Objective: The aim: Tо present enhanced (with the contrast) and non-enhanced MRI techniques, provide an update on the physical principles of the main and latest techniques, and describe the advantages and disadvantages of each technique. The information obtained can provide an opportunity to diagnose changes at the structural level of the articular cartilage, thereby improving the early diagnosis of OA and optimizing the tactics of further treatment of patients.

Patients and methods: Materials and methods: We retrospectively reviewed publications published in the PubMed and Embase databases up to February 2023 using the following terms: "MRI cartilage", "MRI osteochondral lesion", "T2 mapping cartilage", "dGEMRIC", "DWI cartilage", "DTI cartilage", "sodium MRI cartilage", "gagCEST", "T1rho cartilage". A manual search for review references was also carried out. Comparative, analytical, as well as the method of meaningful analysis was used.

Conclusion: Conclusions: Modern methods of MRI examination of the articular cartilage make it possible to assess its structure more accurately, in comparison with only a morphological assessment. In most cases, the components of the ECM, namely PG, GAG and collagen, are evaluated. Among the available methods, the most common, informative and accessible technique is T2 mapping. T1ρ and dGEMRIC are also fairly common methods, but require longer acquisition times. DWI/DTI, sodium MRI, gagCEST, and T1ρ are promising methods because they do not require the administration of a contrast agent and are quite specific for assessing PG and GAG. However, the available methods of MRI research already provide more detailed information about the state of the articular cartilage, which has a positive effect on the treatment of patients in this group.