Wave plate osteosynthesis as a salvage procedure.

The load axis of the curved-shaped proximal femur lies not inside, but outside the bone. Therefore high bending forces are acting, the medial cortex absorbing pressure, the lateral cortex absorbing tension. In a transverse fracture, a laterally applied plate will absorb the tensile stresses, the medial cortex the pressure forces. When medial butress due to bony defect is missing, the laterally applied plate is subjected to cycling bending and will undergo fatigue fracture. This dilemma is compensated by a wave-plate with bone graft: The compression forces are detoured to the lateral cortex and the plate is again subjected to tension. Furthermore since the plate is standing away from the bone, the plate does not disturb the blood supply at the fracture side and bone healing.