Epidemiology of fragility fracture of the pelvic ring: a regional population-based study in Northern Japan.

ABSTRACT

Using a regional population-based dataset in Japan, we identified the epidemiological characteristics of patients with fragility fractures of the pelvic ring. The incidence rate was 35.5-121.2 per 100,000 population/year. Age-specific incidence increased after 75 years. This fracture is associated with worse prognosis in terms of walking function and life expectancy. PURPOSE: Fragility fracture of the pelvic ring (FFP) is common among older patients; however, little information is available on the epidemiology of FFP worldwide. We aimed to identify the epidemiological characteristics of patients with FFP using a regional population-based dataset in Japan. METHODS: This descriptive epidemiologic study analyzed data obtained from clinical information of patients diagnosed with FFP from January 1, 2011 through December 31, 2020 at a regional dominant hospital in Japan. We calculated the crude and age-adjusted annual incidences and the age-specific incidence and described epidemiological date, injury characteristics, walking ability before and after FFP, and mortality. Additionally, we investigated factors associated with walking ability. RESULTS: We identified 66 FFP patients, of whom 55 (83.3%) were female, with a mean age of 82.2 years. The crude annual incidence of FFP ranged from 35.5-121.2 per 100,000 population/year during the study period. The age-specific incidence of FFP increased after 75 and 80 years in females and males, respectively. In total, 44.4% of patients had declines in walking ability 1 year after their FFP injuries. Patients with declining walking ability were significantly older (p < 0.01), and age ≥ 80 years was significantly associated with the decline in walking ability (p < 0.01). The 1- and 5-year mortality rates were 15.4% and 39.9%, respectively. CONCLUSION: The incidence rate of FFP was 35.5-121.2 per 100,000 population/year. Age-specific incidence of FFP increased after 75 years. Our results indicate that FFP is associated with worse prognosis of walking function and life expectancy.