanic

1 45 1

2.1 95.7 2.1

Age (yrs) No. of children Average amount of sleep (hrs/day) Average amount of exercise (hrs/wk) Average travel (days/mo) Age started piano (yrs) Years of private lessons Years of college instruction in piano Size of hands (subjective)*

Min

Max

Mean

15 0

75 4

42.91 0.89

16.43 1.36

5.0

9.0

7.23

0.87

0.0 0.0 3.0 3.0

15.0 10.0 13.0 30.0

4.59 2.55 6.17 14.53

3.41 2.03 2.00 5.93

0.0 0.60

15.0 10.00

5.81 4.95

3.38 2.56

Cross- and Inter-Correlations and Factor Identification

*Subjects answered on VAS (0–10 cm)

described in our previous report. Playing-related pain was assessed using 10-cm visual analog scales (VAS) in response to the following four questions: • • • •

Do you experience pain when playing? Do you experience pain after playing? Does pain stop you from playing the piano? How much of your playing is affected by your pain?

Data collection procedures and statistical analyses were identical to those used in our previous study of college piano majors.1

RESULTS Descriptive Analysis Table 1 shows the demographic characteristics and music background of the 47-subject cohort. Subjects ranged in age from 15 to 75 yrs (average, 43 yrs) and included 8 males (17%) and 39 females (83%). Over 95% of subjects reported caucasian ethnicity. Their maximum number of children was 4, with 1 child on average. The average amount of physical exercise was 4.6 hrs/wk. Subjects reported an average of 9 hrs/wk of practice time and >16 hrs of teaching per week (Table 2). The average number of hours of hand activities other than piano playing was close to 10 hrs. 108

As shown in Table 3, some subjects answered that they always experience pain during and after playing (indicated as 10.00). Ninety-one percent of subjects answered that they feel pain when playing. Eighteen subjects reported mild problems with headache, and 7 indicated severe problems with stage fright. More than 90% of subjects reported musculoskeletal and non-musculoskeletal problems in one or more locations (Table 4). Table 5 shows that the average left-hand digit-to-digit spans were higher than spans on the right hand. These differences were significant (p < 0.05). Right-side anthropometric characteristics were generally larger compared to the left side, except for hand span and upper arm length. As shown in Table 6, the average range of motion and rotation speed was greater for supination compared to pronation. Left supination represented the weakest isometric strength measure. The mean differences between right and left side were not statistically significant except for isometric strength (p = 0.000).

Medical Problems of Performing Artists

Table 7 shows the variables that are significantly correlated with dependent variables (the four pain questions). Overall, exposure (duration of playing) was inversely correlated with the dependent variables. Warm-up habits were strongly and positively correlated with pain when and after playing. Based on correlations between independent variables listed in Table 7, variables were categorized into four groups (factors) labeled as: 1) exposure, 2) warm-up habits, 3) size/strength, and 4) number of musculoskeletal problems. Size and strength were categorized into one factor because they were significantly correlated, as shown in Table 8. The number of musculoskeletal problems and non-musculoskeletal problems was treated similarly. One specific variable was selected from each factor (Table 8) for each dependent variable (the four pain questions). The selected variables were different for each model because the choice was based on the correlation index associated with each dependent variable (Table 9). The procedures for choosing independent variables were the same as used in the previous study. The second highest correlated variables were specially indicated. The number of musculoskeletal problems was selected over non-musculoskeletal problems for factor 4 because it was more significantly correlated with dependent variables. Regression Analysis As depicted in Table 10, results from the regression analysis showed that model 1 and 2 were statistically significant (p<0.05). The adjusted R2 values showed that model 1 accounted for almost 30% of the variance (adjusted R2 = 0.296) and model 2 accounted for 26% of the variance (adjusted R2 = 0.263) in the criterion variable (“Do you experience pain when playing?” and “Do you experience pain after playing?”).

TABLE 2. Practice Habits

Practice hrs per wk Lesson hrs per wk Accompanying hrs per wk Chamber music/ensemble hrs per wk Teaching hrs per wk Keyboard related activities hrs per wk No. of performances in school per semester No. of performance outside school per semester Practice hrs on upright piano per wk Practice hrs on grand piano per wk Do you warm-up before practice?* Physical warm-up time spent (min) Psychological warm-up time spent (min) Musical warm-up time spent (min) Do you take breaks during practice?* How long are your breaks? (min) How often do you take breaks? (hr) Do you stop practice because of physical fatigue?* Do you stop practice because of mental fatigue?* Primary hand activities time spent (hrs/wk)

