Liao Simin, Cheng Liuquan, Zhao Zheng, Zhu Jian, Huang Feng
Department of Rheumatology and Immunology, The First Medical Center of Chinese PLA General Hospital, Beijing, China.
Department of Radiology, The Sixth Medical Center of Chinese PLA General Hospital, Beijing, China.
Ther Adv Musculoskelet Dis. 2024 Sep 28;16:1759720X241281201. doi: 10.1177/1759720X241281201. eCollection 2024.
Both vertebral bodies and posterior elements of the vertebrae (facet joints, FJ) can engage in bone formation in radiographic axial spondyloarthritis (r-axSpA). However, little is known about the specific structural lesions and progression patterns of FJs in r-axSpA.
To identify specific lesions related to r-axSpA and to investigate the distinct progression patterns by comparing the FJ changes of r-axSpA with that of diffuse idiopathic skeletal hyperostosis (DISH), osteoarthritis (OA), and control group (CG).
Single-center, retrospective study. Longitudinal imaging data were retrieved and collected.
Age- and sex-matched patients with complete thoracic and lumbar spine computed tomography (CT) data were included and their bilateral FJs were assessed. FJ changes were divided into erosions, ankylosis, joint-space narrowing, osteophytes, subchondral sclerosis, subchondral cysts, and vacuum phenomena. Average progressed year was defined as "number of changed vertebrae × interval years"/number of changed vertebrae.
In all, 50 patients in each group were included. Subchondral cysts and vacuum phenomena were not observed. Bilateral FJ ankylosis (FJA)/erosions in the thoracic and lumbar spine, and unilateral ankylosis/erosions in T1-4, T9-12 were significantly more common in r-axSpA. Joint-space narrowing/osteophytes/subchondral sclerosis were significantly more common in DISH and OA. FJ lesions progressed in 56.34% of vertebrae of r-axSpA. The most common pattern was "FJ normal advanced to ankylosis" (17.54%) which required 2.63 years. It was followed by "erosions advanced to ankylosis" (12.3%) which took 2.05 years, and by "normal FJ advanced to erosions" (11.04%) which took 2.29 years, respectively. Degenerative changes could also progress to FJ erosions/ankylosis (24.83%). The majority pattern in DISH/OA was "FJ changes advanced to subchondral sclerosis/osteophytes/joint-space narrowing."
Bilateral FJA/erosions are r-axSpA-specific lesions. The specific progression pattern for r-axSpA was "FJ changes advanced to ankylosis/erosions." Repeated CT examination in intervals of at least 2 years will be more appropriate for monitoring FJ progression.
在影像学轴向脊柱关节炎（r-axSpA）中，椎体和椎骨的后部结构（小关节，FJ）均可参与骨形成。然而，关于r-axSpA中小关节的具体结构病变和进展模式知之甚少。
通过比较r-axSpA与弥漫性特发性骨肥厚（DISH）、骨关节炎（OA）及对照组（CG）的小关节变化，确定与r-axSpA相关的特定病变，并研究其不同的进展模式。
单中心回顾性研究。检索并收集纵向影像数据。
纳入年龄和性别匹配且有完整胸腰椎计算机断层扫描（CT）数据的患者，并对其双侧小关节进行评估。小关节变化分为侵蚀、强直、关节间隙变窄、骨赘、软骨下硬化、软骨下囊肿及真空现象。平均进展年定义为“椎体变化数×间隔年数”/椎体变化数。
每组共纳入50例患者。未观察到软骨下囊肿和真空现象。r-axSpA患者胸腰椎双侧小关节强直（FJA）/侵蚀以及T1-4、T9-12单侧强直/侵蚀更为常见。关节间隙变窄/骨赘/软骨下硬化在DISH和OA中更为常见。r-axSpA患者56.34%的椎体出现小关节病变进展。最常见的模式是“小关节正常进展为强直”（17.54%），需要2.63年。其次是“侵蚀进展为强直”（12.3%），耗时2.05年，以及“小关节正常进展为侵蚀”（11.04%），耗时2.29年。退变改变也可进展为小关节侵蚀/强直（24.83%）。DISH/OA的主要模式是“小关节变化进展为软骨下硬化/骨赘/关节间隙变窄”。
双侧FJA/侵蚀是r-axSpA的特异性病变。r-axSpA的特定进展模式是“小关节变化进展为强直/侵蚀”。至少每2年进行一次重复CT检查更适合监测小关节进展。
