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Introduction The problem a large number of revision operations due to aseptic loosening after primary hip arthroplasty necessitates the search for a new material for a friction pair. The pyrocarbon, which has high tribological characteristics, can be used both in a monolithic and in a prefabricated design; however, the manufacture of a monolithic pyrocarbon block complicates production. Aim Compare the strength characteristics of the stem head and liner designs with monolithic and non-monolithic pyrocarbon. Materials and methods To assess the reliability of the designs, a digital mathematical model of the head and liner implants with a monolithic and non-monolithic pyrocarbon component was built. After the manufacture of prototypes friction pairs, an assessment of the static load on bench tests was carried out. Results While analyzing the mathematical model, the construct of non‑monolithic pyrocarbon broke in one of the experiments, while the strength of the construct of monolithic pyrocarbon was 4.5 times higher than the stresses arising under load. While studying the maximum static load, the friction pair from monolithic pyrocarbon exceeded the maximum possible load in the human hip joint by 5 times. Discussion The studies allow us to be confident about the reliability of the design in in vitro studies, which will create conditions for reducing the number of revision surgeries after hip arthroplasty. Conclusion Based on the data obtained, the design of the head and liner of the hip joint endoprosthesis with a friction pair made of carbon material will provide high reliability under conditions of functioning in the hip joint at maximum loads. It serves as a prerequisite for conducting a clinical study of the proposed friction pair.

Background. Osseointegration of medical equipment, including implants, into the bone is one of the main conditions for a successful outcome of surgical treatment. To improve the reliability of the functioning of medical equipment products by improving the osseointegrative properties, the authors have developed a unique technology for developing the surface of the implanted component. Thus, the aim of the work is to develop a technology for developing the surface of medical equipment products based on laser metal foaming. Materials and methods. Experimental studies have shown that the surface geometry and structure of the surface layer after laser foaming meet the requirements for medical equipment products for better osseointegration into the patient's bone. The results were confirmed by optical and electron microscopy data. Results. Studies have shown that the composition of the gaseous medium has the most significant effect on the structure of the surface layer. This factor determines the appearance in the surface layer of a large number of chemical compounds that significantly change the properties of the material. During the experiment, this factor was varied, and the rest were stabilized at a constant level. It has been established that the increase in the chemical inhomogeneity of the surface layer increases significantly with the introduction of air into the composition. When Argon is used as a working medium, the surface structure is normalized to the level of the material base. Conclusions. In the process of work, a developed structure was created on the selected surface area without changing the chemical composition with an increase in the area of osseointegrated structures up to 100 % of the original surface. For processing, it is recommended to use an inert gas medium, and the medium pressure must be above 8 bar. The feed speed of the laser head should be at least 5000 mm/min, but not exceed 10 000 mm/min.