Several studies have shown that playing-related musculoskeletal disorders (PRMDs) present a significant health problem for musicians. To examine physiological, psychological, and behavioral risk factors of musicians' PRMDs, data for a case-control analysis were collected from classically-trained professional and university student musicians in the Canadian province of Ontario in 1994. Two-hundred and eighty-one subjects completed a self-report questionnaire and hypermobility and hand-span measurements. Cases were identified according to an operational PRMD definition developed by musicians and health care professionals in a qualitative study. Logistic regression was used to compare data from 44 prevalent PRMD cases who had no previous history of a PRMD, and 90 controls who had never experienced a PRMD. Data from all subjects were analyzed to examine the role of a prior PRMD on the risk of a current PRMD. This study suggests that females and string players were at a higher PRMD risk. A number of other individual characteristics were also important determinants of the development of a PRMD. Warming up before and taking breaks during practice sessions protected the subject from a PRMD. Given the high proportion of musicians who experience PRMDs, prevention programs are warranted.