Knee Ligament Stiffness Across Ethnicities Before and After Osteoarthritis Treatment

Inclusion Criteria * Healthy volunteers: * Adults aged 20 years or older. * Able to understand the study procedures and provide written informed consent. * Able to ambulate independently without walking aids. * No pain in either knee during the previous 6 months. * Patients with symptomatic knee osteoarthritis: * Adults aged 20 years or older. * Able to understand the study procedures and provide written informed consent. * Pain in at least one knee during the previous year. * Knee pain, soreness, or stiffness documented within the previous month. * Radiographic knee osteoarthritis defined by at least one of the following: * Kellgren-Lawrence grade ≥2 on anteroposterior radiographs. * Kellgren-Lawrence grade ≥2 on skyline radiographs. * Superior or inferior patellar osteophytes or posterior tibial osteophytes on lateral radiographs. Exclusion Criteria * Healthy volunteers: * Previous knee surgery. * Rupture of any cruciate or collateral ligament. * Major knee or periarticular trauma. * Rheumatic or autoimmune disease. * Diagnosis of knee osteoarthritis within the previous 6 months. * Patients with symptomatic knee osteoarthritis: * Rheumatic or autoimmune disease. * Malignancy. * Previous major knee trauma or knee surgery. * Corticosteroid injection into the affected knee within the previous 3 months.