骨折内固定松动与运动方式关系的生物力学评价

Biomechanical evaluation of the relation between internal fixation loosening and mode of exercise

目的:用生物力学的方法比较在不同运动方式下股骨中段骨折内固定疲劳前后稳定性,评价内固定松动与运动方式的关系。方法:取6根新鲜尸体股骨,制成股骨中段缺损骨折模型,对标本先后行单皮质钢板内固定和双皮质钢板内固定,并行疲劳实验,分别对6种运动方式即时和疲劳后的稳定性进行生物力学研究。结果:在同等载荷条件下,行前屈后伸运动时两种内固定方法的疲劳前后运动角度均有显著性差异(P<0.05),而在侧弯和旋转运动时疲劳前后无显著性差异(P>0.05)。结论:内固定螺钉的早期松动首先是对屈伸运动方向造成影响,引起屈伸方向的失稳,对侧弯和旋转运动稳定性影响最小。

Objective： To evaluate the relationship between internal fixation loosening and mode of exercise through comparison the biomechanical features of the internal fixation of femoral fracture. Methods： Six fresh femur of corpse were used and made into defect fracture model of midpiece femur. Mono-cortical and dipl-cortical bone plate internal fixation was done one after another and then a fatigue-test was performed. We studied the biomechanical stability of real time and post-fatigue. Results： At the same load, there was significant difference between ROM of real time and post-fatigue at flexion-extension in mono-cortical and dipl-cortical bone plate internal fixation （P〈0.05）, but the difference was not significant at bending and rotation （P〉0.05）. Conclusions： Early loosening of internal fixation firstly affect the flexion and extension, cause destabilization of flexion-extension direction, but tinily affect the stability of bending and rotation.