Diagnostic Imaging Strategies for Occult Hip Fractures: A Decision and Cost–Effectiveness Analysis

Abstract

Objective: Hip fractures cause significant morbidity and mortality. Determining the optimal diagnostic strategy for the subset of patients with potential occult hip fracture remains challenging. We determined the most cost-effective strategy for the diagnosis of occult hip fractures from the choices of performing only computed tomography (CT), performing only magnetic resonance imaging (MRI), performing CT and if negative performing MRI (MRI-selective strategy) or discharging the patient without advanced imaging. Methods: We developed a decision-analytic model to compare outcomes and costs of different diagnostic strategies for the diagnosis of an occult hip fracture from a societal perspective. Model inputs were derived from charge data, Medicare reimbursements, and the literature. Strategies with an incremental cost–effectiveness ratio (ICER) below $100,000 per quality-adjusted life-year (QALY) gained were considered cost-effective. We tested the robustness of our results using probabilistic sensitivity analysis. Results: Compared to a CT strategy, MRI provides an additional 0.05 QALY at an incremental cost of $1,227 and ICER of $25,438/QALY. For facilities without MRI capability, if the cost of transfer is below $1,228, transferring the patient to a MRI-capable facility is the most cost-effective strategy. Above this cost, employing a CT and if negative transfer to a MRI-capable facility strategy was more cost-effective. When the cost of a transfer reached more than $4,039, it became more cost-effective to only obtain a CT. Conclusion: MRI is a cost-effective strategy for the diagnosis of an occult hip fracture. For facilities without MRI capability, the most cost-effective strategy depends on the cost of the interfacility transfer.