Relevance The first metatarsophalangeal joint (MPJ) has an important function in the biomechanics of human gait, especially in the toe and thrust phases, as the full range of motion at this joint provides the body with smooth horizontal acceleration. The flattening of the arches of the foot and, as a result, the overload of its anterior section occupy a leading place in the etiology of deforming osteoarthritis (Hallux rigidus). Hallux rigidus is a disease associated with degenerative changes in the articular cartilage of the first metatarsophalangeal joint. The relevance of the treatment of arthrosis of the first metatarsophalangeal joint is determined by the high incidence and functional significance of the joint. At the 3rd and 4th degrees of arthrosis, arthrodesis, resection arthroplasty and arthroplasty of the first metatarsophalangeal joint are used. To date, the most optimal methods of surgical treatment of severe arthrosis of the first metatarsophalangeal joint are arthroplasty and arthrodesis of the joint. These operations are preferred because they achieve good clinical and radiological results. Long-term follow-up studies are needed to confirm the current findings. Uncoupled endoprostheses are characterized by satisfactory mobility, the ability to withstand high loads, and ligament structures are preserved during their implantation. Of the existing types of non-bonded endoprostheses, zirconium ceramics has a number of advantages, such as: good ingrowth ability, no wear, no rejection reactions. The main advantages of this type of surgical treatment are: rapid pain relief, improved function and stability, individual adaptation of prostheses. Endoprosthetics is recommended for patients of working age with high functional demands. Thus, the development and implementation of new design solutions in clinical practice is relevant and promising. task in the surgical treatment of patients with deforming osteoarthritis of the first metatarsophalangeal joint. Purpose of the study: To develop and introduce into clinical practice a new method of surgical treatment of patients with deforming osteoarthrosis of the first metatarsophalangeal joint using an anatomically adapted endoprosthesis.