BACKGROUND: Understanding past trends and predicted future incidence of hip fractures is important for the assessment of Medicare sustainability and resource allocation. The purpose of this article was an analysis of most recent data on the incidence of hip fractures to predict the number of hip fractures that will occur in the United States from 2010 to 2050 in individuals 45 and older, by sex, and age distribution. METHOD: Prior hip fracture data were obtained from the National Hospital Discharge Survey during the period 1996-2006. These data were obtained from the US Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Health Statistics. Projected population estimates were obtained from the Population Division, US Census Bureau and Statistics, August 14, 2008. We used the past number and incidence of hip fractures extrapolated to population projections to predict the future number of hip fractures to 2050 using Application Software (SAS 9.2; SAS Institute Inc) regression model analysis. RESULTS: Two trends were identified from past reported rates of hip fractures. Trend 1 assumed a continued very slow decline in the incidence of hip fractures in the future yielding a conservative estimate of 458,000 fractures by 2050. Trend 2 ignored the slight decrease in rate over past years and used a constant rate determined from linear regression providing an estimate as high as 1,037,000 in 2050. The largest number of fractures will occur in females older than 65 years. CONCLUSIONS: Future estimates of the number of hip fracture will likely fall between the 2 trends described within and by 2050 may range from 458,000 to 1,037,000 with the largest number occurring in female older than 65 years.