Two single strain gages and one strain gage rosette were used to measure in vivo strains at three circumferential locations in the femoral midshaft of an adult dog. Bending theory and a finite element method of torsional analysis was used to calculate the result axial load, bending moments, and torsional moment acting at the section. Assuming transverse isotropy and homogeneity, the midshaft stress distributions at a particular instant of time during the stance phase of the gait cycle were calculated. The altered stress distributions created by the application of a standard ASIF fracture plate to the bone were determined for plates attached to the anterior, antero-lateral and lateral aspects. In vivo experiments of plate applications to the antero-lateral aspect of the canine femur were performed. Tetracycline labeling of these animals suggest that a strong relationship exists between the altered stress field and the distribution of bone remodeling induced by plate application.