The Biomechanical Comparative And Clinical Application Study For Three Kinds Of Internal Fixators For Femoral Intercondylar Fracture

1. The Biomechanical Comparative Study of three kinds of Internal Fixators For The Femoral Intercondylar FractureObjective : To study the biomechanics function of different internal fixations of distal femur fracture and to provide the scientics basis of the valid fixing methods for clinical c hoice .Methods : The 12 fresh specimen of distal femur were made into the necessar fracture models , which were fixed with the following fixation devices : condylar butress plate (CBP), dynamic condylar screw (DCS) and less invasive stabilization system (LISS).. Then the different internal fixation methods were tested and proved by means of experiment press analysis.Results : The experiment press analysis proved that the biomechanics function of LISS was better than that of CBP and DCS in the following aspects : load-strain, load-displacement ,load-axial rigidity ,load-shear rigidity and torsion moment-torsion angle .Conclusion : It is a good way of less invasive stabilization system (LISS) to treat th e femoral intracondylar fractures , which has the advantages of solid fixation and good b iomechanics function .And the clinical practice tests its reality .2. The clinical appliecation study of three kinds of internal fixations for femoral fractu re.Objective : To evaluate the effect of the three different internal fixations for the intracondylar femur fracture . Methods : From 2002 to 2008, 108 patients with femoral fractures were treated operatively , and condylar buttress plate (CBP) , dynamic condylar screw (DCS) and less invasive stabilization system (LISS) were used . 39patients with C type of distal femure fractures treated by internal fixation with LISS which involved 23male and 16 females with the average age 48.2 .According to AO fracture classification :C1 type in 16cases and C2 type in 13 cases and C3 type in 10 cases. 33patients with C type of distal femure fractures treated by internal fixation with DCS which involved 20 male and 13 females with the average age 46.2.According to AO fracture classification :C1 type in 18cases and C2 type in 11cases and C3 type in 4 cases. 36 patients with C type of distal femure fractures treated by internal fixation with CBP which involved 26male and 10 females with the average age 45.7 . 15cases and C2 type in 13cases and C3 type in 8 cases.According to AO fracture classification :C1 type in15 cases and C2 type in13 cases and C3 type in 8 cases.There was no statistical difference about clinical datas among three groops.Qualiative data were processed with X2 test and quantitative data with ANOVA test.Results :1,External fixation: For C1 type of facture,the rate of using external fixation of LISS ,DCS,CBPwas 0%,16.7% and 33.3%. There was statistical difference(P<0.05). There was no statistical difference(P>0.05)between DCS and CBP. For C2,C3 type of facture,the rate of using external fixation of LISS ,DCS,CBPwas 13.0%,66.7% and 71.4%. There was statistical difference(P<0.05). There was no statistical difference(P>0.05)between DCS and CBP.2,Knee function : For C1 type of facture,the good to excellent rate using LISS ,DCS,CBP was 100%,88.9% and 73.7%. There was statistical difference(P<0.05). For C2,C3 type of facture,the good to excellent rate using LISS ,DCS,CBP was 95.7%,66.7% and 61.9%. There was statistical difference(P<0.05). There was no statistical difference(P>0.05)between DCS and CBP.3,Complication: For C1 type of facture ,the rate of complication using LISS ,DCS,CBP was 0%,11.1%,11.1%. There was statistical difference(P<0.05). There was no statistical difference(P>0.05)between DCS and CBP. For C2,C3 type of facture, the rate of complication using LISS ,DCS,CBP was 4.3%,33.3%,47.6%. There was statistical difference(P<0.05). There was no statistical difference(P>0.05)between DCS and CBP.Conclusion :(1) DCS is mainly used For C1 type of femoral intracondylar factureand also can be used for supraccondylar othepedic operation. .It has some omplications when treating C1 type of femoral intracondylar facture.(2) CBP mainly used For C1 type of femoral intracondylar facture.It has some omplications and more fixation failures when treating C2 and C3 type of femoral intracondylar facture.(3) LISS can be used for all type of femoral intracondylar facture,and was the best choice with its angle stability, best function recovery and less complications .