Nationwide survey of hip fractures in Japan.

To elucidate the current status of hip fracture incidence and treatment in Japan, a tally of hip fractures in patients from 1998 to 2000 was conducted in Japanese Orthopaedic Association-related hospitals. Response rates were from 40.5% to 55.6% in each observation year. The survey found a total of 110,747 new hip fractures aged 35 years old and over during the survey years. Age- and gender-specific number of patients increased with age and peaked at the age of 80-84 years, then leveled off after 85 years of age. The number of patients with femoral neck fractures exceeded that with trochanteric fractures before 75 years of age, and these figures became inverted thereafter. More left hips were fractured than right in all survey years; however, the difference was not significant. The most common cause of hip fractures was a simple fall; 68.8% sustained fractures indoors, and there was a significant monthly variation. Ninety-three percent of the patients with femoral neck fractures and 94% of the patients with trochanteric fractures were treated surgically, and about three fourths were treated with hemiarthroplasty among patients with femoral neck fractures. The mean hospitalization period was 56.4 days during the observation period.