Figure 5
Effect of surgical technique on the stress distribution within the implants. For the situation of an extended bone defect (Paprosky type IIb) we further explored the effect of surgical technique (implantation) on the implant stresses by varying femoral anteversion and examining its effect on the maximum principle (i.e. tensile) implant stresses. Here, the implant stresses of the standard (34 mm) and increased offset (44 mm) prostheses implanted at 14° of femoral anteversion are compared. This data is again presented as a histogram in image A (top), with the results reported as a percentage of the total number of elements in the implant stressed within a certain stress level. Below, image B compares the stress distributions along the lateral aspect of the implant for a type IIIb defect for the two different offsets. It can be seen that also for 14° of femoral anteversion the implant with the increased offset experiences larger tensile stresses than the standard prosthesis.