Biomechanical study of different bone cement distribution on osteoporotic vertebral compression Fracture-A finite element analysis.

PURPOSE: This study aimed to compare the biomechanical effects of different bone cement distribution methods on osteoporotic vertebral compression fractures (OVCF).

PATIENTS AND METHODS: Raw CT data from a healthy male volunteer was used to create a finite element model of the T12-L2 vertebra using finite element software. A compression fracture was simulated in the L1 vertebra, and two forms of bone cement dispersion (integration group, IG, and separation group, SG) were also simulated. Six types of loading (flexion, extension, left/right bending, and left/right rotation) were applied to the models, and the stress distribution in the vertebra and intervertebral discs was observed. Additionally, the maximum displacement of the L1 vertebra was evaluated.

RESULTS: Bone cement injection significantly reduced stress following L1 vertebral fractures. In the L1 vertebral body, the maximum stress of SG was lower than that of IG during flexion, left/right bending, and left/right rotation. In the T12 vertebral body, compared with IG, the maximum stress of SG decreased during flexion and right rotation. In the L2 vertebral body, the maximum stress of SG was the lowest under all loading conditions. In the T12-L1 intervertebral disc, compared with IG, the maximum stress of SG decreased during flexion, extension, and left/right bending and was basically the same during left/right rotation. However, in the L1-L2 intervertebral discs, the maximum stress of SG increased during left/right rotation compared with that of IG. Furthermore, the maximum displacement of SG was smaller than that of IG in the L1 vertebral bodies under all loading conditions.

CONCLUSIONS: SG can reduce the maximum stress in the vertebra and intervertebral discs, offering better biomechanical performance and improved stability than IG.