Biomechanical studies on gradient hydroxyapatite-coating / 中国矫形外科杂志

ABSTRACT

[Objective]To evaluate the interface biomechanical characteristics of a new kind of hydroxyapatite coating.[Method] Ten dogs underwent hermiarthroplasty of hip joint and were divided into 2 groups.One group was placed in Ti-6AI-4V femoral stem(Ti hip group),the second group was placed in HA-coated femoral stem(HA hip group).The second method was rod implant in condyles in both legs of each dog.Four matured dogs were selected.Eight Ti-6AI-4V rods(Ti rod group)were placed in lateral and medial condyle in left leg of each dog and eight HA-coated rods(HA rod group)were implanted in that of right leg of each dog.The dogs were sacrificed at 12 weeks after operation,and then the interface shear strength and imerface histological changes were evaluated.[Result]The Pust-out test showed that the average interface shear strengths of Ti hip group and HA hip group were(2.58?1.56)Mpa and(7.57?1.03)Mpa respectively.The interface shear strengths of HA hip group was significantly higher than that of Ti hip group(P