External callus development on ultrasound and its mechanical correlation.

The authors compare the variations in the ultrasonographic and radiographic images with the strain gage values in long bone fractures treated by external fixation. The three test parameters were applied during the entire healing process of 239 fractures. There is a direct correlation between ultrasonographic changes and the calcification of the periosteal callus; there is also a correlation between the morphologic development visible on ultrasound and the stage of the callus. The strain gage values recorded were consistent with these variations.