Quality and usability of clinical assessments of static standing and sitting posture: A systematic review.

BACKGROUND: A validated method to assess sitting and standing posture in a clinical setting is needed to guide diagnosis, treatment and evaluation of these postures. At present, no systematic overview of assessment methods, their clinimetric properties, and usability is available. OBJECTIVE: The objective of this study was to provide such an overview and to interpret the results for clinical practice. METHODS: A systematic literature review was performed according to international guidelines. Two independent reviewers assessed risk of bias, clinimetric values of the assessment methods, and their usability. Quality of evidence and strength of recommendations were determined according to the Grading of Recommendations Assessment, Development and Evaluation working group (GRADE). RESULTS: Out of 27,680 records, 41 eligible studies were included. Thirty-two assessment instruments were identified, clustered into five categories. The methodological quality of 27 (66%) of the articles was moderate to good. Reliability was most frequently studied. Little information was found about validity and none about responsiveness. CONCLUSIONS: Based on a moderate level of evidence, a tentative recommendation can be made to use a direct visual observation method with global posture recorded by a trained observer applying a rating scale.

Risk Factors for Musculoskeletal Complaints in Female Musicians: A Systematic Review and Exploration for Future Studies.

BACKGROUND: Female musicians are prone to the development of musculoskeletal complaints (MSC). The etiology of this increased risk is poorly understood. As the number of professional female musicians increases, so does the importance of understanding female-specific risk factors for MSC in musicians. OBJECTIVE: To provide an overview of current literature of proven and possible risk factors/etiology of MSC in female musicians, and to identify topics for future studies. METHODS: Systematic review performed according to international guidelines. A database search was performed in MEDLINE (PubMed), Embase, CINAHL, Cochrane, PsycINFO, clinicaltrials.gov, and gray literature. Studies were independently selected and rated by two reviewers. QUIPS and STROBE guidelines were used for assessing quality and risk of bias. Risk factors were categorized by means of the theoretical framework of the International Classification of Functioning (ICF) and evaluated using the Bradford Hill criteria for causality. RESULTS: Out of 1,924 records, 10 eligible studies were included. A low to moderate level of methodological quality was present in the studies. Fifteen risk factors could be identified from the included studies, which were positioned in the ICF model. The two most frequently mentioned female-specific risk factors were hand size and joint laxity. None of the risk factors fulfilled Bradford Hill's criteria for causality. Many other risk factors were suggested, while a number of expected causes were not encountered. CONCLUSION: At this moment, no evidence-based deductions can be made about female-specific risk factors for MSC in musicians. There is a lack of high-quality studies in this field and a need for studies with a different focus and a prospective study design.

Towards Consensus on Clinical Assessment of Embouchure in Brass Players: A Delphi Study.

AIMS: The objective of this study was to determine the content validity of an assessment instrument for embouchure (the "CODE of Embouchure") which covers the main aspects of the construct of embouchure in brass players. METHODS: The study design followed the Delphi technique. A select panel of 35 international experts gave their opinion via a three-round digital Delphi survey as to whether the instrument as a whole, and its items, adequately measure the construct of embouchure. Criteria for consensus and whether items should go through to the next Delphi round were pre-determined. Data were independently analyzed by two researchers. The CREDES guidelines were used for conducting and reporting of the study. RESULTS: Consensus was reached over 64% and 73% of the closed questions in the first and third rounds, respectively. A second round was necessary to resolve intra- and inter-expert contradicting information. Finally, 5 items were added to the instrument, 3 items were removed, and 23 items were adjusted. Consensus was reached in 63 items (98%). The final multi-item assessment instrument consists of 4 domains and 64 items. CONCLUSIONS: Content validity of most aspects of the "CODE of embouchure" instrument was established.

Reliability of an instrument for screening hand profiles: The Practical Hand Evaluation.

STUDY DESIGN: Psychometric study with 2-week interval. INTRODUCTION: Musculoskeletal hand complaints are common among manual workers. Mismatch between anthropometric hand features and tasks can affect the ability to perform hand activities, with an increased risk of complaints. Although screening of these features may improve diagnosis and treatment, no validated screening tool is available. The Practical Hand Evaluation (PHE) screening tool might fill this gap, but its psychometric properties are unknown. PURPOSE OF THE STUDY: To test the reliability of the PHE and to explore the feasibility of item reduction of the PHE. METHODS: Right-hand profiles of 117 healthy volunteers (66 women, 51 men; mean age, 22.8 years) were independently assessed 4 times by 6 couples of researchers using the PHE, twice on day 1 and twice 2-3 weeks later. Intrarater and inter-rater reliability (intraclass correlations), standard error of measurement (SEM), potential confounding factors (gender, joint hyperlaxity, and measurement order) affecting the instrument's reliability (limits of agreement), and collinearity between the PHE items were determined (variation inflation factor analysis and hierarchical clustering of correlation coefficients). RESULTS: The intrarater and inter-rater reliabilities of the PHE were good for 12 of 14 items (86%; r = 0.67-0.90). Absolute SEM varied between 2.01 and 9.23 mm. The percentage of shifts of at least 2 classes in a repeated measurement was <15%. Cluster analysis identified 6 clusters of hand items. DISCUSSION: The reliability for nearly all PHE items is good. Measurement errors were substantial relative to variances in the reference population, but not to gender, joint laxity and order of administration. Clustering into 6 seperated clusters of items was possible. CONCLUSIONS: The PHE fulfills many of the criteria for screening of anthropometrics of the hand. Its reliability is high. The SEM might be improved with future adaptations toward a digital photographic PHE. Reduction to 6 items seems also possible.

