Introduction: Osteoarthritis (OA) is a degenerative disease which primarily affects hyaline cartilage, leading to pain, stiffness and loss of mobility of the entire articulation. Diagnosis is commonly based on symptoms and radiographs, but there is a growing interest in detecting novel biomarkers, in serum, urine and synovial fluid, which can be predictors of disease onset and progression.

Areas covered: This review provides an overview of the main biomarkers currently used in OA clinical practice, with a focus on lubricin, a surface glycoprotein secreted in the synovial fluid that lubricates the cartilage and reduces the coefficient of friction within the joint. Key findings of the last years are presented throughout the article.

Expert opinion: Analysis of biomarkers might suggest personalized protocols of treatment, guide the classification of OA phenotypes, contribute to precision medicine, avoid further unnecessary exams, facilitate drug discovery or refine treatment guidelines. For all these reasons, the investigation of novel cartilage-based biomarker of osteoarthritis needs to be promoted and improved.

简介： 骨关节炎 (OA) 是一种退行性疾病，主要影响透明软骨，导致整个关节疼痛、僵硬和丧失活动能力。诊断通常基于症状和 X 光片，但人们越来越关注检测血清、尿液和滑液中的新型生物标志物，这些生物标志物可以预测疾病的发生和进展。

涵盖的领域：本综述概述了目前在 OA 临床实践中使用的主要生物标志物，重点是润滑素，一种分泌在滑液中的表面糖蛋白，可润滑软骨并降低关节内的摩擦系数。整篇文章都介绍了过去几年的主要发现。

专家意见：生物标志物分析可能会建议个性化的治疗方案，指导 OA 表型的分类，有助于精准医疗，避免进一步不必要的检查，促进药物发现或完善治疗指南。由于所有这些原因，需要促进和改进基于软骨的新型骨关节炎生物标志物的研究。