Effect of Interosseous Membrane on Load Transfer in Rat Forelimb Using Finite Element Analysis

Due to the curvature of the ulna and the complex geometry of the ulna and radius as well and their interaction with and possible transfer of load through the interosseous membrane that joins them, an understanding of the loading situation is not trivial. The IOM might counteract the bending effect resulting from the curvature of the ulna, therefore stabilizing the lateral displacement of the ulna and decreasing the ratio between bending and compression. Thus, in order to understand the mechanisms underlying effects of the mechanical stimulation applied using the end-loading model of the ulna, it is necessary to have a fundamental understanding of the loading mechanics and strain distribution. Hence, the goals of this study were: i) to develop a three dimensional finite element mesh of a mature rat ulna, ii) to measure experimental surface strain values of rat forelimbs with intact and non-intact interosseous membranes, iii) to compare experimental and computational strain distribution data, and iv) to analyze for the first time the effect of the radius and interosseous membrane on axial load distribution through the ulna.