Randomised clinical trial assessing migration of uncemented primary total hip replacement stems, with and without autologous impaction bone grafting.

PURPOSE: Uncemented stems in primary total hip replacement (THR) are concerning in the elderly due to ectatic femoral canals and cortical thinning resulting in higher incidence of fracture and subsidence in this population. To obviate this concern, the authors developed a technique using autologous impaction bone grafting to achieve a better fitting femoral stem. The aim of this randomised clinical trial was to assess the efficacy of the technique. METHODS: From 2013 to 2015, a total of 98 consecutive participants (100 primary THR procedures) were inducted into a single-institution, single-blinded, randomised clinical trial assessing, with radiostereometric analysis (RSA), the efficacy of autologous impaction bone grafting in uncemented primary THR compared with traditional uncemented primary THR technique. The primary outcome measure was femoral component migration using RSA. Secondary outcomes were post-operative proximal femoral bone density (using DEXA), hip function and quality of life using Oxford Hip Score (OHS) and Short Form-12 Health Survey (SF-12), hip pain and patient satisfaction. RESULTS: There was no difference in femoral component stability (p > 0.5) or calcar resorption between the Graft and No Graft Groups at two years. There was also no difference in OHS, SF-12, pain or satisfaction between the Graft and No Graft Groups at two years (p > 0.39). CONCLUSIONS: Autologous impaction bone grafting in uncemented primary THR has shown its short-term post-operative outcomes to be equivalent to standard uncemented technique, whilst offering a better fit in patients who are between femoral stem sizes. AUSTRALIAN CLINICAL TRIAL REGISTRATION NUMBER: ACTRN12618000652279.

Prospective randomised clinical trial assessing subsidence and rotation, using radiostereometric analysis, of two modular cementless femoral stems (Global K2 and Apex).

AIMS: To accurately assess subsidence, rotation and clinical scores in two cementless femoral stems. METHODS: 260 patients received either K2 or Apex femoral stems and were studied over 2y, with RSA and clinical scores. RESULTS: Mean Oxford Hip score for both stems was excellent (45.78 and 46.76). Very little subsidence or rotation were noted on RSA in either stem. There were no statistically significant differences in clinical scores, or radiological motion between stems. Revision rate was 0.8% over the study period. CONCLUSION: Excellent clinical and RSA scores over the 2y study period predict good long term outcomes for these stems.