Prognosis of nonspecific work-related musculoskeletal disorders of the neck and upper extremity.

Reviews of work-related musculoskeletal disorders (WMD) of the neck and upper extremity have typically supplied little information on prognosis. This paper reports on the methods and results of a systematic search for evidence on clinical course and prognosis of nonspecific WMD i.e., those without specific clinical diagnoses. Articles were deemed relevant if they provided primary data on current or former worker cases of WMD followed over time. WMD status had to be based on clinical evaluations. The 13 studies which met these criteria were evaluated using clinical epidemiological criteria for validity of prognostic studies. None of the studies was sufficiently strong across the criteria to provide more than weaker evidence on prognosis. Prognostic factors with promise include duration of symptoms and workplace demands. In order to improve the evidence on prognosis of WMD, we recommend closer attention to the following: clear operational definition of cases; documentation of prognostic factors including duration of symptoms and severity at baseline; incorporation of multiple follow-up assessments; inclusion of a range of outcomes; and analysis using stratified or multivariate methods.