自制异体骨腰椎间融合器的力学测评

目的 评价植入自制异体骨腰椎间融合器(异体骨cage)的腰椎节段的稳定性和生物力学性能.方法 将自制异体骨腰椎间融合器植入5具新鲜青壮年尸体标本的L4～L5椎间隙,进行抗弯、抗扭转和抗压缩测试,并与植入前和髓核切除后进行比较.结果 自制异体骨腰椎间融合器植入后,腰椎节段的屈曲和后伸的抗弯强度显著增加(P＜0.01),抗扭转强度也有较显著增加(P＜0.05).其压缩刚度比髓核摘除后高(P＜0.05) .结论 自制异体骨腰椎间融合器植入腰椎节段的稳定性提高.自制异体骨腰椎间融合器具有足够的支撑、维持或增加椎间隙高度的功能,椎间稳定性好,其设计符合椎间隙解剖学特点,可以达到生物力学和临床应用要求,但目前临床应用时仍需加用内固定.

Biomechanical testing and evaluation of a self-made allograft interbody fusion cage at lumbar spine

Objective To evaluate the stability and compressive mechanical functions of the lumbar spine following insertion of a new self-made allograft interbody fusion cage.Methods Anti-bending intensity with three points test,anti-rotation intensity and compressive stiffness were measured at L4-L5 lumbar spine on five adult human fresh cadaveric specimens following insertion of a new self-made allograft interbody fusion cage and compared with that of before and after nucleus pulposus removal.Results The anti-bending intensity of flexion and extension of lumbar spine after inserting a new allograft interbody fusion cage was increased significantly(P<0.01),and so did the anti-rotation intensity(P<0.05).The test also revealed that the compressive stiffness after inserting a new allograft interbody fusion cage increased significantly as compared with that of nucleus pulposus removal(P<0.05).Conclusion The new self-made allograft interbody fusion cage can sustain or increase the height of intervertebral space of the lumbar spine,provide enough support and improve the stability of the lumbar spine.Its design is distinctive and reasonable.It completely meets biomechanical and clinical requirements.