Blatter G, Weber B G
Department of Orthopedic Surgery, Kantonsspital, St. Gallen, Switzerland.
Arch Orthop Trauma Surg. 1990;109(6):330-3. doi: 10.1007/BF00636171.
The load axis of the curved proximal femur lies not inside but outside the bone. Therefore, high bending forces are acting, the medial cortex absorbing pressure and the lateral cortex absorbs tension. In a transverse fracture, a laterally applied plate will absorb the tensile stresses and the medial cortex, the pressure forces. When the medial buttress due to a bony defect is missing, the laterally applied plate is subjected to cyclic bending and will undergo fatigue fracture. This dilemma is compensated by a wave plate with bone graft: the compression forces are redirected to the lateral cortex, and the plate is again subjected to tension. Furthermore, since the plate stands away from the bone, it does not disturb the blood supply at the fracture site and thus bone healing.