Indications for the use of cerclage wires are long oblique or spiral fractures, in which at least two wires can be applied. They are usually used in conjunction with fractures repaired primarily with intramedullary pin placement. Cerclage wires can protect bone fissures, be used as a temporary fragment stabilizer but never as the only apparatus for a fracture repair.
The distance between the cerclage wires needs to be at least 1/2 bone diameter away from the tip of the fragment and ½-1 bone diameter away from each other.
In general, this is 0.5 cm from the tip of a fragment and 1 cm between each wire.
Pitfall: Placing cerclage wires on a short oblique fracture will generate larger shear forces, causing loss of reduction, the fracture to shear, and collapse.
The cerclage wire is placed around the bone using a wire passer. Avoid any soft-tissue entrapment between the bone and the wire.
Twist knot, single loop or double loop cerclage wire can be used. Double loop knots have the greatest knot tightness followed by single loop and then twist knot. If used underneath a bone plate, place the knot on the bone in a position that avoids interference with the plate.