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 .
Increased bone turnover as reflected by biochemical markers in patients with potentially unstable fixation of the tibial component
Introduction Whether biochemical markers of bone metabolism can be used in assessing the conditions of implant fixation is unknown . In this study , the serum levels of three bone markers were measured prospect ively in patients undergoing total knee arthroplasty ( TKA ) to determine if patients with different fixation conditions of the tibial component showed any differences in the levels of the markers . Material s and methods The fixation of the tibial component in 40 knees ( 40 patients , 14 male and 26 female , average age 71 years ) was assessed by radiostereometric analysis ( RSA ) , and based upon the pattern of migration , implants with stable fixation ( n=25 ) and potentially unstable fixation ( n=15 ) were identified . Serum levels of carboxyterminal propeptide of type I procollagen ( PICP ) , osteocalcin ( OC ) and cross-linked carboxyterminal telopeptide of type I collagen ( ICTP ) were assessed and compared between the two fixation groups . Blood sample s were obtained preoperatively ( baseline ) and repeated postoperatively at 1 week , 3 , 6 , 12 , and 24 months . Results The baseline levels of the markers were statistically the same ( p>0.05 ) between the two fixation groups . Postoperatively , ICTP levels in the unstable group were significantly higher than in the stable group from 6 to 24 months ( p=0.02 ) . Levels of OC in the unstable group were higher at 12 and 24 months compared with the stable group , reaching statistical significance only at 12 months ( p=0.03 ) . No difference in the levels of PICP was found between the two groups . Conclusion The findings indicate a more active bone turnover probably at the bone-cement/implant interface in knees with potentially unstable fixation . It reveals the potential value for biochemical markers in monitoring implant fixation and aseptic loosening and suggests a possibility for improving implant fixation by drugs which inhibit osteolysis
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 .