Cerclage wiring technique after proximal femoral fracture in total hip arthroplasty

Cerclage wires have been used to stabilize proximal femoral cracks after st em insertion in cementless total hip arthroplasty. The objective of this st udy was to determine the optimal number and orientation of cerclage wires n ecessary to prevent stem subsidence and crack propagation. The crack was st abilized by 1, 2, or 3 wires placed either normal to the femoral neck axis or normal to the crack. The femora were compressed to 2,670 N while measuri ng crack opening and stem subsidence. Wires placed normal to the crack allo wed less stem subsidence by 3.17 mm and less crack opening by 1.55 mm compa red with wires placed normal to the neck. The addition of multiple wires re duced subsidence by 50% and reduced crack opening to <1 mm. Medial and ante rior calcar cracks are best stabilized by at least 2 cerclage wires that ar e placed normal to the crack.