新型可盘旋型人工髓核假体的弹性与黏弹性能测试  

Compression and creep properties of a spiral nucleus pulposus prosthesis

作　　者：张嘉利[1] 马远征[2] 朱微[3] 高瑾[3] 杨达宇[2] 王天天[2] 

机构地区：[1]山西医科大学研究生院,太原030001 [2]中国人民解放军第309医院骨科,北京100091 [3]北京科技大学材料科学与工程学院,北京100083

出　　处：《中国骨与关节外科》2013年第2期177-181,共5页Chinese Journal of Bone and Joint Surgery

摘　　要：背景:既往人工髓核置换治疗椎间盘退行性疾病时,由于假体移位、纤维环损伤、终板损伤等并发症,临床应用受到限制。而后推出的可注射性人工髓核则有生物毒性、液体渗漏、热损伤及弹性模量不佳等缺点。我们研制了一种在微创条件下置入的自盘旋型人工髓核假体。目的:本实验旨在对可盘旋型聚乙烯醇(PVA)水凝胶髓核假体进行生物力学性能测试,对比研究其与正常髓核的差异。方法:制备两组PVA含量不同的水凝胶试样,各4件备用,大小均为30mm×20mm×5mm,PVA含量分别为15wt%和20wt%。取新鲜成人腰椎脊柱标本10件,制作成脊柱功能单元(L4-L5)。将其中8件标本分别置入两组试样。使用电子万能材料试验机进行单轴向压缩试验和蠕变试验,将结果以图表的形式输出,用SPSS14.0软件对3组结果组间比较行单因素方差分析。结果:应力应变曲线和蠕变曲线均显示PVA含量为15wt%和20wt%的两组假体与正常髓核变化趋势类似,且含量为20wt%组与正常组更为接近。统计学分析表明各组间两两比较差异有统计学意义(P<0.05)。说明这两组假体与正常髓核具有类似的弹性和黏弹特性。结论:这种新型的聚乙烯醇水凝胶假体的生物力学性能与正常髓核接近,在低应变时刚度较小,能够恢复脊柱的柔韧性;高应变时刚度较大,能够有效维持椎间隙高度,提供脊柱以稳定性,基本代替正常髓核行使其作用,恢复脊柱原有的生理功能。同时还可以为该假体下一步的研制和临床试验提供理论依据。Background： In recent years, the prosthetic nucleus pulposus technology develops by leaps and bounds. It includes pre-fabricated and injectable prosthetic nucleus pulposus. However, the former will damage the annulus fibrosus and cartilage endplate. The latter shortcomings are liquid monomer leak, heat damage and low rigidity. In order to avoid the above shortcomings, we develop a spiral artificial nucleus pulposus prosthesis. Objective： The purpose of this project is to do preliminary biomechanical research of the spiral prosthetic nucleus pulposus, and compare the prosthesis with physiological nucleus. Methods： The size of PVA hydrogel prepared was 30 mm×20 mm× 5 mm. The content of PVA was 15wt% and 20wt% in two kinds of PVA hydrogel. Ten L4-5 functional spinal units （FSU） from fresh adult cadavers were used in the test. Under three different conditions （control group and the two different groups of prostheses after implantation）, the characteristics of compression and creep were analyzed by the electronic universal material testing machine. Results： The stress-strain and creep curves of the FSU in the control group and two prostheses groups showed that the trends of the replaced disc were similar to that of the intact discs. The result of 20wt% group was closely consistent with the control group. Conclusions： This spiral prosthetic nucleus pulposus is a promising material for artificial nucleus pulposus. Similar with the intact discs, the two kinds of nucleus prostheses have a good compression and creep characteristics. Our research can supply reference for the development of new prosthetic nucleus pulposus.

关 键 词：人工髓核 聚乙烯醇水凝胶 盘旋 生物力学 压缩性能 蠕变性能 

分 类 号：R318.1[医药卫生—生物医学工程]