The metal artifacts obscure or mimic pathologies and thus severely limit the diagnostic value of CT imaging in orthopedic applications. The fundamental root cause is the beam hardening effect due to the polychromatic x-ray beam. Recent patents introduce a dual-energy CT with fast-kVp switching technique that allows synthetic monochromatic energy images to be generated through material decomposition. These monochromatic energy images are not only free of metal artifacts, but also available at a broad energy range for optimal contrast at bone-tissue interface. This article summarizes the principle of this advanced CT technology with emphasis in its capability in suppressing metal implantinduced CT artifacts.