Minimum

Maximum

Mean

0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

28.0 2.5 20.0 10.0 40.0 10.0 16.0 50.0 40.0 54.0 10.0 15.0 20.0 35.0 10.0 45.0 5.0 10.0 10.0 35.0

9.08 0.38 2.20 0.83 16.63 1.49 1.66 3.36 2.51 11.66 5.30 2.18 1.42 9.40 6.45 8.86 1.27 4.56 4.91 9.53

7.95 0.64 3.56 1.68 9.63 2.34 3.28 7.90 6.74 12.32 3.46 3.06 3.57 8.20 3.21 7.85 0.88 3.34 2.94 9.16

*Subjects answered on VAS (0â&#x20AC;&#x201C;10 cm)

TABLE 3. Responses to Pain Questions and Non-musculoskeletal Problems Pain Questions

Minimum

Maximum

Mean

0.00 0.00 0.00 0.00

10.00 10.00 10.00 100.00

3.11 2.73 2.70 31.10

2.76 2.70 2.99 32.20

Do you experience pain when playing?* Do you experience pain after playing?* Does pain stop you from playing?* How much of your playing is affected by pain?* (%) None

Mild

Severe

Non-Musculoskeletal Problems

No.

Acquired dental malocclusion Acute anxiety Asthma Blackouts/dizziness Chest discomfort Chin rest sore Depression Earaches Eye strain Fatigue Headache Hearing loss Heart condition Hemorrhoids High blood pressure Inguinal hernia Loss of lip Loss of seal Mouth lesions Respiratory allergies Sleep disturbances Stage fright TMJ syndrome Ulcer Varicose veins Weight problems

40 35 41 40 40 43 34 39 27 27 26 35 42 40 35 44 44 44 44 31 32 21 34 44 39 32

90.9 81.4 93.2 90.9 90.9 97.7 77.3 88.6 61.4 61.4 59.1 79.5 95.5 93.0 79.5 100 100 100 100 70.5 72.7 47.7 77.3 100 88.6 72.7

3 4 3 3 4 0 9 5 17 13 18 8 1 3 9 0 0 0 0 11 12 16 8 0 5 11

6.8 9.3 6.8 6.8 9.1 0 20.5 11.4 38.6 29.5 40.9 18.2 2.3 7.0 20.5 0 0 0 0 25.0 27.3 36.4 18.2 0 11.4 25.0

1 4 0 1 0 1 1 0 0 4 0 1 1 0 0 0 0 0 0 2 0 7 2 0 0 1

2.3 9.3 0 2.3 0 2.3 2.3 0 0 9.1 0 2.3 2.3 0 0 0 0 0 0 4.5 0 15.9 4.5 0 0 2.3

*Subjects answered on VAS (0â&#x20AC;&#x201C;10 cm) September 2008 109

TABLE 4. Number of Musculoskeletal Pain Sites and Non-Musculoskeletal Problems Musculoskeletal Pain Sites ____________________

Non-musculoskeletal Problems ____________________

No.

0 1 2 3 4 5 6 7 8 9 10

4 11 10 7 7 2 1 1 0 1 0

9.1 25.0 22.7 15.9 15.9 4.5 2.3 2.3 0 2.3 0

4 2 9 6 4 4 4 2 6 1 2

9.1 4.5 20.5 13.6 9.1 9.1 9.1 4.5 13.6 2.3 4.5

Total

100.0

DISCUSSION Results from this study indicate that prevalence rates for playing-related pain among piano teachers is high and that certain factors continue to help explain this occupational health concern. Consistent with our previous study of college-level piano majors, the results support the hypotheses that smaller hand size and less strength are correlated with pain. An “overall health” construct, based on the number of

musculoskeletal pain sites and number of non-musculoskeletal problems, also re-emerged as an important factor. New to this study, positive correlations were observed between variables related to warm-up and pain. This finding contradicts the universal teaching principle that encourages pianists to warm up before playing.5,7–9 The variable “physical warm-up” was described as “stretching” by nearly all subjects (95%) who answered that they do physical warm-ups. According to a recent meta-analysis of studies of stretching as a tool to prevent sport injuries, data are insufficient to either endorse or discontinue routine stretching before exercising in order to prevent injury.10 Some argue that static stretching be excluded from warm-ups for strength and power activities.11 Of further concern, several studies have reported significant decreases in muscular strength following stretching, apparently from decreased contractile forces and neuromuscular drive.12–14 Although it is not clear what type of stretching was employed by subjects in this study, pianist (especially with small hands) are known to passively pull fingers with the opposite hand to perform stretches of the wrist flexor muscles statically. Some may do it for more flexibility between digit to digit. This type of stretching has been shown to result in significant decreases in isometric grip strength in young adults.15 If stretching does contribute to piano-related pain, additional research is warranted and should allow for detailed descriptions of the type, extent, time, and reason for stretching in order to better understand the role of stretching prior to piano playing.

