Objective. To identify the spectrum of possible pathogens and antibodies to them in the biological fluids and hip joint structures of adult patients with osteonecrosis of the femoral head.

Materials and methods. Laboratory examinations of 90 patients with osteonecrosis of the femoral head were carried out. The blood serum, synovial fluid, synovial membrane, articular cartilage of the femoral head were studied using enzyme-linked immunoassay, polymerase chain reaction, electron microscopy.

Results. Of 90 cases with non-traumatic femoral head necrosis, in 26 (28.9%) adults bacterial-viral antigens and antibodies to them were detected. Markers of herpesvirus (22.2%) and chlamydia (14.4%) infections were identified. The formulated algorithm allowed diagnosing femoral head osteonecrosis early as well as differentiate with the other hip joint pathologies.

Conclusion. The molecular-biological identification of pathogens such as C. trachomatis, herpes simplex virus type 1 and 2, cytomegalovirus, Epstein-Bar virus in hip joints in conjunction with the development of a specific local immune response may indicate at a possible pathogens dissemination from the primary infection foci and their role in the pathological process.