Trends in Isolated Pelvic Fracture and 30-Day Survival during a Recent 15-Year Period: A Nationwide Study of the Japan Trauma Data Bank

Background: The epidemiology and treatment of isolated pelvic fracture in Japan are not well under-stood. This study evaluated epidemiological trends in isolated pelvic trauma and in-hospital survival rates during a recent 15-year period.Methods: This retrospective cohort study analyzed data from the Japan Trauma Data Bank for 2004-2018. Patients of any age with isolated pelvic fracture were grouped according to time period, as fol-lows: 2004-2008 (Phase 1), 2009-2013 (Phase 2), and 2014-2018 (Phase 3). The main outcome was 30-day in-hospital survival rate. The data were analyzed using the chi-square, Kruskal-Wallis, and Mantel-Haenszel trend tests. We analyzed change in the main outcome over time in multiple logistic regression analysis fitted with a generalized estimating equation, accounting for within-cluster association.Results: In total, 5,348 isolated pelvic fractures were identified during the study period. There was no significant between-phase difference in proportions of patients who underwent resuscitative balloon oc-clusion of the aorta or external fixation. The proportion of patients who underwent transcatheter arte-rial embolization significantly increased with time (p=0.003), as did the survival rate (Phase 1, 77%; Phase 2, 86%; and Phase 3, 91%; p<0.001). The 30-day in-hospital mortality rate was significantly lower in Phase 3 than in Phase 1 and Phase 2, even after adjustment for hospital clustering and other con-founders (p<0.01).Conclusions: The 30-day in-hospital survival rate after isolated pelvic fracture improved over a 15-year period in Japan. (J Nippon Med Sch 2022; 89: 309?315)