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 .
Fixation of Total Knee Arthroplasty Improved by Mobile-bearing Design
We examined the in vivo displacement of  mobile-bearing polyethylene  and its effect on prosthesis-bone fixation .  Thirty-five patients with the Interax ® ISA mobile platform total knee arthroplasties were examined by roentgen stereophotogrammetric analysis . Our protocol included weightbearing to measure the range of motion of the mobile platform in relation to the tibial component . We also studied the  micromotions of the tibial component in relation to the tibia during a 2-year followup . The analysis of micromotion ( maximum total motion mean , 0.5 mm ; subsidence mean , 0.15 mm ) showed this mobile platform design is stable and improves fixation at the prosthesis-bone interface . Longitudinal rotations of the mobile platform occurred in all patients and followed a homogeneous pattern of motion , depending on the examination . However , anteroposterior translations did not show any patterns with specific examination . This suggests the meniscal movement adapts itself to different weightbearing conditions . We measured the in vivo mobile-bearing displacement under static loading conditions . We also observed improved fixation at the bone-prosthesis interface
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 .