Mortality and comorbidity after non-operatively managed, low-energy pelvic fracture in patients over age 70: a comparison with an age-matched femoral neck fracture cohort and general population

Background: Research on mortality and comorbidity associated with pelvic fractures in older patients is scarce. We aimed to determine the short- and long-term mortality rates of older patients with a pelvic ring fracture compared with both an age-matched cohort of patients with a femoral neck fracture and a general population, and to investigate 30- and 60-day readmission rates after pelvic fracture. Methods: This was a retrospective cohort study done in an emergency department of a level II/III trauma center. All patients aged over 70 years diagnosed with a pelvic or acetabular fracture between January 2010 and December 2016 in our ED were identified. Two reference populations were used: patients operated due to femoral neck fracture in our institution between 2007 and 2008 and a general population aged 70 years or more. Results: Two hundred nineteen patients were identified. 30- and 90-day mortality was 7.3 and 11.4%, respectively. Compared to the general population, a pelvic fracture was associated with an 8.5-fold (95% CI: 5.2-13.9) and 11.0-fold (95% CI: 5.4-22.3) 90-day mortality risk in females and males, respectively. We could not observe a difference in the risk of 90-day mortality between femoral neck fracture patients and patients with a pelvic fracture. Within 30 days, 28 (12.8%) pelvic fracture patients were readmitted for in-patient care in our hospital. Conclusions: The mortality of older patients with pelvic ring fractures resembles that after hip fracture. Although older patients with a pelvic ring fracture rarely require operative treatment, the severity of the injury should not be considered as a class apart from hip fracture.