Scope and limitations of ultrasonography in the documentation of fractures--an experimental study.

Sonographic studies were performed on cadaveric bones placed in a water bath, using 7.5-MHz linear-array transducers and 3.5-MHz sector transducers. Depending on its size, the defect was revealed as an interruption of the cortical reflection of echo or a dorsal band of echoes confined to the region of the fracture. It was interesting to note that fractures and bony defects are not visualized when the transducer is placed parallel to the fracture line or the zone of bony impaction. A further remarkable aspect was the numerous artefacts adjacent to each other at several fracture margins. It may be concluded that in an experimental setting and under standardized conditions, high-resolution transducers permit the examiner to detect cortical discontinuities of 1 mm or more.