Is anterior pelvic ring fixation associated with lower incidence of posterior hardware failure in elderly patients with pelvic ring injuries?

PURPOSE: Few studies assess failure risk of pelvic ring constructs in elderly patients. This study aimed to identify patient, injury, and fixation characteristics associated with implant positional change, altered weightbearing restrictions, and revision surgery in operatively managed geriatric pelvic ring injuries. METHODS: This retrospective cohort study at a single academic Level I trauma center included patients aged 65 years or older with operatively treated pelvic ring injuries and a minimum 6 month follow-up. The primary outcome was the incidence of postoperative implant positional change. Secondary outcomes were revision surgery and postoperative weightbearing restriction changes resulting from implant migration. RESULTS: 215 patients were included (mean age 74.0 ± 6.9 years; 57% female). Radiographic implant positional change occurred in 23.7% of patients (6.5% anterior, 17.7% posterior). Weightbearing restrictions were altered in 4.2% due to implant loosening, and revision surgery was performed in 4.2% (0.9% hardware removal, 3.3% revision fixation). On multivariate analysis, posterior implant positional change was independently associated with a protective effect from age > 80 years (odds ratio (OR) 0.2, 95% confidence interval (CI) 0.1-0.8, p = 0.016) and anterior ring fixation (OR 0.2, 95% CI 0.1-0.4, p < 0.001). Among patients with anterior injuries, anterior pelvic ring fixation was likewise protective against revision surgery or adverse changes in weightbearing status (OR 0.3, 95% CI 0.1-0.9, p = 0.045). CONCLUSIONS: In geriatric pelvic ring injuries, anterior pelvic ring stabilization was associated with lower incidence of implant positional change and subsequent revision surgery or weightbearing restriction changes.