Abstract:
Introduction Triggering the immune system via antigenic stimulation at the time of spinal fusion surgery may enhance bone morphogenesis and result in successful bony arthrodesis. We sought to demonstrate that bone morphogenesis could be enhanced via antigenic immunologic stimulation of a surgical fusion site. Methods New Zealand white rabbits underwent non-instrumented posterolateral fusion of L5-6 with implantation of either an immunologically activated graft (inert beta-tricalcium phosphate) or harvested autograft. Fusion was evaluated using plain radiographs, micro-computed tomography (CT), mechanical palpation, and biomechanical testing. The final evaluation was carried out at 12 weeks postoperatively. Results Eight rabbits received immunologically activated grafts; 10 received autografts and served as historical controls. Fusion rates were identical between groups (both 50%). Radiographs and micro CT of the fusion mass showed no significant difference between groups, and both showed good incorporation of the transverse processes into the fusion masses with radiographic evidence confirming trabeculation and bone remodeling. However, mechanical testing of the fusion sites showed superior fusion strength in the rabbits that received immunologically activated grafts, approaching a factor of two on flexion/extension, lateral bending, and axial rotation. Little to no graft material was appreciable in the non-fused antigen-treated specimens. Conclusions There is a long-standing need for a graft material that can replace autograft bone, due to the negative clinical consequences and financial costs pertaining to autologous bone harvesting. No allograft bone substitute to date has been able to reliably replicate the success of harvested autograft bone. This study suggests that immunological enhancement of inert beta-tricalcium phosphate can potentially be a substitute for allograft bone that can meet and even exceed the success of harvested autograft bone.
摘要:
引言在脊柱融合手术时通过抗原刺激触发免疫系统可能会增强骨形态发生并导致成功的骨关节固定术。我们试图证明可以通过手术融合部位的抗原免疫刺激来增强骨形态发生。方法新西兰白兔进行非仪器化的L5-6后外侧融合,植入免疫活化移植物(惰性β-磷酸三钙)或收获的自体移植物。使用平片评估融合,显微计算机断层扫描(CT),机械触诊,和生物力学测试。最终评估在术后12周进行。结果8只兔子接受了免疫激活的移植物;10只接受了自体移植物,并作为历史对照。组间融合率相同(均为50%)。融合肿块的X线片和显微CT显示组间无显著差异,两者均显示横突良好地结合到融合块中,影像学证据证实了小梁形成和骨重建。然而,融合部位的机械测试表明,接受免疫激活移植物的兔子具有优异的融合强度,在屈曲/伸展上接近2倍,横向弯曲,和轴向旋转。在未融合的抗原处理的标本中几乎没有或没有移植材料。结论长期需要一种可以替代自体骨的移植材料,由于与自体骨采集有关的负面临床后果和财务成本。迄今为止,尚无同种异体骨替代品能够可靠地复制已收获的自体骨移植的成功。这项研究表明,惰性β-磷酸三钙的免疫增强可能是同种异体移植骨的替代品,可以达到甚至超过收获的自体移植骨的成功。