Achilles tendinopathy is a common tissue injury that affects both athletes and the general population with pain, swelling and impaired physical function during daily activities.
Crawford
While US has been a common tool to diagnose, it has not always provided the most clinical information, such as the ability to assess the tendon structure and stiffness. This is needed to know when a patient is ready to return to normal activity.
A developing use of shear wave elastography US, could help provide clinicians and patients with more information, according to Scott Crawford, PhD, assistant professor in the Departments of Kinesiology and Orthopedics & Rehabilitation at the University of Wisconsin Madison.
"Shear wave imaging can non-invasively quantify tendon elasticity," Dr. Crawford said. "The purpose of the study was to determine the characteristics of both traditional sonographic measures and regional shear wave speed, or SWS, between limbs in patients with Achilles tendinopathy."
Study Looked at Tendon Stiffness and Thickness
Participants were recruited from April 2014 to Nov. 2017 as part of a randomized trial among patients between 18 and 65 years of age who had experienced unilateral mid-substance Achilles tendon pain for more than six months. The patients had failed conservative treatments, had no steroid injection within the past six weeks and had no history of surgery or systemic disease.
Overall, 20 subjects were enrolled in the study. Researchers then used traditional sonographic measures of tendon structure as well as regional SWS collected in a resting ankle position, for both the symptomatic and non-symptomatic ankle.
Using shear wave imaging to estimate tendon stiffness, the team used lower SWS only in the free tendon and compared to the contralateral limb, indicating that alterations in tendon elasticity associated with Achilles tendinopathy were localized there and did not involve the proximal passive tendon structures of the nearby limbs.
The results also found that symptomatic tendons were thicker and had more hyperemia and hypoechogenicity, or decreased response during US exam, than the other tendon.
Further Investigation Needed
Dr. Crawford said that because the study was so small and did not have a control group of healthy individuals, further studies are needed.
"A reliable quantitative measure of tendon elasticity allows for clinical validation studies to address important topics such as return to activity and the effectiveness of rehabilitation protocols. Large clinical trials should consider including advanced technique such as SWS especially when evaluating emerging injection therapies like platelet-rich plasma or percutaneous tenotomy," Dr. Crawford said. "It's a really exciting proposition to see how we can use this work to inform practices and improve the overall quality of life for individuals struggling with chronic pain."
Access the presentation, "Regional Ultrasound Shear Wave Elastography of Mid-substance Achilles Tendinopathy: A Pilot Study Assessing Shear Wave Speeds in Symptomatic Achilles Tendons Compared to the Contralateral Achilles," (W3-SSMK08-1) on demand at Meeting.RSNA.org.
