Assessing the Tendons With Shear Wave Elastography

This study is assessing how well shear wave elastography — an ultrasound-based imaging technique — can measure the stiffness of tendons. Tendon injuries and conditions like tendinopathy (chronic tendon pain and degeneration) are very common in the general population and especially in athletes. Currently, tendon health is assessed mainly through MRI or standard ultrasound, but these methods have limitations. Shear wave elastography can measure tissue stiffness directly and may offer a more sensitive way to detect tendon changes before they become serious injuries. The study compares measurements in people with known tendon problems against healthy volunteers without tendon symptoms. The goal is to validate this imaging technique as a reliable clinical tool. You may be eligible if: - You are between 18 and 65 years old - You are presenting with lower extremity pain without tendon involvement (for the healthy/asymptomatic group) - OR you have a clinical diagnosis of tenalgia (tendon pain) confirmed by ultrasound (for the symptomatic group) You may NOT be eligible if: - You are pregnant - You have a history of tendinopathy, tendon surgery, or tendon morphological abnormalities - You have systemic, metabolic, or endocrine diseases, or psoriasis - You have been treated with corticosteroids, estrogens, long-term quinolone antibiotics, or cholesterol-lowering drugs Talk to your doctor to see if this trial is right for you.