Diagnostic Workup of Ulnar Neuropathy at the Elbow: A Cost-effectiveness Study

Rationale and Objectives

Multiple modalities exist for diagnosing ulnar neuropathy at the elbow (UNE), including electrodiagnostic testing (EDX), ultrasound (US), and magnetic resonance imaging (MRI), with no consensus on the optimal strategy. This study’s objective was to determine the most cost-effective diagnostic strategy in patients with suspected UNE.

Materials and Methods

We developed a decision analytic model from the U.S. healthcare perspective over a 1-year time horizon. Our hypothetical population comprised 56-year-old males with medial elbow pain and/or paresthesias radiating to the hand, without weakness. We compared incremental cost-effectiveness and total net monetary benefit (NMB) of single-modality strategies (EDX, US, MRI) and multimodality strategies (combinations of US/MRI, EDX/US, EDX/MRI). Input probabilities and utility values were obtained from the literature, and costs from Centers for Medicaid & Medicare Services and institutional data. The primary outcome was quality-adjusted life years (QALYs). Willingness-to-pay threshold was $100,000.

Results

The diagnostic strategy utilizing US first, followed by MRI, was favored with the highest total QALYs, .935, and total NMB, $92,667. EDX and US single-modality strategies were less favorable, with lower total QALYs, .894 and .906, respectively, and lower total NMB, $88,866 and $90,022. Other diagnostic strategies were excluded by absolute or extended dominance. One-way sensitivity analyses found model results sensitive to the utility of UNE recovery, but otherwise robust over a range of costs/probabilities.

Conclusion

Our cost-effectiveness analysis suggests an initial US, then MRI is the most cost-effective strategy in the workup of patients with suspected UNE.