We have undertaken a five-year prospective study of 126 translated two-part fractures of the proximal humerus and present an analysis of the epidemiology and of the factors which affect outcome in elderly patients. The fracture has a unimodal age distribution and rarely affects adults under the age of 50 years. Analysis showed that patients with two-part translated fractures of the surgical neck tended to be independent and relatively fit, despite the fact that their mean age was 72 years. Outcome was determined by the age of each patient and the degree of translation on the initial anteroposterior radiograph. Surgery did not improve the outcome, regardless of the degree of translation.