One of the most frequently performed accesses in the practice of an orthopedic veterinarian is access to the proximal epiphysis of the tibia. Access to the proximal epiphysis of the tibia is necessary in many cases of treatment of pathologies of the musculoskeletal system in cats and dogs and can be used in such surgical pathologies. The aim of the study was to consider options for surgical access to the proximal epiphysis of the tibia to perform osteosynthesis of fractures according to the Salter–Harris type, and osteotomy leveling the slope of the tibial plateau (TPLO) with anatomical and topographic justification. The study was conducted in the Network of veterinary centers "Kotonai" and the Department of Animal Anatomy of the St. Petersburg State University of Veterinary Medicine. The object of the study was dogs of small and medium breeds in the number of twelve individuals. The average age of the patients ranged from 6 months to 12 years. The study involved 5 intact females and 7 intact males. The average weight at the time of the study ranged from 2.5 to 21.0 kg. In the process of collecting the life history of all patients, the presence of chronic diseases, allergies and infectious diseases is excluded. The initial examination of the animal included: collection of anamneses of life and illness, general clinical examination, thermometry, neuroorthopedic examination, auscultation of the heart and lungs, X-ray examination under sedation. General clinical examination, thermometry and auscultation of the heart and lungs did not reveal pathological changes in all cases. According to the results of the study, it was found that there were no severe postoperative complications requiring repeated treatment in the studied patients. With the observance of clear anatomical and topographic landmarks in the formation of accesses, a good understanding of the anatomy of the medial and cranial surfaces of the tibia, visualization in the wound during surgical interventions (osteosynthesis of SalterHarris fractures, TPLO osteotomy) in the area of the proximal epiphysis of the tibia is convenient and safe.

Service dogs in the Russian Federation play the most important role in the executive authorities, performing complex tasks in which these trained animals are indispensable to this day. The most common service dog breeds on the territory of the Russian Federation participating in search, patrol, search, special, escort and guard activities are the German Shepherd, Belgian Shepherd, Spaniel, Labrador. Dysplasia of the elbow joint and injury with high-energy injuries, often has only surgical methods of treatment in dogs, it is necessary to develop the safest, most effective surgical approaches to the elbow joint with anatomical and topographic justification. The study was conducted in the network of veterinary centers "Kotonai" in St. Petersburg. The object of the study was dogs of the Labrador breed in the amount of 10 individuals. Research methods: morphometry, computed tomography. As a result of the study, it was found that the humerus has the lowest growth potential in the first age group, however, it has the largest area of epiphyseal zones, which may affect the planning of surgical interventions in the area of the elbow joint, as well as in the treatment of epiphysiolysis of the humerus. Evaluation of ossification of the processes of the ulna by computed tomography in case of suspected dysplastic changes in the type of disease of the medial coronary process and non-fusion of the hooked process is possible at the age of 5.5 months in Labrador dogs. To obtain more accurate data on the comparative anatomy of the bones forming the elbow joint, the study of this topic should be continued, and to reduce measurement errors, studies should be conducted on groups according to the sex of the animal.

Currently, infectious polyarthritis in cats is a very urgent problem in veterinary medicine. Worldwide, one of the most common causes of cat euthanasia is polyarthritis of unexplained etiology, which is not amenable to empirical and symptomatic treatment. The difficulty in diagnosing polyarthritis in cats lies in the large number of infectious agents that can penetrate into joint tissues with blood and lymph flow, while not all regions of the world have a full-fledged diagnosis of these diseases. The second reason complicating the diagnosis of polyarthritis in cats is the absence of infectious agents in the synovial fluid during its examination by various methods such as PCR, bacteriological culture, and ELISA diagnostics. The aim of the study was to consider an open method of biopsy of intraarticular structures in cats with infectious polyarthritis and to identify the safest places of material selection for patients with anatomical and topographic justification. The study was conducted in the Network of veterinary centers "Kotonai" and at the Department of Animal Anatomy of the St. Petersburg State University of Veterinary Medicine. The object of the study was cats in the number of six individuals. The average age of the patients ranged from 3 months to 9 years. There were no severe postoperative complications requiring repeated treatment in the studied patients. The clinical result in these cases can be called positive, despite the presence of minor complications in the early postoperative period. The diagnosis in most patients was established on the basis of examination of biopsies of the articular capsule and articular cartilage. For the collection of material in cats with polyarthritis and altered anatomy in the joint area, the safest localization is craniolateral access to the wrist joint, caudolateral access to the hock joint and cranial access to the hock joint.