Research progress of biomechanics and finite element analysis of lumbar interspinous devices / 中国组织工程研究

ABSTRACT

BACKGROUND:The lumbar interspinous device, as a kind of non-fusion technology has been extensively applied in the clinic and exerts superiority in biomechanics compared with the traditional fusion technology. With the development of prosthesis design and impanation technology, it reveals a better application prospect. OBJECTIVE:To review the biomechanics and finite element analysis of lumbar interspinous devices. METHODS:The first author retrieved the databases of CNKI, WanFang, PubMed and SpringerLink using the keywords of“lumbar spine, interspinous devices, biomechanics, finite element analysis”in Chinese and English, respectively. Researches related to the biomechanics and finite element analysis of lumbar interspinous devices were included and repeated researches were excluded. A total of 44 literatures were enrol ed for review, including 8 Chinese and 36 English literatures. RESULTS AND CONCLUSION:(1) Biomechanical y, several interpinous devices, which are commonly used in the clinic, can increase the stability of the implanted segment in sagittal alignment by limiting the range of flexion-extension, with no significant change in lateral bending and axial rotation. (2) Few studies analyze the influence of the implant size and placement on the implanted segment and on the adjacent segments. (3) Through the stress nephogram, three-dimension finite element analysis can intuitively analyze the changes of the stress distribution in the intervertebral disc, isthmus and facet joints before and after implantation. Both biomechanical studies and finite element analysis indicate that interspinous devices can share the load of the disc and facet joints, and at the same time, make no effect on the range of motion and stress of the adjacent segment. (4) In conclusion, the short-term biomechanical advantage of the interspinous devices is obvious, but further studies are needed. The finite element analysis can simulate different body physical environment, and can analyze mechanical distribution changes after implantation, which is an effective way to evaluate the mechanical mechanism of the interspinous devices.