Dr. Hiroshi Takagi’s overview of his navigation study which compared kinematics of ATTUNE and SIGMA. In this small case series, the ATTUNE Knee implants were not associated with paradoxical anterior movement, while patients with SIGMA Knee implants did exhibit anterior sliding. This in vivo data is consistent with the computational and experimental results of Clary and colleagues. Dr. Takagi’s study was published in the Annals of Medicine and Surgery in March 2017. This content is intended for Health Care Professionals in the United States.