Compression in the Human Spine

Notable Features of Model

• Based on in vivo patient data
• Segmentation and mesh generation of complex structures
• Multi-part model

Purpose of the Study

Work related injuries to the spine are becoming more commonplace in the UK with over one million people suffering from work induced musculoskeletal disorders of the lower back, each year. New image processing and mesh generation techniques can now aid in the analysis of such biological structures, particularly where the geometry is complex. Novel proprietary techniques have been developed for the automatic generation of volumetric meshes from 3D image data including image datasets of complex structures composed of two or more distinct materials.

Segmentation in ScanIP

Details of the mesh (more detailed image)

FEA - compressive strain

Segmentation and Mesh Generation in ScanIP and ⁺ScanFE

A 3D volumetric FE mesh of the human lumbar spine was generated from in vivo high resolution MRI scan data of 1mm x 1mm in-plane and 1mm slice-to-slice separation. The anatomical details segmented in the model include five vertebrae, the annulus fibrosus, nucleus pulposus and the cartilaginous end plates. A mesh of 535,610 elements was generated in ⁺ScanFE in just twenty minutes, and contact surfaces were automatically created within at the surface of the vertebrae between the superior and inferior articular processes.

FE Analysis in ABAQUS

A fixed boundary condition was imposed on the lower end of the model, and a compressive strain was applied to the top of the spine in order to simulate a healthy young adult carrying a heavy load. The FE analysis took just under two hours on a PC and the results show the individual pressure response of the components of the spine.