Variation in occupational exposure associated with musculoskeletal complaints: a cross-sectional study among professional bassists.

BACKGROUND: Variation in occupational exposure is assumed to have a protective effect against the development of musculoskeletal complaints (MSC), but this common assumption is not strongly supported by the literature. Among musicians, who have a high prevalence of MSC, many play more than one type of instrument (multi-instrumentalism) for many hours a day. Since multi-instrumentalism implies greater variation in ergonomic load of specific musculoskeletal areas than mono-instrumentalism, musicians are a suitable study population to test whether the above assumption is true. PURPOSE: To investigate in a sample of professional bass players whether multi-instrumentalists are less likely to have MSC than mono-instrumentalists. METHODS: Participants were 141 professional and professional student double bassists and bass guitarists. Demographic, MSC and exposure characteristics were collected online with self-constructed and existing questionnaires. Logistic regression analysis was used to test the association between multi- versus mono-instrumentalism and MSC, adjusted for confounders. RESULTS: The prevalence of having MSC in the neck, back, right shoulder area and both wrist areas did not differ significantly between the two groups. Further analysis revealed that the likelihood of having MSC in the left shoulder area was higher in multi-instrumentalists compared to mono-instrumentalists (Odds ratio 0.30, 95% CI 0.119-0.753, p = 0.010). CONCLUSION: In this sample of professional bass players, no protective effect of multi-instrumentalism against MSC was found. Multi-instrumentalism was associated with a higher prevalence of MSC in the left shoulder. This result challenges theoretical and clinical assumptions in occupational and pain medicine.

Fundamentals of Embouchure in Brass Players: Towards a Definition and Clinical Assessment.

Brass players may experience problems producing an optimal sound (or range of sounds) in their instrument. Assessing and treating dysfunctional embouchure requires knowledge of functional embouchure, but peer-reviewed literature on dysfunctional and functional embouchure is scarce. OBJECTIVE: This study aimed to provide a narrative overview of embouchure based on information from different scientific and clinical fields. This should be regarded as a first step in constructing a reliable, valid, and practical multi-item method to assess embouchure for brass players. METHODS: Literature reviews were conducted concerning: 1) the definition of embouchure, 2) physics and acoustics of embouchure, 3) functioning of embouchure-related structures, and 4) instruments to assess embouchure. Also, embouchure experts (clinicians, scientists, and elite wind players) were consulted for information and discussion. RESULTS: A proposal for a new definition of embouchure, an overview of the relevant physics and acoustics, functions of embouchure-related body structures, and the main methods to measure embouchure in brass playing are presented. CONCLUSION: Peer-reviewed information about the fundamentals of dysfunctional embouchure is scarce and sometimes contradictory. A new definition for embouchure is proposed: embouchure is the process needed to adjust the amount, pressure, and direction of the air flow (generated by the breath support) as it travels through the mouth cavity and between the lips, by the position and/or movements of the tongue, teeth, jaws, cheeks, and lips, to produce a tone in a wind instrument. An integrative overview is presented which can serve as a transparent foundation for the present understanding of functional and dysfunctional embouchure and for developing an evidence-based multi-item assessment instrument.

Relation between muscle activation pattern and pain: an explorative study in a bassists population.

OBJECTIVE: To explore the muscle activation patterns in relation to pain complaints in bassists studied during a musical task. This study was based on the assumption that pain complaints are caused by increased muscle activation during playing or relaxation and/or faster onset of fatigue of muscles. DESIGN: Cross-sectional study. SETTING: Nonclinical. PARTICIPANTS: Student bass guitarists (N=36) from conservatories in the Netherlands. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Bassists played a standard music piece for 30 minutes. Muscle activation levels and pain were recorded. Pain was registered with a Numeric Rating Scale (NRS 0-10). The muscle activation level of both the trapezius muscles and flexor carpi radialis was measured with sEMG: sEMG as the percentage of the maximal voluntary isometric contraction (%MVC) and the slope of the sEMG (slope of %MVC) were calculated. The %MVC as a function of time and the slope of %MVC were calculated during playing and for rest periods before and after playing. For statistic analysis, the Mann-Whitney U test and a multilevel multiregression analysis were used for comparing the sEMG data of bassists with and without pain. RESULTS: No significant differences in %MVC or the slope of %MVC were between the bassists with and without pain complaints. CONCLUSIONS: The results surprisingly indicate that pain complaints of bassists may not be associated with another muscle activation pattern. It is, therefore, not likely that pain is caused by increased muscle activation during playing and/or relaxation, nor by faster onset of fatigue.