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 .
Migration of the acetabular component: Effect of cement pressurization and significance of early radiolucency
Background Cementing technique is a crucial factor in prosthesis fixation . No r and omized studies have been published , however , comparing the outcome of conventional fingerpacking with the outcome of pressurization of the cement prior to cup insertion . Patients and methods We r and omized 50 THAs to either fingerpacking or sequential pressurization ( including individual pressurization of each anchorage hole ) and followed the patients with RSA for 5 years . The penetration of cement into the anchorage holes was measured on digital radiographs . Postoperative radiolucent lines around the cup were correlated to later RSA results . For clinical evaluation , we used SF-36 and HHS . Results The pressurized group of THAs was more stable regarding changes in inclination . We found no other difference in the migratory behavior . The cement penetration into the anchorage holes was deeper with the pressurization technique than with fingerpacking . For the whole group taken together , there was a strong relation between the presence of radiolucent lines as measured on the postoperative radiograph and later migration observed by RSA at 2 and 5 years . Interpretation Pressurization of the cement produced better cement penetration and increased the cup stability in terms of changes in inclination . Early findings of radiolucent lines can predict later unfavorable cup migration
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 .