Osteoarthritis (OA) is the most common degenerative disease of the joint. Despite many reports and numerous clinical trials, OA is not entirely understood, and there is no effective treatment available for this disease. To satisfy this unmet medical need, drug delivery systems (DDSs) containing disease-modifying OA drugs (DMOADs) for intra-articular (IA) administration are required to improve the health of OA patients. DDSs should provide controlled and/or sustained drug release, enabling long-term treatment with a reduced number of injections. This paper reviews the role and interaction among different tissues involved in OA and summarizes recent clinical trials and research on DDSs, focusing on small-molecule delivery. To achieve an ideal treatment, various key criteria have been identified to design and develop an IA DDS matching the clinical needs.

骨关节炎（OA）是最常见的关节退行性疾病。尽管有许多报道和大量的临床试验，但是OA尚未被完全理解，并且对于这种疾病没有有效的治疗方法。为了满足这种未满足的医疗需求，需要用于关节内（IA）给药的包含疾病减轻性OA药物（DMOAD）的药物输送系统（DDS），以改善OA患者的健康。DDS应该提供受控和/或持续的药物释放，从而能够以减少的注射次数进行长期治疗。本文回顾了涉及OA的不同组织之间的作用和相互作用，并总结了有关DDS的最新临床试验和研究，重点是小分子递送。为了达到理想的治疗效果，