The effect of 6 months oral alendronate treatment on periprosthetic bone loss after total knee arthroplasty

This study was designed to test whether established post-total knee arthroplasty (TKA) bone loss at over 2 years post-surgery could be improved by 6 months of alendronate administration. This was a double blind randomized controlled trial. From a previous study assessing periprosthetic bone mineral density (BMD) at 2 years post-surgery, 11 patients were randomised to receive either 70 mg of alendronate per week or a placebo, for 6 months. DXA scans were performed on both knees (operated knee and contralateral knee) at 6 months and compared with pre-treatment DXA scans. No significant change in BMD following a 6-month administration of alendronate, given 2 years post-TKA was seen. Additionally, alendronate had no effect on Oxford Knee Scores. The administration of a 6-month course of alendronate has no significant effect on established periprosthetic BMD loss.