Determining Effects Of The Tibial Hemiarthroplasty UnispacerTm Knee System On Human Cancellous Bone

摘要

The Unispacer? knee system is a medial compartment implant made from a cobalt chrome alloy shaped to mimic the medial tibial condyle. The geometry allows for articulation with the femur and works on the "mobile bearing" principle. It was developed as an alternative to unicompartmental components to avoid wear and osteolysis and to delay total knee replacement (TKR). The purpose of this research is to determine the possible effect that the implant may have on the mineral content and bone volume of the tibial plateau of the implanted medial compartment. The objectives of this study were to determine possible differences in bone mineral and volume of the proximal cancellous bone near the calcified zone of the articular cartilage and cancellous bone 3 mm distal. The null hypothesis tested was that the mineral content at the proximalbone (periprosthetic) beneath the implant would be the same as the mineral content at the cancellous bone 3 mm away. In addition, another null hypothesis tested was that the mineral content and bone volume of the proximal cancellous bone in the medial compartment would be the same as the proximal bone of the lateral compartment.