Three-dimensional motion analysis of upper limb movement in the bowing armof string-playing musicians

Objectives. To explore the role of three-dimensional movement analysis in d efining patterns of joint movement while bowing on different stringed instr uments, and its potential for future use by the clinician in the study of m usculoskeletal problems in musicians. Design and methods. A protocol was developed for analysis of bowing arm mov ements using the MacReflex 3-D analysis system-including definition of mark er sites, positioning of the musician within the calibrated area and standa rdised bowing sequences. This protocol was then used to determine whether t he system was sensitive to differences between instrument types and to vari ation in bowing style and technique between individual players. The ranges of movement in the shoulder, elbow and wrist were compared between instrume nt groups in a cohort of 39 asymptomatic string players. Results. The system gave reproducible results on repeated testing, and demo nstrated clear differences between instruments, as well as stylistic differ ences between players. Range of shoulder movement increased progressively t owards the upper register of the cello, while decreasing on the violin. Max imum elevation of the shoulder was significantly greater on the cello (P < 0.001), while elbow flexion, and therefore range, was consistently greater on the violin. Conclusions. Clear and reproducible differences in style and technique were demonstrated between individuals. The increased range of shoulder movement in the upper register of the 'cello may contribute to the greater prevalen ce of neck and shoulder symptoms among 'cellists. Further study is required to establish whether different musculoskeletal symptoms produce characteri stic patterns which could help in diagnosis and development is required to make the system feasible for routine use. Relevance Musculoskeletal problems are common among musicians. Different in struments and playing positions make different demands on joints and may co ntribute to the variance in reported incidence of musculoskeletal symptoms among violinists and cellists. Three-dimensional analysis may prove helpful in the future for the diagnosis of different musculoskeletal syndromes in string players, or for identifying movement patterns which could exacerbate repetitive strain injuries. However, as this is the first application of t he technique in this complex area, preliminary work was required to establi sh feasibility and to obtain data on normal players. (C) 1999 Elsevier Scie nce Ltd. All rights reserved.