TABLE 5. Anthropometric Measures of Upper Extremity

Height (cm) Weight (kg) Left upper arm length (mm) Right upper arm length (mm) Left forearm length (mm) Right forearm length (mm) Left hand length (mm) Right hand length (mm) Left wrist circumference (mm) Right wrist circumference (mm) Left index finger diameter (mm) Right index finger diameter (mm) Left hand volume (mL) Right hand volume (mL) Left hand span (mm) Right hand span (mm) Left max. interval on keyboard Right max. interval on keyboard Body mass index Left thumb–index span (deg) Right thumb–index span (deg) Left 2–3 span (deg) Right 2–3 span (deg) Left 3–4 span (deg) Right 3–4 span (deg) Left 4–5 span (deg) Right 4–5 span (deg) 110

Medical Problems of Performing Artists

Minimum

Maximum

Mean

154.90 46.8 280.0 226.0 204.5 203.0 156.0 156.0 140.0 140.0 16.5 16.8 125.0 187.5 190.0 183.0 8 8 18.34 37 38 10 18 5 11 24 20

182.9 113.6 362.0 362.0 303.0 354.0 213.0 222.0 181.0 182.0 21.6 22.9 700.0 700.0 250.0 256.0 11 10 39.84 103 96 53 53 45 44 58 55

167.69 69.68 309.36 308.27 250.60 253.53 176.55 177.32 157.28 158.46 18.43 18.87 322.19 333.13 213.36 212.02 9.40 9.24 24.74 80.40 74.14 36.21 34.92 28.21 26.29 42.67 39.83

7.47 14.39 18.93 22.36 20.60 28.44 12.67 12.79 10.90 11.39 1.28 1.36 135.56 136.18 13.76 16.16 0.78 0.73 4.79 14.10 13.68 8.37 8.04 7.35 8.03 7.53 8.36

TABLE 6. Basic Elements of Performance Minimum

Maximum

Mean

62.4 85.9 58.3 18.0

155.7 150.7 150.0 167.1

104.82 124.15 104.76 123.52

21.01 17.11 18.56 22.92

175.0 135.0 115.0 164.0

996.0 1307.0 1210.0 1541.0

517.26 604.23 534.53 692.63

206.30 360.01 265.11 363.80

Isometric strength Left pronation (N-m) Left supination (N-m) Right pronation (N-m) Right supination (N-m)

2.6 1.8 1.8 3.1

16.7 10.1 10.7 14.0

6.97 4.40 5.32 7.02

2.75 1.87 2.53 2.23

Pinch strength Left (N) Right (N)

0.6 1.0

2.7 4.8

1.84 2.19

0.56 0.77

Range of motion Left pronation (deg) Left supination (deg) Right pronation (deg) Right supination (deg) Rotation speed Left pronation (deg/sec) Left supination (deg/sec) Right pronation (deg/sec) Right supination (deg/sec)

No.

Hand dominance Right Left

42 3

93.3 6.7

Also new to this study, the inversely correlated relationship between the duration of playing and pain indicates that the people who play less frequently report more pain. This finding suggests a possible threshold level of playing that minimizes problems associated with underuse. In comparison to rates reported in our previous study on elite student pianists,1 piano teachers report a higher prevalence rate for pain. These differences may be attributable to

intrinsic characteristics (age, race, etc.), performance and or practice habits (practice hours, teaching hours, etc.), or some other component of a complex and multidimensional phenomenon; however, hand size continues to emerge as an important factor for pianists. As Maclver16 points out, the size of hands vary considerably from individual to individual, but the size of the standard keyboard does not, and this mismatch requires those with small hands to stretch to a point

TABLE 7. Variables Correlated with One or More Dependent Variables

Variables significantly correlated with dependent variables Average amount of sleep Yrs of college instruction in piano Practice hrs per wk Accompanying hrs per wk Practice hrs on grand piano per wk Warm-up before practice Physical warm-up time spent Stop practice because of physical fatigue Right wrist circumference Left interval on keyboard Right 2–3 span Pinch strength left No. of non-MS problems No. of MS pain sites

Dependent Variables ________________________________________________________________________ Do you Do you Does pain How much of experience pain experience pain stop you from your playing is ewhen playing? after playing? playing the piano? affected by your pain? 0.178 –0.361* –0.223 –0.287 –0.328* 0.227 0.364* 0.347* –0.317* –0.318* 0.142 –0.034 0.320* 0.390*

