INFLUENCE OF FIXATION STABILIZATION ON FEMUR DIAPHYSEAL FRACTURE HEALING — A FINITE ELEMENT STUDY COMPARING HEALING OUTCOMES OF NAILING AND PLATING

Abstract

Primary healing is caused by rigid osteosynthesis and it takes longer to heal. The flexibility provided by fixation allows micromotion between fragments which allows secondary healing. In this study, the healing outcomes of nailing and plating in different fixation stability were investigated and compared by using the finite element tool. The nonlinear contact analysis was performed on 10 different fixation configurations capturing interlock nail and compression plate in post-surgery and post-healing (PH) phases. The post-surgery results showed that flexibility instead of rigidity in nail implantation increases the axial and shear micromotion near fracture site by 47.4% ([Formula: see text]) and 12.4% ([Formula: see text]), respectively. For plate implantation, the flexible fixation increases the axial and shear micromotion near the fracture site by 75.7% ([Formula: see text]) and 25.3% ([Formula: see text]), respectively. The PH results show that the highest rise in mean stress in bone when compared with intact bone was found to be 13.4% for nail and 202% for plate. Our findings suggest that flexible fixations of nail and plate with six screws discussed in this study provide a preferred mechanical environment for healing. These two configurations were also observed to reduce post-surgery complications.