[Using robots in hip prosthesis implantation. Precision with the wrong concept?].

Robot-assisted milling permits more precise preparation of the proximal femur, without necessarily optimizing stem placement. Currently propagated implantation concepts involving maximized implant-cortical bone contact may result in major biomechanical disadvantages, such as unphysiological load transfer in the proximal femur and increased stiffening in this region and subsequent stress shielding. While equipment procurement and running costs are higher, evidence of longer prosthetic life over the long-term has not been forthcoming. Against this background, present efforts to propagate this system for general use in hip replacement surgery cannot be justified.