Adaptive bone remodeling around bonded noncemented total hip arthroplasty: A comparison between animal experiments and computer simulation

Severe loss of bone related to stress‐shielding is one problem threatening the long‐term integrity of noncemented total hip arthroplasty. It is widely accepted that this phenomenon is caused by adaptive bone remodeling according to Wolff's law. Recently, quantitative bone‐remodeling theories have been proposed, suitable for use in computer‐simulation models in combination with finite‐element codes, which can be applied to simulate the long‐term effect of the remodeling process. In the present paper, the results of such a computer simulation are compared with those in an animal experiment. A three‐dimensional finite‐element model was constructed from an animal experimental configuration concerning the implantation of a fully coated femoral hip prosthesis in dogs. The simulation results of the adaptive bone‐remodeling process (geometric adaptations at the periosteal surface and density adaptations within the cancellous bone) were compared with cross‐sectional measurements of the canine femurs after 2 years of follow‐up. The detailed comparison showed that long‐term changes in the morphology of bone around femoral components of total hip replacements can be fully explained with the present quantitative adaptive bone‐remodeling theory.