Summary: Using national discharge and medical claims data, we studied the epidemiology of femoral fractures from 1996 to 2006. The annual hip fracture incidence declined from 600/100,000 to 400/100,000, without decline in the more rare femur fractures. Incidence rates for subtrochanteric and femoral shaft fractures were each below 20 per 100,000.
Introduction: This study's purpose is to describe the site-specific epidemiology of femur fractures among people aged 50 and older.
Methods: Using the National Hospital Discharge Survey from 1996 to 2006 and a large medical claims database (MarketScan), we studied epidemiology of all femur fractures. Hip fractures were grouped together; subtrochanteric, shaft, and distal femur fractures were kept separate.
Results: In females, the overall hospital discharge rates of hip fracture decreased from about 600/100,00 to 400/100,000 person-years from 1996 to 2006. Subtrochanteric, femoral shaft, and lower femur rates remained stable, each approximately 20 per 100,000 person-years. Similar trends but lower rates existed in males. No significant trends were found in any of these fractures during the more recent years of 2002-2006 (MarketScan data). Using MarketScan, the overall incidence of hip fracture was <300/100,000 person-years; incidence of subtrochanteric and femoral shaft fractures combined was <25/100,000 person-years and distal femur fracture incidence was <18/100,000 person-years in females; rates were lower in males. The incidence of hip and other femur fractures increased exponentially with age.
Conclusions: We found no evidence of an increasing incidence of any femoral fracture. Hip fracture incidence is declining but the incidence of each of the more rare femur fractures (distal to the lesser trochanter) is stable over time.