Real-Time Sonoelastography: Findings in Patients with Symptomatic Achilles Tendons and Comparison to Healthy Volunteers

Purpose: Real-time sonoelastography (SE), a newly introduced ultrasound technique, has already shown conclusive results in breast, prostate, and thyroid tumor diagnostics. This study investigated the performance of SE for the differentiation of Achilles tendon alterations of tendinopathy compared to clinical examination and conventional ultrasound (US). Materials and Methods: Achilles tendons in 25 consecutive patients with chronic Achilles tendinopathy and 25 healthy volunteers were examined clinically by US and by SE. Results: In the healthy volunteers, SE showed the tendon to be hard (93%), while distinct softening was found in 57% of the patients. SE showed more frequent involvement of the distal (64%) and middle third (80%) than the proximal third (28%) of the Achilles tendon. Using SE a mean sensitivity of 94%, specificity of 99%, and accuracy of 97% were found when clinical examination was used as the reference standard. The correlation to US was 0.89. Mild softening was found in 7% of the healthy volunteers and in 11% of the patients. Conclusion: Our results emphasize that only distinct softening of Achilles tendons is comparable to clinical examination and US findings. However, mild softening might be explained by very early changes in tissue elasticity in the case of Achilles tendinopathy, which should be assessed in follow-up studies.