Up to 30% of the adult population suffers from impingement syndrome with severe pain. Detection of the disease in the early stages is difficult. Early diagnosis of the initial signs of degenerative changes in the subacromial space saves the patient from surgery and additional risk of postoperative complications. The aim of the study is to evaluate the informative value of radiation methods for diagnosing subacromial impingement syndrome based on the analysis of papers published by domestic and foreign authors, depending on etiopathogenetic factors and anatomical structure of the shoulder joint. Materials and methods. The authors analyzed Russian and foreign publications on anatomical, etiological, pathogenetic, clinical, diagnostic features of subacromial conflict syndrome from databases: e-library (https://www.elibrary.ru), Oxford Medicine Online (https://academic.oup.com /), PubMed (https://pubmed.ncbi.nlm.nih.gov/) and others. The applied research methods were analysis and synthesis, axiomatic method and abstraction. Results. The development of subacromial impingement syndrome was revealed to be due to the structural features of the shoulder joint, which differs from other joints in anatomical and functional complexity. At this, changes in the rotator cuff of the shoulder joint develop under the influence of various etiopathogenetic factors, which can be both external (a decrease in subacromial space, an increase in the volume of the coracoacromial arch, instability, overload of the shoulder joint) and internal (changes in vascularization, pathology of collagen fibers' microstructure, degeneration of the tendons in the rotator cuff, etc.) Currently there is no unified approach to the algorithm of radiation diagnosing the early signs of impingement syndrome and injuries to the rotator cuff of the shoulder joint. Although radiography is a simple and informative method to assess the condition of the shoulder joint, its sensitivity at an early stage of impingement syndrome is insufficient. Magnetic resonance imaging is highly informative and sensitive in the diagnosis of injuries to the rotator cuff of the shoulder joint, however, it has a number of limitations, such as the presence of some contraindications, its high cost, protracted examination time, etc. Ultrasound examination is currently considered the preferred method in the diagnosis of impingement syndrome due to its high informative value, speed of execution and the possibility of its repeatability. Conclusions. The analysis of the informative value of radiation diagnostics methods showed that in identifying the early signs of subacromial impingement syndrome, taking into account etiopathogenetic factors and the anatomical structure of the shoulder joint, the ultrasound method is optimal and preferable; for more complex and controversial cases, according to certain indications, they are the methods of X-ray computer and magnetic resonance imaging. In the absence of the possibility of using high-tech diagnostic methods, classical radiography of the shoulder joint is performed.
