Use of electronic speckle pattern interferometry to study the biomechanics of human bone and prostheses

摘要

Electronic speckle pattern interferometry (ESPI) is a laser based technique developed for the study of stresses and strains in complex structures. This method consists of the projection of two laser beams onto the object of study. This produces a visible pattern that is recorded by a video camera. When the structure is stressed in a jig, the pattern changes depending on the in- plane and out-of-plane deformation and movement of the surface observed. This allows us to qualify and quantify strain in the whole area under study, in real time. We describe the method of application of ESPI to the study of the biomechanics of the proximal femur, before and after the implantation of the femoral component of a total hip replacement in cadaveric femora, under physiological loads and tensions, and report our preliminary results. The information obtained with this technique should provide a better understanding of the biomechanics of bone after joint replacement.