Ivan Puluj in the UK. While Professor Puluj's finding were essentially X-rays, he did not recognise them as such at first, although he demonstrated X-ray pictures of a hand and fingers obtained by using his tube / lamp to his students. This credit later went on to Wilhelm Conrad Röntgen. Once Roentgen visited Professor Puluj's laboratory and the latter presented one of his tubes to Roentgen. Roentgen went home and in his laboratory started to conduct experiments with Puluj's tube. Puluj also continued to do research with his X-ray tubes. On 8 February 1896, just 6 weeks after Röntgen presented his finding
Roentgen stereophotogrammetry are accurately measured and the three-dimensional position of the markers is reconstructed using software. The change in the position (translation and rotation) of the prosthesis markers relative to the bone markers is then determined. The reported accuracy of RSA ranges between 0.05 and 0.5 mm for translations and between 0.15˚ and 1.15˚ for rotations (95% confidence interval). New RSA techniques that avoid the need for attaching markers to the prosthesis have been introduced. Roentgen stereophotogrammetry Roentgen stereophotogrammetry (RSA) is a highly accurate technique for the assessment of three-dimensional migration and micromotion of a joint replacement prosthesis relative to the bone