The analysis of human femurs and prostheses using electronic speckle pattern interferometry

The potential lifetime of hip replacements is reduced by aseptic loosening-an inadequate fixation of the implant. Increasing the life of the surgical procedure requires knowledge of the interaction between prosthesis and femur. The authors have used electronic speckle pattern interferometry (ESPI), a laser-based metrology technique developed for the analysis of displacements and strains, to develop an understanding of the biomechanics of the proximal femur whilst mounted in a compression test rig which also simulates muscle and tendon behaviour. Cadaveric femora were studied under physiological loads, before and after the implantation of the femoral component of a total hip replacement