The paper presents some aspects and practical solutions of synovial joints treatment for the patients with hip and knee osteoarthritis, realized at Recovery Clinical Hospital of Felix Spa, Oncology Clinical Hospital of Oradea and our university. A theoretical model of human body under applied and conjunction forces, explained the vibration damping and shocks into synovial joints from elastic modulus of bone cartilages in contact and variation of dynamic viscosity’s synovial fluid. The treatment was applied to the patients with osteoarthritis that consists in combination between conservative measures with radiological treatment, by using irradiation with gamma ray, due to improving bio-lubrication into cartilages of synovial joints with severe osteoarthritis in slow evolution. The treatment is following by a recovery process of patients such as hydro-kinetotherapy, massage, etc. In addition, a study about 260 subjects with osteoarthritis using balneal-physiotherapy at Recovery Clinical Hospital of Felix Spa is presented. These combination treatments have assured an amelioration of patients with osteoarthritis and due to improving the bio-lubrication between cartilages of synovial joints.