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目的 分析新型骨-骨水泥-假体模型在增加环形凹槽后的生物力学和界面微观变化.方法 使用刀具对骨床进行处理,使之产生两个环形凹槽,建立新型骨-骨水泥-假体模型,将没有环形凹槽的模型作为对照组.将两种模型使用Micro-CT进行检测,计算模型的微观参数.然后将模型使用生物力学测试仪进行生物力学测试.对比分析实验组和对照组的骨-骨水泥界面接触面积和模型孔隙率,生物力学的测试结果 ,并对模型微观参数和生物力学测试结果进行相关性分析.结果实验组的骨-骨水泥界面的接触面积(5470±265)mm2明显大于对照组(5289±299)mm2,但是两组之间的孔隙率差异无统计学意义(1.50±0.382)％vs.(1.59±0.496)％.生物力学测试结果显示:模型的失效主要发生在骨-骨水泥界面.相对于对照组,实验组的抗拉伸(7337±1825)N vs.(5564±1359)N和抗旋转能力(65.70±4.83)N·m vs.(60.60±4.43)N·m明显大于对照组.其次,研究发现模型的抗拉伸和抗旋转能力与骨-骨水泥的接触面积有明显正相关性R2=0.85和R2=0.77,但是与模型的孔隙率成负相关R2=0.57和R2=0.43.有限元分析发现,实验组模型有更小的应力分布现象.结论 通过处理使骨质髓腔内壁产生环形凹槽,导致骨水泥和骨质可以更好地进行交锁,增强骨-骨水泥界面的强度,提高骨水泥型人工关节初始稳定性.“,”Objective To identify whether the strength of bone-cement interface could be increased by changing the morphology of inner wall of bone medullary canal with grooves. Methods Self-developed new reamer was used to process fresh pig reamed femoral canal, resulting in two cortical grooves in the canal wall of the experimental group. We used the Micro-CT to scan all the models, and observed the infiltration of cement and to determin the differencs between the new bone-cement interface and the traditional interface. We used the biomechanical testing instrument to test the new and traditional bone-cement-prosthesis model ( tensile testing and rotation testing ), until the model failed. The biomechanical strength of both models was compared. We analyzed the correlation between the results of microscopic detection and biomechanical testing. Results The contact area of the bone-cement interface was greater for the experimental group ( 5470 ± 265 ) mm2 when compared to the specimens of the control group ( 5289 ± 299 ) mm2. However, the porosity for the experimental group ( 1.50 ± 0.382 ) ％ was similar to that of the control group ( 1.59 ± 0.496 ) ％. In addition, biomechanical responses to tensile loading ( 7337 ± 1825 ) N vs. ( 5564 ± 1359 ) N and anti-rotation capability ( 65.70 ± 4.83 ) N · m vs. ( 60.60 ± 4.43 ) N · m showed that the specimens of the experimental group had stronger strains at the bone-cement interface compared to the control group. In the tensile testing, the contact area of bone-cement interface and the tensile force of models had strongly significant positive correlation ( R2 = 0.85 ). In the rotational testing, the contact area of bone-cement interface and the maximal torsion had a strong correlation ( R2 = 0.77 ). The relationships between the tensile force and the porosity and the maximal torsion and the porosity were observed. ( R2 = 0.57 and R2 = 0.43 ). The FEA results compared favorably to the tensile and torsion relationships determined experimentally. Conclusions Converting the standard reaming process from a smooth boring cortical tube to one with grooves permits the cement to interlock with the reamed bony wall. This would increase the strength of the bone-cement interface. We believe that the addition of such grooves has the potential to enhance cement fixation to the bone, provide better initial fixation and extend longevity of the bone-cement-implant composite.