人工股関節置換後にチタン基インプラントより生じた応力遮蔽にともなうと卜大腿骨の骨損失および骨質劣化

摘要

The present work was aimed at understanding the stress-shielding caused by hip-joint implantation into a femur by using a human cadaver with a cementless hip implant. In particular, bone quality was assessed from the standpoint of preferential c-axis orientation of biological apatite (BAp). Comparing the implanted side to the non-implanted side, a finite element analysis (FEA) indicated that artificial hip-joint implantation had a significant stress-shielding on the femur. The results also showed a remarkable decrease in the degree of preferential BAp orientation as well as bone loss in Haversial canal in the medial-proximal femur. This is the first report showing a reduction in the degree of preferential BAp orientation due to a stress-shielding after artificial hip-joint implantation. Since preferential BAp orientation is an important parameter for determining bone mechanical function, these findings should be taken into account in future artificial hip-joint designs, especially those involving the stem component.%人工膜関節置換術（Total Hip Replacement：THR）は，変形性関節症や関節リウマチなどの重度の骨・関節疾患によって失われた股関節機能の再建のために不可欠な整形外科技術の一つである. THRの施術件数は世界的に年々増加しており，USでは2006年のTHR施術数は231，000件に達している. 一方で，人工股関節の埋入によって，周囲大腿骨の骨吸収により骨強度が低下し，その結果として，骨折が高い確率で生じている.