Effect of Local Pamidronate in Preventing Bone Loss After Total Hip Arthroplasty

The aims of the study are to determine whether pamidronate applied locally causes diminished periprosthetic bone loss and decreased rate of bone turnover compared to patients receiving placebo after cemented total hip arthroplasty (THA). The study design will be prospective, randomized, and blind. Periprosthetic bone mineral density (BMD) will be measured with dual energy X-ray absorptiometry (DXA) at the total periprosthetic area as well as at seven Gruen zones or regions of interest. DXA scans will be performed at one week (baseline), three months, and six months postoperatively. Mean values of biochemical markers of bone turnover, BMD, and baseline-normalized BMD values will be compared between the bisphosphonate and placebo groups at each time point. For all temporal measurements including bone markers, BMD and normalized BMD, mean values will be compared across each time point within a given group.