Hip joint endoprosthesis with the Movshovich-Gavryushenko prosthesis having a reserve friction mechanism and a changeable cervical diaphysial angle

One of the main reasons for endoprosthesis instability (loosening) is a high friction coefficient in the mobility point. The tribological studies made at the Laboratory of Polymers, Central Institute of Traumatology and Orthopedics, have indicated that greasing the prosthesis mobility angle with bone marrow shows a 2-3-fold reduction in the friction coefficient. On this basis, a new type of the Movshovich-Gavryushenko hip joint endoprosthesis having a reserve friction mechanism was designed. In the prosthetic crus, neck, and head, a canal was formed, along which bone marrow drops entered the mobility node throughout the endoprosthetic functioning period. The endoprosthesis is also noted for its changeable cervical diaphysial angle due to the fact that there are three replaceable necks. This enables a surgeon to make the head have its varus or vagus position, as well as to place it in the ante- or retroversion position. Endoprosthesis by mean of the model was successfully performed in 146 patients, as shown by a 5-year follow-up.