STRUCTURAL INTEGRITY OF IMPLANTED WMT INFINITY HIP AND OSTEONICS OMNIFIT HIP IN FRESH CADAVERIC FEMURS

Five matched pairs of fresh human femurs were used to quantitatively a ssess the structural integrity of the implanted Wright Medical Technol ogy modular Infinity hip and the Osteonics single piece Omnifit hip. T he results showed that neither bode implant system was able to recreat e the femoral anteversion of the intact femur (p < 0.05). Although the micromotion at the bone-implant interface was well within the limits of achieving bone ingrowth, the axial micromotion was greater for the Infinity hip than for the Omnifit hip (p < 0.05), but the rotational m icromotion did not show a significant difference between the two bone implant systems (p > 0.5). The anterior proximal femur deformation pat terns were similar for both the two bone implant systems and intact fe murs. However, the medial proximal femur deformation patterns showed t hat the infinity hip-implanted femur was more similar to the intact fe mur than the Osteonics Omnifit hip-implanted femur. (C) 1998 John Wile y & Sons, Inc.