QUANTIFICATION OF HOLOGRAPHIC FRINGE DATA - COMPARISON OF INTACT AND IMPLANTED FEMURS

The strains developed on the surface of a femur with and without an im planted femoral hip replacement were investigated using holographic in terferometry (HI). Interferometric fringe data from the four aspects o f the loaded femur were quantified and the resulting curvature calcula ted. Curvature was related to the strain along the long axis of the fe mur and the results for the intact and implanted femur compared. Chang es were found in femoral strain patterns resulting from the implantati on of both a cemented and an uncemented Norwich femoral component. All four aspects of the proximal 120 mm of the femur showed reduced strai n as a result of prosthesis implantation irrespective of the method of prosthesis fixation. The distal half of the femur showed no such chan ges, No statistical difference was found between the loading patterns in the proximal femur of the uncemented and the cemented prosthesis. ( C) 1998 IPEM. Published by Elsevier Science Ltd. All rights reserved.