WHAT WORKS BEST, A CEMENTED OR CEMENTLESS PRIMARY THR? 20 YEAR RESULTS OF A RCT

Aim The purpose of this study was to perform a randomised controlled trial (RCT) to compare the >20 year outcomes of cemented versus cementless Mallory Head total hip replacements (THRs). Methods Two hundred and fifty patients with unilateral osteoarthritis of their hip, a mean age of 64 years and 48% of whom were female were randomised to receive either a cemented (n=124) or cementless (n=126) THR. Results At >20 years follow-up, the cementless Mallory Head THR outperformed its cemented counterpart in terms of overall Kaplan Meier survivorship (p=0.01), socket survivorship (p=0.009) and stem survivorship (p 65 - 12% versus 65 - 19% versus 65 - 0% versus 65 - 16% versus Conclusion This RCT has demonstrated that cementless THRs offer significantly better overall, socket and stem survivorships at 20 or more years. The cementless tapered femoral stem performed particularly well with 100% survivorship at 20 years, excluding infections. Caution should be taken in generalising these results to other cemented and cementless THRs.