[Load capacity and deformation of unstable pertrochanteric osteotomies following 145 degree angle plate osteosynthesis and Ender nailing].

In 24 femora an unstable intertrochanteric osteotomy was performed. In twelve an endernail osteosynthesis and in the other twelve a 145 degree-plate osteosynthesis was performed. Eight femora were tested as control. The loading capacity was 500 N higher in the endernail group. In four cases after 145 degrees-plate osteosynthesis but only in one case after endernailing the osteosynthesis becomes unstable under an alternating load of 2000 N. In femora with pronounced osteoporosis the maximal loading capacity is higher in the endernail osteosynthesis group. The loading capacity increase with the CCD-angle. The deformation after alternating load of 500 N is significantly lower in the 145 degree-plate osteosynthesis group. At higher alternating load the deformation of the 145 degree-plate osteosynthesis exceeds that of the endernail osteosynthesis.