Urine exosome in femoral head necrosis Raw sequence reads. Homo sapiens

Osteonecrosis of femoral head (ONFH) is an orthopedics disease with high disability rate. It occurs in young people aged 30-50 years old with loss of working ability, which brought a heavy burden to families and society . If there is no timely therapeutic intervention, 80% of ONFH will go to the late stage of osteonecrosis, and eventually accept total hip replacement. Therefore, early detection of ONFH with noninvasive means could postpone or even avoid joint replacement, which is an urgent problem in clinical practice. As the main RNA in exosomes, microRNA can avoid RNA degradation in the protection of bi-lipid membrane and keep its biological activity. More importantly, the number and composition of microRNAs in exosome are distinctly different between physiological state and pathological state, which facilitate the exosomal microRNA to be a noninvasive biomarker for early disease diagnosis. At present, the effect of exosomal microRNA on the diagnosis of steroid-induced osteonecrosis of femoral head (SINFH) remains elusive.