Medical & Biological Engineering & Computing

, Volume 57, Issue 1, pp 89–98 | Cite as

Finite element analysis and design of an interspinous device using topology optimization

  • Li-Xin GuoEmail author
  • Jia-Yu Yin
Original Article


Recently, interspinous stabilization with Coflex-F implant has become an alternative to treat lumbar spinal stenosis (LSS). However, little attention focused on modifying the structure of the device to obtain the better clinic application. The purpose of this study was to design a new interspinous implant using topology optimization methods and evaluate its biomechanical performance. The finite element models of healthy lumbar spine and surgical lumbar spine with Coflex-F and Coflex-NEW (the new designed implant) were constructed. Finite element analysis was applied to each of the three models. The interspinous implant structure after topology optimization was remodeled at an 8% reduced volume compared with the Coflex-F device, and they can both provide stability in all motion at the surgical segment. Additionally, the advantage of Coflex-NEW was that it can decrease the von Mises stress of the implant structure in flexion, extension, torsion, and the spinous process in flexion, extension, and bending. The stress in spinous process with Coflex-NEW was well-distributed.

Graphical abstract


Coflex-F Topology optimization Lumbar interspinous implant Finite element analysis Spine Biomechanics 


Funding information

This study was supported with grants from the National Natural Science Foundation of China (51275082, 11272273).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© International Federation for Medical and Biological Engineering 2018

Authors and Affiliations

  1. 1.School of Mechanical Engineering and AutomationNortheastern UniversityShenyangChina

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