Ultrasound elastography for imaging tendons and muscles

Ultrasound elastography is a recently developed ultrasound-based method which allows the qualitative or quantitative evaluation of the mechanical properties of tissue. Strain (compression) ultrasound elastography is the commonest technique performed by applying mild compression with the hand-held transducer to create real-time strain distribution maps, which are color-coded and superimposed on the B-mode images. There is increasing evidence that ultrasound elastography can be used in the investigation of muscle, tendon and soft tissue disease in the clinical practice, as a supplementary tool to conventional ultrasound examination. Based on preliminary data, potential clinical applications include early diagnosis, staging, and guiding interventions musculotendinous and neuromuscular disease as well as monitoring disease during rehabilitation. Ultrasound elastography could also be used for research into the biomechanics and pathophysiology of musculotendinous disease. Despite the great interest in the technique, there is still limited evidence in the literature and there are several technical issues which limit the reproducibility of the method, including differences in quantification methods, artefacts, limitations and variation in the application of the technique by different users. This review presents the published evidence on musculoskeletal applications of strain elastography, discusses the technical issues and future perspectives of this method and emphasizes the need for standardization and further research.