The Biomechanical Comparative And Clinical Applied Study For Different Internal Fixations Of The Distal Femur Fracture

1 The Biomechanical Comparative Study for Different Internal Fixations of The Distal Femur FractureObjective: To study the biomechanics function of different internal fixations of the distal femur fracture and to provide the scientics basis of the valid fixing methods for clinical choice.Methods: The 40 fresh specimen of distal femur were made into the necessary fracture models, which were fixed with the following fixation devices: retrograde locked intramedullary nail, condylar blade plate, 95 degree dynamic condylar screw and condylar buttress plate. Then the different internal fixation methods were tested and proved by means of experiment press analysis and limited dollar analysis.Results: The experiment press analysis proved that the force of anti-compress and anti-bend of retrograde locked intramedullary nail was better than that of condylar blade plate, 95 degree dynamic condylar screw and condylar buttress plate,and the force of anti-torsion of retrograde locked intramedullary nail and 95 degree dynamic condylar screw was better than that of condylar blade plate and condylar buttress plate, particularly 95 degree dynamic condylar screw was so.Conclusion: It is a good way of retrograde locked intramedullary nail and 95 degree dynamic condylar screw to treat the femoral supracondylar and intracondylar fractures, which has the advantages of solid fixation and good biomechanics function. And the clinical practice tests its reality.2 The Clinical Applied Study for Different Internal Fixations of The Distal Femur Fracture.Objective: To evaluate the effect of the four different internal fixations for The distal femur fracture.Methods: From 1997 to 2003, 118 patients with distal femoral fractures were treated operatively, and the retrograde locked intramedullary nail, condylar blade plate, 95 degree dynamic condylar screw and condylar buttress plate were used.Results: According to the Merchan's functional rating scale ,the functional scores of retrograde locked intramedullary nail groop: 9 excellent 17 good and 4 fair, with a good to excellenct rate of 86.6%; that of 95 degree dynamic condylar screw groop: 4 excellent 12 good and 3fair,with a good to excellenct rate of 83.7%; that of condylar buttress plate groop:3 excellent , 11 good and 4 fair, with a good to excellenct rate of 77.8%; that of condylar blade plate groop: 8 excellent, 30 good and 13 fair, with a good to excellenct rate of 74.4%.Conclusion: Retrograde locked intramedullary nail and 95 degree dynamic condylar screw for distal end of the femur is a good way that has the advantages of simple performance, solid fixation and adapting early rehabilitation exercise etc, which has been proven by the biomechanical comparative experiment.