同种异体骨支撑架结合自体骨和DBM治疗股骨头坏死的生物力学研究

Biomechanical study on treatment of sheep femoral head necrosis by implanting composite of allogeneic bone support frame,autologous bone anddecalcified bone matrix

[目的]研究同种异体骨支撑架结合自体骨和脱钙骨基质(decalcified bone matrix,DBM)植入治疗股骨头坏死生物力学变化。[方法]建立羊双侧股骨头坏死模型,4周后分为4组:单纯行髓芯减压组(A组)、髓芯减压后植入自体松质骨和OSTEOSET(2DBM组(B组)、髓芯减压后植入同种异体骨支撑架/自体松质骨OSTEOSE(2DBM组(C组)和正常对照组。术后分别于5、10、20周对股骨头行影像学、组织学观察和生物力学测定。[结果]影像学和组织学检查结果显示C组在髓芯减压区骨缺损修复及成骨方面较B组略高,B、C两组都较同时期的A组明显增强。生物力学测试结果表明,术后5、10、20周时C组力学强度较A、B两组明显增高,差异有统计学意义(P<0.05),在10、20周时C组股骨头生物力学强度和正常股骨头己无明显差异。[结论]应用同种异体骨支撑架结合自体骨和脱钙骨基质治疗股骨头坏死,能有效加强股骨头的力学结构,促进坏死骨的修复,防止股骨头关节面的塌陷。

[ Objective]To study the biomechanical changes of the treatment of sheep femoral head necrosis by implanting a composite of allogeneic bone support frame, autologous bone and decalcified bone matrix. [ Method] From Oct. 2005 to Jul. 2006 ,twenty-two big-tail sheep were used in the experiment. Two sheep served as the control group without any treatment. In twenty sheep, the animal models of femoral head necrosis were createdby ligating the lateral and medial femoral circumflex arteries and injecting pure alcohol into femoral head. Four weeks after surgery, two sheep models were detected, other eighteen sheep were treated with core decompression and randomly divided into three groups： Group A were left without any treatment, Group B were treated with implanting a composite of autologous bone and decalcified bone matrix and Group C were treated with implanting a composite of allogeneic bone support frame, autologous bone and decalcified bone matrix. Imageology, histological examinations and biomechanics test were performed at 5, 10,20 weeks after implantation. [ Result] Inspection of histological and imageology revealed more bone forming and healing in group B and C than those in Group A. The biomechanics test showed the biomechanical properties of the femoral head in Gronp C were significantly superior to those in the Group A and B （P 〈 0.05） , 10 weeks after implantation, they approached to the normal biomechanical stability. [ Conclusion ] Implanting a composite of allogeneic bone support frame, autologous bone and decalcified bone matrix not only can enhance the repairing procedure but also can restore the biomechanical properties of the femoral heads.