Experimental substantiation of the etiopathogenetic approach in surgery of periarticular tissue pathology

The article presents the results of an experimental study of the strength of the structures of periarticular tissues on the example of cadaveric material of the bone-tendon complex of the distal biceps tendon and radius. The study was conducted on cadaveric material taken from men aged 35-45 years, no later than 48 days from the date of death, who, according to medical documentation, do not have pathology of the musculoskeletal system and systemic diseases that affect the strength of the studied tissues. 30 preparations of the distal biceps tendon and 30 preparations of the bone-tendon complex were standardized for testing. In the study used a servo-hydraulic multipurpose dynamic testing machine (for biomedical materials). The equipment corresponded to the possibility of conducting complex two-axis tensile/compression and rotation tests with control synchronization on both loading axes. The aim of the study was to study the structures of periarticular tissues most susceptible to damage, as well as to compare their characteristics in an experimental study. The results of the study showed the regularity of the primary damage to the transition site of the distal tendon of the biceps muscle of the shoulder into the tuberosity of the radius, which is a physiological transitional structure - fibrous-cartilaginous enthesis. At the critical point of application of force, stretching of the bone-tendon complex leads to the separation of the enthesal part, while maintaining the integrity of the fascia. When examining a tendon for stretching, first of all, there is a rupture of the fascial tissue covering the tendon, and only then the tendon fibers. The performed experimental study allows us to assert the important role of the physiological properties of the fascial-muscular structure in the complex of paraarticular tissues, such as elasticity, elasticity, contractility, performing a damping function in the ligament of the bone-tendon complex and playing an important role in preventing damage to periarticular tissues, in particular entheses, under the influence of mechanical factors.