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 .
Differences in stability and bone remodeling between a customized uncemented hydroxyapatite coated and a standard cemented femoral stem A randomized study with use of radiostereometry and bone densitometry.
The custom made Unique stem is design ed to fit closely to the metaphyseal region of the femur in order to obtain maximum mechanical stability and optimal load transfer . Thirty-seven patients ( 38 hips ) with non-inflammatory arthritis were r and omized to the uncemented custom made Unique stem or the Elite Plus stem inserted with cement . The patients have been followed clinical ly as well as with radiostereometry ( RSA ) and Dual-energy X-ray Absorptiometry ( DXA ) for 2 years . After 2 years the RSA result showed minimal translation and rotation for the Unique stem while the Elite Plus rotated slightly ( mean 1.05 degrees ) into retroversion . Compared to previous studies the Elite Plus was as stable as the Charnley prosthesis . The DXA results showed a significantly higher proximal and total ( 10 % for the Unique versus 5 % for Elite ) bone loss for the Unique stem compared to the Elite Plus . Thus the optimal proximal press-fit of the custom made stem did secure a stable fixation , but did not decrease the proximal bone loss
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 .