Changes of femoral periprosthetic bone mineral density 6 years after treatment with alendronate following total hip arthroplasty

49 patients who had undergone total hip arthroplasty (THA) were randomized to a postoperative bisphosphonate (oral alendronate) treatment group or to a non-treatment group, to assess the effect of bisphosphonate on bone mineral density (BMD) and bone loss. Results from this study indicated that there was a significant increase in BMD from the 1-year to the 6-year follow up in Gruen region 5 of the control group and Gruen region 6 of the 20 mg alendronate subgroup. There were no differences in BMD values from the 1-year to the 6-year follow-up in every other Gruen region for all groups, maintaining the positive effects of the 1-year follow-up. Lastly, there was no difference in clinical outcomes between the treatment and control groups.