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 .
Bone morphology in relation to the migration of porous-coated anatomic knee arthroplasties : a roentgen stereophotogrammetric and histomorphometric study in 23 knees.
The quality of the subchondral bone in total knee arthroplasty ( TKA ) may be important for the outcome . We correlated a histomorphologic analysis of the prosthetic bone bed to micromotion as analyzed by  roentgen stereophotogrammetric analysis ( RSA ) .  Twenty-three knees , both osteo- and rheumatoid arthritic were studied . The mean migration after 1 year was 1 mm ( 0.21 - 2.68 ) , with no correlation to the bone variables or diagnosis . One patient underwent revision after 3 years because of pain . One patient underwent revision after 15 years because of aseptic loosening . This patient appeared stable according to changes in maximum total point motion ( MTPM ) , but the prosthesis migrated continuously according to segment motion . Prosthetic migration increased after 10 years , zones started to evolve , and the patient became symptomatic after 13 years . A biopsy of the bone bed was taken in all patients . A larger percentage of trabecular bone and a larger relative area of unmineralized osteoid surface were found in patients with rheumatoid arthritis compared with those with osteoarthritis . The latter finding is probably a result of increased bone turnover . In conclusion , no support currently exists for the idea that preoperative bone quality , evaluated as bone histomorphometry , has any impact on prosthetic micromotion in knee prostheses
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 .