A comparative analysis of the effects of two augmenters on the sensitivity of vertebral biomechanical behavior in vertebroplasty

The treatment of osteoporotic vertebral compression fractures (OVCFS) by transvertebral bone graft and augmentation (TBGA) has achieved satisfactory clinical results, but its biomechanical effects are not clear. The purpose of this study was to investigate the biomechanical effects of TBGA and compare the biomechanical sensitivity of the augmenter used in TBGA — a cylindrical enhancement device (CED) with bone cement. The finite element (FE) model of healthy segments T11-L3 (M1) was built, and two other models with L1 augmentation (M2, M3) were established to simulate CED and bone cement treatment, respectively. The stress and displacement distribution of the three models under five physiological loads were calculated and analyzed by the FE method. Based on the results, the sensitivities of biomechanical parameters to the degree of osteoporosis (DO) and loads were analyzed by linear fitting method using dummy variables. With the increase of DO, the CED is superior to bone cement in preventing the fractures of the augmented vertebral and the adjacent vertebral under the set loading conditions. Simulating TBGA method, the model 2 with L1 reconstructed was closer to the normal T11-L3 model in terms of sensitivity of stress and displacement under different loading conditions