SummaryPelvic-acetabular fractures lead to high mortality in elders and their association between different groups is not known. Our results indicate that older age with pelvic-acetabular fracture was significantly associated with mortality. This finding may help planning and allocating healthcare resources, risk stratification, and optimizing the treatment of pelvic fractures.PurposePelvic or acetabular fractures are among main outcomes of low-energy trauma such as falls, especially in older adults. They represent approximately 3–8% of all fractures and are associated with a high mortality rate ranging from 4 to 28%. This study is aimed at comparing the incidence and trends of hip fractures and pelvic-acetabular fractures in the Taiwanese general population, gender differences in adults aged over 65 years, and mortality risk between pelvic or acetabular fractures and hip fractures and surgery trends in patients with these fractures.MethodsA retrospective study was conducted extracting data from the National Health Insurance Research Database of patients diagnosed with hip fracture and pelvic acetabular fracture between 2000 and 2018.ResultsOlder age with pelvic-acetabular fracture was significantly associated with increased mortality. No significant differences were found in comorbidities between the two fracture groups. Results provide clear epidemiological evidence for trends in pelvic-acetabular fractures in Taiwan and demonstrate the need for better strategies to manage these fractures and comorbidities, particularly in older adults.ConclusionFindings of this study may aid in planning and allocating healthcare resources, risk stratification, and optimizing the treatment of pelvic fractures among older adults in Taiwan.