关键词: 椎间盘退行性变, 终板形态, 生物力学现象

Abstract: Objective To investigate the biomechanical effects of different healing morphology of cartilage endplate on endplate itself and intervertebral disc. 
Methods A healthy adult male volunteer in the Third Hospital of Hebei Medical University underwent computed tomography scans from T12 to L2 vertebrae. The solid spine model was constructed after three-dimensional reconstruction. Four different cartilaginous endplate models including normal endplate, increased curvature endplate, irregular healing endplate and traumatic Schmorl node endplate were constructed. After validation of the model, 500 N vertical load was applied to the upper surface of the T12 vertebral body to obtain the stress distribution of cartilage endplate and intervertebral disc in each model. 
Results The stress of nucleus pulposus increased slightly in increased curvature model, and decreased significantly in irregular healing model and traumatic Schmorl node model by 38.1% and 27.5%, respectively. The stress of annulus fibrosus decreased slightly in increased curvature model, and increased significantly in irregular healing model and traumatic Schmorl node model by 9.8% and 6.3%, respectively. In addition, the stress concentration of the annulus fibrosus was relatively clear, which was located in the junction area with the nucleus pulposus and the periphery of the annulus fibrosus. 
Conclusion The morphological changes of cartilage endplate can lead to the redistribution of stress in the intervertebral disc, which provides a biomechanical evidence for the morphological changes of cartilage endplate leading to intervertebral disc degeneration. 

Key words: intervertebral disc degeneration, endplate morphology, biomechanical phenomena