Spinal thoracolumbar vertebrae stability change and risk prediction of vertebral compression fracture in osteoporosis patients: a finite element analysis(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2021年第4期
- Page:
- 485-494
- Research Field:
- 生物材料与力学
- Publishing date:
Info
- Title:
- Spinal thoracolumbar vertebrae stability change and risk prediction of vertebral compression fracture in osteoporosis patients: a finite element analysis
- Author(s):
- QIN Daping1; 2; ZHANG Xiaogang2; QUAN Zhen1; ZHANG Hua1; CAO Linzhong1; CHEN Bo1; XU Bin1; XU Shiwei2
- 1. Clinical College of Traditional Chinese Medicine, Gansu University of Chinese Medicine, Lanzhou 730000, China 2. Department of Spine Surgery, Affiliated Hospital of Gansu University of Chinese Medicine, Lanzhou 730020, China
- Keywords:
- Keywords: osteoporosis mechanical stability prediction of thoracolumbar compression fracture risk finite element analysis
- PACS:
- R318
- DOI:
- DOI:10.3969/j.issn.1005-202X.2021.04.017
- Abstract:
- Abstract: Objective To apply finite element analysis for analyzing the changes of the mechanical stability of the thoracolumbar vertebrae in osteoporosis patients in different motion states, and then compare the established finite element model with the normal human model, and to predict the risk of compression fracture, thereby providing theoretical and biomechanical basis for the standardization of intervention strategy. Methods A male volunteer who didn’t had the history of spinal thoracolumbar vertebrae injuries were enrolled in the study. Moreover, the thoracolumbar CT and MRI scan data of 2 hospitalized elderly osteoporosis women were selected to establish a three-dimensional finite element model of the osteoporotic vertebral body T11-L2, and then the validity of the established model was verified. The biological forces in different motion states under normal physiological load was analyzed and the Von Mises stresses of vertebral body, articular process joint, endplate, fibrous ring, cancellous bone, intervertebral disc and nucleus pulposus, and the maximal displacement of vertebral body were compared between two groups and finally, the physiological and pathological joint stress changes were analyzed using stress cloud map. Results The analysis on the material properties, elastic modulus, stiffness, strength of normal human spine and thoracolumbar spine in osteoporosis patients and the changes of mechanical and biological environment showed that the Von Mises stresses of vertebral body structure including vertebral body, articular process joint, intervertebral disc, end plate, fibrous ring and nucleus pulposus in osteoporosis patients under 7 motion states (forward flexion, extension, left and right lateral bending, left and right rotation, axial motion) were decreased significantly and the maximum displacement of vertebral body showed an increasing trend. In addition, the study established an osteoporosis model using clinical CT data and patients who were diagnosed with osteoporosis confirmed by specific clinical symptoms and bone mineral density, instead of adopting the model with reduced elastic modulus of cortical bone, cancellous bone and endplate which was provided in literatures. Compared with the model provided in the current literatures, the model established in the study was more consistent with the biomechanical characteristics and attribute changes of the actual spinal thoracolumbar vertebral body and accessory structure in osteoporosis patients. The analysis on musculoskeletal system showed that compared with those of normal human model, the dynamic and dynamic changes represented by bone, muscle and ligament of the model established in the study were significantly decreased, which also confirmed the change of clinical real data. Conclusion The uneven stress distribution and the tendency of stress concentration in thoracolumbar vertebrae in osteoporosis patients lead to abnormal changes of stresses in thoracolumbar vertebrae, intervertebral disc, nucleus pulposus, fibrosis, articular process and surrounding accessory structures, namely the abnormal change of elastic modulus of bone and the decrease of binding force of surrounding accessory structures, which will result in imbalance of musculoskeletal system and decrease of long-term stability, thus increasing the degeneration and risk of thoracolumbar compression fracture. The study also provide theoretical and biomechanical basis for the standardization of intervention strategy for thoracolumbar compression fracture risk.
Last Update: 2021-04-29