ESOP is a range of cementless femoral stems that are anatomical and modular, available in 10 sizes of metaphysis for each side as well as a range of 7 diaphyses. This wide range of implants thus allows surgeons to propose, during the peri-operative period, a combination of 70 possibilities for each side. This principle of adapting the prosthesis to the morphology of the patient’s femur, rather than the opposite, is called “morphoadaptation”. After validating the excellent results obtained with this prosthesis, and after almost 20 years of clinical follow-up, we have modified this prosthesis so as to adapt it to LIS (Less Invasive Surgery), with a range of 3 diaphyseal pegs, thus increasing the morphoadaptation to 80 possibilities for each side. The set of instruments provided with this femoral prosthesis is simple, precise and satisfies the various requirements in terms of LIS approach, be it anterior, posterior, anteroexternal…