[Femoral neck fractures in Nord-Trøndelag 1988-95. Incidence differences between winter and sommer months]

The incidence of hip fractures among the elderly is high. Previous studies have revealed considerable geographical differences in Norway with the highest incidence of hip fractures in Oslo. Using hospital registers, we found there was an annual incidence of first-time hip fractures of 583 per 100,000 inhabitants 50 years and older in the county of Nord-Trøndelag. This incidence is about the same as in Troms county in Northern Norway. The number of fractures almost doubled in the winter months of December and January compared to June and July. This study was not designed to explain these seasonal differences, but some of the reasons may be explained as follows: during the light, summer months elderly people are at less risk when moving about, both indoors and out, whereas they are at greater risk in the winter when roads and pavements are slippery. Preventive measures in the community may reduce the incidence of hip fractures.