[Ultrasound fracture diagnosis--an experimental study]

Thanks to the increasing use of ultrasonography in the diagnostic evaluation of the musculoskeletal system, and the development of high-resolution ultrasonic transducers with ever better image quality, as well as the greater general trend towards non-invasive techniques, the use of ultrasonography in the diagnosis and follow-up of fractures would appear to make good sense. The aim of the present experimental study was, therefore, to identify the typical acoustic pattern of fractures and areas of bone impression and defects, while taking account of possible sources of error due to artefacts. Experiments were carried out on cadaver bones immersed in a water bath, using 7.5 and 10 MHz linear transducers. Depending on its size, the bony defect is represented by an interruption of the cortical echo, or a dorsal band of echoes limited to the fracture zone. Of interest is the fact that fractures and bony defects are not represented as such when the transducer is directed parallel to the line of the fracture or the impression area. Particular attention needs to be paid to the numerous artefacts occurring at the margins of the fracture. In summary, it may be noted that using resolution transducers under standardised experimental examination conditions, cortical interruptions of not less than 1 mm can be identified.