Measurement of bone morphogentic protein 7 level in serum and synovial fluid from patients with osteoarthritis and its clinical significance

Objective To study the possibility to use bone morphogenetic protein-7 (BMP-7) as a potential biomarker in early diagnosis of osteoarthritis (OA). Methods Plasma and synovial fluid (SF) samples were taken from 67 OA patients and 23 non-OA patients (11 meniscus injury patients, 9 anterior cruciate ligament injury patients, 2 discoid meniscus patients, and 1 patellar subluxation patient, with no significant articular cartilage lesion). Findings on their images were classified according to the Kellgren-Lawrence radiographic grading criteria. The BMP-7 levels in serum and SF were measured by ELISA. Results The BMP-7 levels in serum and SF were significantly higher in OA patients than in non-OA patients (P< 0.001) and in serum than in SF (P< 0.001), and correlated with the severity of OA (r=0.788, r=0.766, P< 0.001). In addition, the BMP-7 levels in serum and SF were positively correlated with each other (r=0.817, P< 0.001). Conclusion BMP-7 can be used as a biomarker in early diagnosis of OA and its prognosis monitoring.