Periprosthetic bone mineral density after total knee arthroplasty

Objective:To evaluate the changes of periprosthetic bone mineral density(BMD) after total knee arthroplasty.Methods: Sixteen patients treated by cemented total knee arthroplasty were included in this study.The periprosthetic bone mineral density was measured by dual-energy X-ray absorptiometry 1 week,3 months,6 months and 12 months postoperatively.The periprosthetic bone of distal femur and proximal tibia were divided into four and three regions of interest separately,and the mean BMD was measured.Results: The mean BMD of all seven regions decreased within 12 months after operation(P0.05) and of distal femur and proximal tibia decreased by 15.73% and 15.16%,respectively.Bone loss was the most rapid during initial 3 months.Conclusions: The periprosthetic bone mineral density significantly decreases after total knee arthroplasty,which may be measured precisely by dual-energy X-ray absorptiometry.