Prior Fragility Fractures are Associated With Higher Risk of Bone Health-Related Complications Within 8-Years Following Lumbar Fusion

Abstract

Study Design: Retrospective study Objective: To determine the 8-year risk of revision lumbar fusion, pseudoarthrosis, mechanical failure, fragility fracture, and vertebral compression fracture in patients with a prior fragility fracture compared to those without. Summary of Background Data: Osteoporosis is a known modifiable risk factor for revision following lumbar fusion due to inadequate fixation. Patients with prior fragility fractures have been shown to have increased bone health-related complications following various orthopedic surgeries, however there is a paucity of literature that identifies these complications in patients undergoing lumbar fusion. Methods: Patients aged 50 years and older who underwent elective lumbar fusion were identified in a large national database and stratified based on whether they sustained a fragility fracture within 3 years prior to fusion. These patients were propensity-score matched to a control based on age, gender, and Charlson Comorbidity Index (CCI) using a 1:1 ratio. Kaplan-Meier and Cox Proportional Hazards analyses were used to observe the cumulative incidences and risk of complications within 8-years of index surgery. Results: After matching, 8,805 patients were included in both cohorts. Patients who sustained a prior fragility fracture had a higher risk of revision (Hazard Ratio [HR]: 1.46; 95% Confidence Interval [CI]: 1.26-1.69; P<0.001), pseudoarthrosis (HR: 1.31; 95% CI: 1.17-1.48; P<0.001), mechanical failure (HR: 2.08; 95% CI: 1.78-2.45; P<0.001), secondary fragility fracture (HR: 6.36; 95% CI: 5.86-6.90; P<0.001), and vertebral compression fracture (HR: 7.47; 95% CI: 7.68-8.21; P<0.001) when compared to the control cohort. Conclusion: Patients who sustain a fragility fracture prior to lumbar fusion have an increased risk of revision, pseudoarthrosis, and mechanical failure within 8 years. Surgeons should be aware of this high-risk patient population and consider bone health screening and treatment to reduce these preventable complications.