Höger Svenja A, Cong Ting, Hall Arielle J, Lane Joseph, Runer Armin
Department of Sports Orthopeadics, TUM University Hospital, Munich, Germany.
UPMC Freddie Fu Sports Medicine Center, University of Pittsburgh Medical Center, Pittsburgh, PA, USA.
Ann Jt. 2025 Jul 9;10:27. doi: 10.21037/aoj-25-12. eCollection 2025.
Subchondral bone plays a critical yet often underappreciated role in osteochondral health, injury response, and the pathophysiology of osteoarthritis (OA). A limited understanding of subchondral bone behavior limits the accurate evaluation of cartilage repair outcomes. Alterations in the subchondral bone-such as changes in bone density and structure, subchondral cyst (SCC) formation, impairment of osseous microarchitecture, and overgrowth of the subchondral plate-can compromise the mechanical osteochondral unit's integrity, leading to compromised joint function and poor outcomes. Moreover, neuropathy and subchondral bone changes, both significant contributors to OA-related pain and progression, are rarely assessed in treatment strategies. A deeper understanding of subchondral bone dynamics could improve both the assessment of repair outcomes and the development of more effective therapeutic strategies for OA. In the context of cartilage procedures, clinical and translational studies revealed that up to one-third of patients undergoing microfracture or similar subchondral venting procedures exhibit clinically pathologic subchondral bone changes. These include cyst formation and upward migration of the bone plate, which negatively affect repair outcomes. Translational models further support these findings by elucidating the mechanisms of subchondral bone remodeling and its critical influence on cartilage health. This review focuses on recent translational research on the subchondral bone in both osteochondral health, injury, and OA, highlighting the need to preserve its integrity during cartilage repair and ensuring that subchondral bone is considered in OA therapy. Understanding subchondral bone alterations may guide repair strategies, including biologic therapies and biomaterial-based approaches aimed at restoring osteochondral function, paving the way for improved clinical outcomes.
软骨下骨在骨软骨健康、损伤反应及骨关节炎（OA）的病理生理学中起着关键但常被忽视的作用。对软骨下骨行为的有限理解限制了对软骨修复结果的准确评估。软骨下骨的改变，如骨密度和结构的变化、软骨下囊肿（SCC）形成、骨微结构受损以及软骨下板增生，会损害机械性骨软骨单元的完整性，导致关节功能受损和预后不良。此外，神经病变和软骨下骨改变都是OA相关疼痛和病情进展的重要因素，但在治疗策略中很少被评估。对软骨下骨动态变化的更深入理解可以改善对修复结果的评估，并为OA开发更有效的治疗策略。在软骨手术方面，临床和转化研究表明，接受微骨折或类似软骨下钻孔手术的患者中，高达三分之一表现出临床病理性软骨下骨改变。这些改变包括囊肿形成和骨板向上移位，对修复结果产生负面影响。转化模型通过阐明软骨下骨重塑机制及其对软骨健康的关键影响，进一步支持了这些发现。本综述重点关注软骨下骨在骨软骨健康、损伤和OA方面的最新转化研究，强调在软骨修复过程中保持其完整性的必要性，并确保在OA治疗中考虑软骨下骨因素。了解软骨下骨改变可能会指导修复策略，包括旨在恢复骨软骨功能的生物疗法和基于生物材料的方法，为改善临床结果铺平道路。
