A fluoroscopy-based system/method for correcting at least an inclination angle of an acetabular cup during total hip arthroplasty. A computing device processes an image of the surgical area to determine distortion, at least as a function of the reference object in the image. Thereafter, the computing device generates a correction factor and measures an inclination angle of an initially positioned acetabular cub in an anterior posterior image of a patient's pelvis, and corrects, as a function of the correction factor, the measured inclination angle to provide an accurate inclination angle of the acetabular cup.