Clinical Study Of Periprosthetic Bone Mineral Density After Total Knee Replacement

Objective: To observe and analyze the change of periprosthetic bone mineral density (BMD) after total knee replacement with dual-energy x-ray absorptiometry.Methods: Twenty patients treated by cemented total knee replacement were included in the study. The periprosthetic bone mineral density was measured by dual-energy x-ray absorptiometry 7 days, 3 months, 6 months and 12 months postoperatively. The mean age of the patients at the time of the operation was 67. 5 years (ranged 65~78 years). Four of twenty cases were male, sixteen of twenty cases were female. The study population comprised patients with primary knee osteoarthritis (n=11) , posttraumatic knee osteoarthritis (n=5) and rheumatoid arthritis(n=4).All patients were free from all medications known to influence bone mineral metabolism and metabolic bone disease throughout the follow-up period. All patients underwent cemented total knee replacement without patella replacement. All the prosthesis were made by the same corperation. After the follow-up of 12 months, the patients' function of knee after operation was appraised by the HSS Knee Score. The periprosthetic bone of distal femur was divided into four regions of interest (ROI I～ROI IV) and the bone around the proximal tibia was divided into three regions of interest (ROI 1～ROI 3). The bone mineral density (BMD) were measured by dual-energy x-ray absorptiometry (DEXA).The mean bone mineral density (BMD) was analysed with one-way...