Roentgen Stereophotogrammteric Analysis

  Picture of Roentgen Stereophotogrammetric Analysis (RSA)

(https://www.researchgate.net/figure/Radiostereometric-analysis-RSA-images-with-computer-aided-design-CAD-model-during_fig1_353956389)

How it works ?

With two D X-ray images , determines 3 D co-ordinates of an object within the calibration cage from two 2 D X-ray image. 

uses 

    measures migration over time of joint replacements or the implant stabilized in one point.