Biomechanical Effects of Cement Volume on Treatment of Thoracolumbar Compression Fracture with Vertebroplasty
10.16156/j.1004-7220.2018.01.02
- VernacularTitle:骨水泥对椎体成形术治疗胸腰椎骨质疏松压缩性骨折的生物力学影响
- Author:
Jiaqiong LI
1
;
Dongmei WANG
1
;
Jingchuan SUN
2
;
Yong YANG
2
;
Jiangang SHI
2
Author Information
1. School of Mechanical Engineering, Shanghai Jiao Tong University
2. Department of Orthopedics，Shanghai Changzheng Hospital affiliated to the Second Military Medical University
- Publication Type:Journal Article
- Keywords:
vertebroplasty;
osteoporosis;
bone cement;
biomechanics;
finite element method
- From:
Journal of Medical Biomechanics
2018;33(1):E006-E012
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the biomechanical effect from different volumes of bone cement on osteoporotic spine T11-L3 at different levels of osteoporosis in vertebroplasty by the finite element method, so as to offer theoretical foundation for the selection of cement volume before vertebroplasty. Methods Based on CT scan images, the finite element models of spine T11-L3 were built and validated. Twelve models of osteoporotic spine T11-L3 without bone cement were developed as the control models. The spine L1 was injected with 1.8 mL and 3.6 mL bone cement, respectively, to strengthen the spine and build 24 models of spine T11-L3 at different levels of osteoporosis. The vertical load (500 N) and the torque (7 N·m) were applied on superior face of the spine T11 to calculate and analyze vertebral stress and displacement under the working conditions of standing, backward extension, anteflexion, lateral bending and rotation, respectively. Results After injection of bone cement, the changes in vertebral stress and displacement under torsional loads were the maximum. For the models with injection of 1.8 mL bone cement, as the levels of osteoporosis increased, the stress of spine L1 increased from 55.0% to 87.7%, and the displacement decreased from 6.5% to 32.0% under torsional loads. The torsional stress of spine T12 and L1 at the highest level of osteoporosis increased by 3.6% and 5.7%, respectively. For the models with injection of 1.8 mL bone cement, as the level of osteoporosis increased, the stress of spine L1 increased from 288.5% to 313.8%, and the displacement decreased from 8.9% to 44.7% under torsional loads. The torsional stress of spine T12 and L1 at the highest level of osteoporosis increased by 7.3% and 7.6%, respectively. Conclusions The deterioration in osteoporosis and the increase in cement volume will lead to the increase in vertebral stress. The vertebral stress and displacement will increase most under torsional loads. Therefore, for patients with vertebral fracture at high level of osteoporosis, low-dosage bone cement should be considered in order to avoid a large increase in stress, and torsional movement of the patients should be restricted.
