INTERPRETATION The guidelines have improved method ological reporting in RSA studies , but adherence to these guidelines is still relatively low .
BACKGROUND AND PURPOSE Guidelines for st and ardization of  radiostereometry ( RSA )  of implants were published in 2005 to facilitate comparison of outcomes between various research groups .
In this systematic review , we determined how well studies have adhered to these guidelines .
A randomised RSA study of Peri-Apatite HA coating of a total knee prosthesis.
BACKGROUND In total knee replacement , sound early fixation of the prosthesis is crucial for achieving a good long-term result and for minimising the risk of loosening . Various types of prosthetic material , different surface textures and shapes and the incorporation of screws or pegs have been used to achieve good fixation , particularly in the uncemented knee . Hydroxyapatite ( HA ) coating of prosthetic joint components is another technique used to enhance early stability and so to improve the longevity of the prosthesis-bone fixation . HA ceramic coatings are mostly plasma sprayed onto the fixation surface of the implant . Plasma spraying is largely a ' line of sight ' technique and as such there are difficulties involved when covering three-dimensional planes , such as porous beaded fixation surfaces typically found on several knee prostheses . The objective of this study was to assess the clinical performance of the solution-deposited HA coating , Peri-Apatite , with regard to its ability to stimulate an endurable and stable implant fixation . PATIENTS AND METHODS We r and omised 60 patients into two groups ; one group received the porous coated prosthesis with solution-deposited HA  , and the other group received a prosthesis without HA . Radiostereometric examination was used as the primary tool for measuring migration in the prosthetic components . RESULTS There was a lower incidence of early subsidence in the Peri-Apatite group . At 24 months there were no differences in clinical scorings or maximal total point motion . CONCLUSION Addition of solution-deposited HA coating appears to provide better early stable fixation in a porous coated knee prosthesis
INTERPRETATION The guidelines have improved method ological reporting in RSA studies , but adherence to these guidelines is still relatively low .
BACKGROUND AND PURPOSE Guidelines for st and ardization of  radiostereometry ( RSA )  of implants were published in 2005 to facilitate comparison of outcomes between various research groups .
In this systematic review , we determined how well studies have adhered to these guidelines .