Early Post-operative Changes in Bone Mineral Density following Total Knee Replacement in Dogs

INTRODUCTION Stable long-term fixation in cementless total knee replacement (TKR) depends on the development and maintenance of adequate trabecular bone around the prosthesis. Since bone mineral density (BMD) values are predictive of the mechanical properties of bone, the measurement of BMD has emerged as an important and potentially valuable means of assessing the effects of total joint replacement on periprosthetic bone. Although most of the published work to date has focused on hip replacement, a number of studies have documented significant (up to 1020%) decreases in BMD within the first 12 months post-TKR [1, 2]. The specific aims of this study were (1) to determine the precision (i.e. reproducibility) of DEXA in a canine model of cementless TKR, (2) to quantify early changes in BMD following TKR and (3) to investigate whether bone loss following TKR could be prevented by local application of an anabolic growth factor, osteogenic protein-1 (OP-1).