RESUMEN

Background: The rigidity in osteosynthesis causes primary healing, and it takes longer to heal. The flexibility provided to the fixation allows micromotion between fragments which accelerates secondary healing. Methods: In this study, the healing outcomes of nailing and plating in different fixation stabilities were investigated and compared by using a finite element tool. The clinical observational study was also performed to verify the results of the finite element analysis. The nonlinear contact analysis was performed on 5 different fixation configurations capturing nail and plate in immediate post-surgery. Results: The finite element analysis results showed that flexibility instead of rigidity in interlock nail implantation increases the axial and shear micromotion near the fracture site by 47.4% (P < 0.05) and 12.4% (P < 0.05), respectively. For LCDCP implantation, the flexible fixation increases the axial and shear micromotion near fracture site by 75.7% (P < 0.05) and 25.3% (P < 0.05), respectively. Conclusion: Our findings suggest that flexible fixations of interlock nail and LCDCP provide a preferred mechanical environment for healing, and hence, the LCDCP in flexible mode can be an effective alternative to interlock nail for the femur diaphyseal fracture. Supplementary Information: The online version contains supplementary material available at 10.1007/s43465-022-00795-1.