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 .
Increase in early polyethylene wear after sterilization with ethylene oxideRadiostereometric analyses of 201 total hips
We evaluated polyethylene wear by measuring femoral head penetration in 201 THA ( median age 62 ( 31 - 81 ) years , 117 women ) extracted from 5 r and omized studies aim ed to assess various fixation principles . There were 30 cemented all-polyethylene Lubinus cups sterilized by gamma irradiation in a reduced oxygen environment , 65 porous-coated Trilogy cups with liners gamma-sterilized in inert gas . Moreover , 37 cemented cups were sterilized with ethylene oxide ( Reflection all-poly ) and 69 porous-coated cups had liners sterilized in ethylene oxide ( Reflection ) . 28 mm femoral heads were used in all cups . The patients were followed with repeated radiostereometric measurements ( RSA ) up to 2 years . The activity level of the patients was evaluated by a question naire . After 2 years , cups with polyethylene sterilized in EtO had almost twice the proximal and 3D penetration rates , as compared with gamma-sterilized polyethylene . The penetration did not differ between the gamma-irradiated design s. Using stepwise linear regression analysis , we found that the type of sterilization , age and weight were the most important predictors and that they determined the direction of the proximal penetration rate . Activity score , male gender and proximal migration of the cup had little effect . The accelerated wear observed with the EtO-sterilized polyethylene causes concerns about long-term problems and especially in younger patients
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 .