Zhou Feng, Han Xuequan, Wang Liao, Zhang Weituo, Cui Junqi, He Zihao, Xie Kai, Jiang Xu, Du Jingke, Ai Songtao, Sun Qi, Wu Haishan, Yu Zhifeng, Yan Mengning
Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
J Orthop Translat. 2021 Dec 1;32:69-76. doi: 10.1016/j.jot.2021.11.002. eCollection 2022 Jan.
BACKGROUND/OBJECTIVE: Subchondral bone marrow lesions (BMLs) are common magnetic resonance imaging (MRI) features in joints affected by osteoarthritis (OA), however, their clinical impacts and mechanisms remain controversial. Thus, we aimed to investigate subchondral BMLs in knee OA patients who underwent total knee arthroplasty (TKA), then evaluate the associations of osteoclastogenesis and nerve growth in subchondral BMLs with clinical symptoms.
Total 70 patients with primary symptomatic knee OA were involved, then separated into three groups based on MRI (without BMLs group, n = 14; BMLs without cyst group, n = 37; BMLs with cyst group, n = 19). Volume of BMLs and cyst-like lesions was calculated via the OsiriX system. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was used to assess clinical symptoms. Histology and immunohistochemistry were deployed to assess subchondral osteoclastogenesis and nerve distribution. Pearson's correlation coefficient was used to evaluate the associations between volume of BMLs and joint symptoms, and to assess the associations of osteoclastogenesis and nerve growth in subchondral BMLs with joint symptoms.
In BMLs combined with cyst group, patients exhibited increased osteoclastogenesis and nerve distribution in subchondral bone, as shown by increased expression of tartrate resistant acid phosphatase (TRAP) and protein gene product 9.5 (PGP9.5). Volume of subchondral cyst-like component was associated with joint pain (p < 0.05). Subchondral osteoclastogenesis and nerve distribution were positively associated with joint pain in BMLs with cyst group (p < 0.05).
The subchondral cyst-like lesion was an independent factor for inducing pain in OA patients; osteoclastogenesis and nerve growth in subchondral cyst-like lesions could account for this joint pain.
Our results indicated that the increased osteoclastogenesis and nerve growth in subchondral cyst-like lesions could account for the pain of OA joints. These findings may provide valuable basis for the treatment of OA.
背景/目的：软骨下骨髓损伤（BMLs）是骨关节炎（OA）累及关节常见的磁共振成像（MRI）表现，但其临床影响及机制仍存在争议。因此，我们旨在研究接受全膝关节置换术（TKA）的膝骨关节炎患者的软骨下BMLs，进而评估软骨下BMLs中破骨细胞生成及神经生长与临床症状的相关性。
共纳入70例原发性症状性膝骨关节炎患者，根据MRI结果分为三组（无BMLs组，n = 14；无囊肿的BMLs组，n = 37；有囊肿的BMLs组，n = 19）。通过OsiriX系统计算BMLs和囊肿样病变的体积。采用西安大略和麦克马斯特大学骨关节炎指数（WOMAC）问卷评估临床症状。运用组织学和免疫组化方法评估软骨下破骨细胞生成及神经分布情况。采用Pearson相关系数评估BMLs体积与关节症状之间的相关性，以及软骨下BMLs中破骨细胞生成及神经生长与关节症状的相关性。
在有囊肿的BMLs组中，患者软骨下骨的破骨细胞生成及神经分布增加，表现为抗酒石酸酸性磷酸酶（TRAP）和蛋白基因产物9.5（PGP9.5）表达增加。软骨下囊肿样成分的体积与关节疼痛相关（p < 0.05）。在有囊肿的BMLs组中，软骨下破骨细胞生成及神经分布与关节疼痛呈正相关（p < 0.05）。
软骨下囊肿样病变是OA患者疼痛的独立诱发因素；软骨下囊肿样病变中的破骨细胞生成及神经生长可能是导致这种关节疼痛的原因。
我们的结果表明，软骨下囊肿样病变中破骨细胞生成及神经生长增加可能是OA关节疼痛的原因。这些发现可能为OA的治疗提供有价值的依据。
