Prior Fragility Fractures are Associated with a Higher Risk of Bone Health-Related Complications Within Eight Years Following Lumbar Fusion

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 with 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. Patients and 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 three years prior to fusion. These patients were propensity-score matched to a control based on age, gender, and Charlson the comorbidity index using a 1:1 ratio. Kaplan-Meier and Cox proportional hazards analyses were used to observe the cumulative incidences and risk of complications within eight years of index surgery. Results. After matching, 8805 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% 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 with 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 eight years. Surgeons should be aware of this high-risk patient population and consider bone health screening and treatment to reduce these preventable complications.