0.277 –0.208 –0.205 –0.296* –0.220 0.323* 0.464† 0.361* –0.085 –0.181 0.096 0.094 0.359* 0.403†

0.224 –0.108 –0.344* –0.069 –0.178 0.139 0.079 0.327* –0.175 –0.159 0.229 –0.146 0.096 0.191

0.374* –0.086 –0.172 0.085 –0.148 0.098 0.192 0.288 –0.274 –0.281 0.338* –0.339* –0.005 0.354*

*Correlation is significant at the 0.05 level (2-tailed). †Correlation is significant at the 0.01 level (2-tailed). September 2008 111

FIGURE 1. A, Small hand playing a chord (B–C#–G#–B) on the standard keyboard. B, Same hand (hand span 185 mm) playing same chord on an ergonomically modified keyboard.

of discomfort. This is easily observable in the pianist shown in Figure 1A. This photo of a pianist with a small hand span (185 mm) shows that the hand flattens out, pulls back toward the front of the keys, and stretches, particularly at the base of thumb, in order to reach an octave. One approach for helping pianist with small hands is to ergonomically modify the piano.16 Figure 1B shows the same pianist performing the same chord (B–C#–G#–B) on a modified piano with keys that are 1/16 narrower than the standard size key. The hand appears much more natural, comfortable, and less stretched, particularly at the base of the

TABLE 8. Four Factors with Related Variables Factor 1—Exposure

Years of college instruction in piano Practice hours per week Accompanying hour per week Practice hour on grand piano per week

Factor 2—Warm-up habits Warm-up before practice Physical warm-up time spent Factor 3—Size/strength

Right wrist circumference Left interval on keyboard Pinch strength left

Factor 4—No. of MS and non-MS problems

thumb. Anecdotal evidence from elite-level college piano majors who are using this type of intervention at the University of North Texas, including the primary author of this paper, suggests that this approach significantly reduces pain and discomfort while allowing performance of repertoire that would be otherwise difficult and painful.

CONCLUSION The findings of the current study support a multidimensional model of musculoskeletal injury causation. Due to the complexity associated with multiple risk factors contributing to piano-related pain and the limitations associated with the current study, additional research is warranted, including studies with larger samples in order to characterize age- and gender-specific differences. Additional assessments regarding prevalence of pain associated with warm-up and other performance-related tasks, including repertoire practiced, need to be developed and used to determine possible causal relationships between these variables. In order to reduce problems among piano teachers, efforts are needed to infuse research findings into the evolution of practice and pedagogy. Long-term adoption of such practices should follow outcomes-based research that demonstrates reduction of prevalence rates and severity levels for piano-related problems.

TABLE 9. Regression Model Model 1 Do you experience pain when playing?

Model 2 Do you experience pain after playing?

Model 3 Does pain stop you from playing the piano?

Model 4 How much of your playing is affected by your pain?

Factor 1—Exposure

Yrs of college instruction in piano

Accompanying hrs per wk

Practice hrs per wk

Teaching hrs per wk*

Factor 2—Warm-up habits

Physical warm-up time spent

Warm-up before practice

Physical warm-up time spent

Factor 3—Size/strength

Left interval on keyboard

Right wrist circumference

Left interval on keyboard*

Factor 4—No. of MS problems

No. of MS problems

*Second highest correlated variable. 112

Medical Problems of Performing Artists

TABLE 10. Regression Data

Predictors Model 1 Factor 1 Factor 2 Factor 3 Factor 4

Yrs of college instruction in piano Physical warm-up time spent Left interval on keyboard No. of MS problems

–0.232 0.290 –0.200 0.304

Model 2 Factor 1 Factor 2 Factor 3 Factor 4

Accompanying hrs per wk Physical warm-up time spent Left interval on keyboard No. of MS problems

–0.306 0.233 –0.048 0.359

Model 3 Factor 1 Factor 2 Factor 3 Factor 4

Practice hrs per wk Warm-up before practice Right wrist circumference No. of MS problems

–0.331 0.052 –0.071 0.241

Model 4 Factor 1 Factor 2 Factor 3 Factor 4

Teaching hrs per wk Physical warm-up time spent Left interval on keyboard No. of MS problems

–0.236 –0.005 –0.162 0.310

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9. 10. 11. 12. 13.

14. 15. 16.

Adjusted R2

p-Value

0.296

4.472

0.006

0.263

3.937

0.011

0.069

1.667

0.182

0.113

2.052

0.113

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