Twenty male patients who were attending an occupational health care center because of prolonged (more than three months) shoulder pain were subjected to extensive rheumatological and laboratory examinations. Ergonomic and anthropometric data were compared with those of matched referents. Inflammatory rheumatic diseases were diagnosed for three patients (rheumatoid arthritis for one and reactive arthritis to urinary infections for two). No definite diagnosis was possible with regard to the other 17 patients. Their ages were significantly higher than the mean age of workers at their respective factories and that of industrial workers in Sweden. The anthropometric measurements for these patients did not differ from those of the matched referents or from other Swedish males of the same age. Shoulder load, estimated as work with hands at or above acromion height, was significantly heavier among the patient group than among the referents. Neither the evaluated physical load of their current work nor previous hard work was found to be a significant factor. A follow-up two years later showed a definite deterioration, the majority being on pension or still on sick leave.