Medical instruments - sets of medical instruments for the installation of hip / knee joint endoprostheses (TBS / CS endoprostheses). A medical instrument allows the surgeon to provide absolutely accurate positioning of the elements of endoprosthesis TBS / CS. Special devices virtually eliminate the possibility of error, while respecting the operational installation technique, ensure optimal restoration of biomechanics. The design and the materials used provide ease of care and withstand repeated sanitization.