负重条件下不同髋臼假体表面骨整合情况评价(英文)

Bone osseointegration of various acetabular surfaces in weight bearing

背景:为了提高非骨水泥假体骨整合率,将羟基磷灰石(hydroxyapatile,HA)喷涂在不同假体表面上,并在狗体内进行试验,许多研究是在狗股骨部分非负重情况下使用,那么在狗的髋臼假体负重情况下骨整合情况如何呢?目的:通过对一组活体狗所实施的全髋关节置换手术模型,评价在负重情况下,不同髋臼假体表面骨整合情况。设计:以实验动物为研究对象,随机分组设计的观察对比研究。单位:北京同仁医院骨科,PathologyDepartment,BoneandJointLabora-tory,St.Michael'sHospital,UofT,Toronto,Canada。材料:实验于2001-10/12在加拿大St.Michael's医院病理科骨关节实验室完成。健康成年狗40条,体质量在29～44kg,雌雄不限,由加拿大安大略省兽医院提供。40条狗被分为7组,分别接受7种不同结构髋臼假体的全髋关节置换,包括,组1:等离子喷涂HA钛丝表面(AD/HA);组2:溶淀HA钴铬珠表面(CoCrbeads/PA);组3:钛珠表面(CPTibeads);组4:钛孔30PPI泡沫假体;组5:溶淀HA钛孔30PPI泡沫假体;组6:钛孔40PPI泡沫假体;组7:溶淀HA钛孔40PPI泡沫假体。方法:关节置换术后即开始关节负重,两周后自由活动。分别在3个月和6个月时将狗杀死,并取出髋臼假体和部分骨组织,制成病理片,依靠组织形态计量学方法,将髋臼假体分为负重区和非负重区,并对假体表面骨?

BACKGROUND:In order to enhance the rate and degree of osseointegration of ceme ntless implants,hydroxyapatile(HA) was applied on the different prosthesis surfa ces.The majorities of these studies have utilized non weight bearing in vivo d og models and have focused on the fixation of the femoral component.What is the osseointegration of macrotextured acetabular components in a weight bearing mod el(dog) like? OBJECTIVE:To evaluate the various macrotextured surface coatings applied to ac etabular components of the same design in a weight bearing canine total hip rep lacement model. DESIGN:Randomized comparative study using the experimental animals as subjects SETTING:Department of Ortopaedics,Beijing Tongren Hospital; Pathology Departme nt,Bone and Joint Laboratory,St.Michael's Hospital,U of T,Toronto,Canada MATERIALS:The experiment was completed in the Pathology Department,Bone and Jo int laboratory,St.Michael's Hospital,U of T,Toronto,Canada from October 2001 to December 2001.Acetabular components with the selected surface characteristics we re implanted into forty dogs with the body mass of 29-44 kg of either gender an d divided into seven groups, including group 1(AD/HA),Group 2 (CoCr beads/PA),Gr oup 3 (CPTi bead surface),Group 4 (CPTi 30 PPI foam),Group 5(CPTi 30 PPI/PA foam ),Group 6(CPTi 40 PPI foam),Group 7(CPTi 40 PPI/PA foam). METHODS:Exercise was restricted to leash walks for the first fourteen days pos t operatively.After this,dogs were allowed unrestricted activity.The dogs were euthanized at either three or six months after surgery as the project's protocol .The whole acetabulum,divided into weight bearing and non weight bearing area s,containing the component was harvested and submitted for histological and his tomorphological assessment. MAIN OUTCOME MEASURES:The bone ongrowth and ingrowth with weight bearing and w ithout weight bearing areas in each group. RESULTS:There was significantly greater bone apposition and bone ingrowth for implants with HA coatings as compared to uncoated implants.There was also signif icantly greater bone ingrowth in weight bearing areas as compared to non weight bearing areas at both time periods.The bone growth into AD/HA was 17%at 3 mon ths and descended to 14%at 6 months.The bone growth into CPTi beads surface was 21%at 3 months,30%at 6months in weight bearing areas.All four foam coating surfaces there were 15%to 21%ongrowth at 3 months,15%to 32%at 6 months and 2 1%to 32%ingrowth at 3 months,29%to 45%at 6 months in weight bearing areas( P< 0.05). CONCLUSION:Hydroxyapatite coating produces significantly greater bone ingrowt h and apposition in all the surface treatments tested in this study.Weight beari ng produces a greater bone ingrowth than non weight bearing areas and obviously increases with the time prolonging,especially the foam coating