Ultrasound elastography: compression elastography and shear-wave elastography in the assessment of tendon injury

Abstract

Ultrasound elastography (USE) is a recent technology that has experienced major developments in the past two decades. The assessment of the main mechanical properties of tissues can be made with this technology by characterisation of their response to stress. This article reviews the two major techniques used in musculoskeletal elastography, compression elastography (CE) and shear-wave elastography (SWE), and evaluates the studies published on major electronic databases that use both techniques in the context of tendon pathology. CE accounts for more studies than SWE. The mechanical properties of tendons, particularly their stiffness, may be altered in the presence of tendon injury. CE and SWE have already been used for the assessment of Achilles tendons, patellar tendon, quadriceps tendon, epicondylar tendons and rotator cuff tendons and muscles. Achilles tendinopathy is the most studied tendon injury with USE, including the postoperative period after surgical repair of Achilles rupture tendon. In relation to conventional ultrasound (US), USE potentially increases the sensitivity and diagnostic accuracy in tendinopathy, and can detect pathological changes before they are visible in conventional US imaging. Several technical limitations are recognised, and standardisation is necessary to ensure repeatability and comparability of the results when using these techniques. Still, USE is a promising technique under development and may be used not only to promote an early diagnosis, but also to identify the risk of injury and to support the evaluation of rehabilitation interventions.Key Points• USE is used for the assessment of the mechanical properties of tissues, including the tendons.• USE increases diagnostic performance when coupled to conventional US imaging modalities.• USE will be useful in early diagnosis, tracking outcomes and monitoring treatments of tendon injury.• Technical issues and lack of standardisation limits USE use in the assessment of tendon injury.

Differences in Achilles tendon stiffness in people with gout.

“…The lack of agreed, validated SWE values for tendinopathy may currently limit its use in the assessment of tendon injury. [45] In line with previous work utilising both ultrasonography and dual energy CT, [25,[37][38][39] we have demonstrated a higher prevalence of both intra-tendinous tophi and intra-tendinous power Doppler signals in people with gout, yet limited structural damage per se. Laboratory-based studies have reported weaker foot/leg muscles in those with gout than non-gout participants.…”

Ultrasound Elastography in Musculoskeletal Radiology: Past, Present, and Future

“…[52][53][54] In Achilles tendinopathy evaluation, the studies showed moderate to perfect correlation between the USE and Bmode US and excellent correlation with functional scores. 54,55 Coombes et al reported that low shear wave velocity is correlated with higher age, self-reported pain, and with decreased loading capacity of the Achilles tendon. 56 Slane et al also showed lowering shear wave speed in older adults and reported that aging alters spatial variations in the Achilles tendon.…”

“…57 Studies in athletes demonstrated that tendon softening may predict pain and tendinopathy. 55 Thus USE may prove useful in the detection of subclinical tendinopathy, and timely preventive measures may be undertaken. 55 Subclinical changes of Achilles tendon were also shown with USE in patients with ankylosing spondylitis, acromegaly, and in patients with diabetic ulcers.…”

Differences in Achilles tendon stiffness in people with gout: a pilot study

“…However currently, the lack of agreed and validated SWE values for tendinopathy may limit its use in the formal assessment of tendon damage. [51] Previous clinical and laboratory-based studies have reported weaker foot/leg muscles in those with gout than in non-gout participants. [52,53] This muscle weakness was also associated with greater levels of foot pain.…”