Biomechanical Study Of Sliding Load Unilateral Tridimensional External Fixator For The Treatment Of Inter-trochanteric Fracture

Objective Research has been Applied by biomechanical experiment for evaluate biomechanical properties of the sliding load unilateral tridimensional external fixator(SLUTEF),which can fixation inter-trochanteric fractur.Methods Fifteen adult femur specimens which have been fixed by formaldehyde were prepared. and the model of 31-A1.1 (AO classification) fracture was established. for the experimental group the specimens were fixed with the sliding load unilateral tridimensional external fixator (5 case) The control group were respectively applied with dynamic hip screw(DHS)(5 cases)and unilateral angulated external fixator(UAEF)(5 cases). Experimental tests were divided into the stress distribution in the broken ends of fracture, considerable contact area in the broken ends of fracture and maximum endurance and so on.Resultsâ‘ The experimental group and dynamic hip screw group including tension side were all pressure stress,but the traditional one arm external fixator were pulled stress except one point which called femoral calcar. We could see the stress distribution of experimental group and dynamic hip screw group arould the sliding screw in a limetted range.but the traditional one arm external fixator group only at femoral calcar piont.so the unilateral angulated external fixator lead to coxa vara easier than the experimental group and dynamic hip screw group.â‘¡The considerable contact area in the broken ends of fracture and the maximum endurance of the experimental group are superior to dynamic hip screw and the traditional one arm external fixator(P<0.05).Conclusion The considerable contact area in the broken ends of fracture and the maximum endurance of the experimental group are superior to dynamic hip screw and the unilateral angulated external fixator. that could make the fracture stable avoid or decrease coxa vara .