一种新型植骨重建钛网的三维有限元研究

目的研究新型植骨重建钛网的生物力学特点及其避免术后沉陷的有效性。方法设计并研制了一种新型的植骨重建钛网，以现有钛网为研究对照，建立使用2种钛网的椎体次全切除植骨重建手术的三维有限元模型，施加载荷，模拟术后颈椎活动，分别在屈曲、侧屈及扭转3种工况下施加73．6N的预载荷，观察钛网、钢板以及相邻椎体终板的应力分布。结果在3种不同工况条件下，使用新型植骨重建钛网较使用现有钛网可使钢板承受应力减低1．48—3．95MPa（23．5％～41．3％），钛网承受应力增加0．61～1．13MPa（12．2％～22．2％），相邻椎体下终板承受应力降低0．41～1．43MPa（27．7％～44．9％），相邻椎体上终板承受应力降低0．91～1．42MPa（28．0％-38．6％）。结论颈前路椎体次全切除减压术中使用新型钛网进行植骨重建可一定程度上增加手术节段稳定性，降低术后钛网沉陷的可能性。

Three-dimensional finite elements study of a new titanium mesh cage for bone grafting

Objective To study the biomechanical features of a new type titanium mesh cage and its effectiveness in avoiding postoperative subsidence. Methods A new type titanium mesh cage was designed. Two three-dimensional finite element models of anterior cervical corpectomy and fusion with new type titanium mesh cage or current type titanium mesh cage were established. The models were tested under preliminary loading of 73.6 N to simulate cervical physical action including flexion, lateral bending and rotation. The stress distribution of titanium mesh cage, cervical plate and adjacent vertebral endplates were compared between 2 models. Results Under 3 preliminary loading, comparing with current type titanium mesh cage, the new type titanium mesh cage made the stress distribution of cervical plate decreased by 1.48-3.95 MPa (23.5%-41.3%), and the stress distribution of TMC increased by 0.61-1.13 MPa (12.2%-22.2%), and the stress distribution of the adjacent upper vertebral endplate decreased by 0.41-1.43 MPa (27.7%-44.9%), and the stress distribution of the adjacent below vertebral endplate decreased by 0.91-1.42 MPa (28.0%-38.6%). Conclusion Anterior cervical corpectomy and fusion with new type titanium mesh cage will be helpful for increasing the segment stability and decreasing the possibility of postoperative titanium mesh cage subsidence.