Radiostereometric Analysis (RSA) is a technique applied in orthopaedics to measure the three-dimensional movements and migratory patterns of a prosthetic device. As early implant micromotion has been highlighted as a predictor for later loosening, RSA provides insight into the stability and long-term survivorship of each device.
RSA requires the intra-operative placement of tantalum markers in the surrounding bone and on the prosthesis. Post-operative radiographic follow-up entails the use of a calibration cage and two simultaneous x-rays to expose the joint and identify its relative position, allowing the measurement of movement of one kinematic body to another, over time.
IMRI has the capability to offer RSA in a clinical setting by providing the structure, development and implementation of an RSA study, followed by the scientific analysis and interpretation of RSA data. RSA is regarded as a valuable tool and currently employed in all prosthesis studies undertaken at IMRI.