Department of Rheumatology, Leiden University Medical Center, Leiden, The Netherlands.
Department of Rheumatology, NOVA Medical School, Universidade Nova de Lisboa, Lisbon, Portugal.
Rheumatology (Oxford). 2022 Nov 28;61(12):4722-4730. doi: 10.1093/rheumatology/keac176.
In radiographic axial spondyloarthritis (r-axSpA), spinal damage manifests as syndesmophytes and facet joint ankylosis (FJA). We evaluated whether the presence of one lesion increased the risk of the other lesion.
Patients with r-axSpA underwent low-dose CT (ldCT) and MRI of the whole spine at baseline and 2 years. On ldCT, vertebrae were scored for presence and size of syndesmophytes; facet joints were assessed for ankylosis. MR images were assessed for inflammation. Two hypotheses were tested: (i) presence of FJA is associated with new syndesmophyte(s) on the same vertebral unit (VU) 2 years later, and (ii) presence of bridging syndesmophyte(s) is associated with new FJA on the same VU 2 years later. Two generalized estimating equations models were tested per hypothesis using increase of FJA/syndesmophytes (model A) or presence of FJA/syndesmophytes (model B) as outcome, adjusted for inflammation at baseline. Secondary analyses tested the hypotheses with outcomes on adjacent VUs and dose-response effects.
Fifty-one patients were included (mean age 49, 84% male, 82% HLA-B27+). Baseline bridging syndesmophytes occurred more often (range: 10-60% per VU) than FJA (range: 8-36%). Odds ratios (ORs) (95% CI) for presence of bridging syndesmophytes on development of FJA were 3.55 (2.03, 6.21) for model A and 3.30 (2.14, 5.09) for model B. ORs for presence of baseline FJA on new syndesmophytes were 1.87 (1.20, 2.92) for model A and 1.69 (0.88, 3.22) for model B. Secondary analyses yielded positive ORs for both hypotheses.
Bone formation in vertebrae and in facet joints influence each other's occurrence, with the effect of syndesmophytes being larger than that of FJA.
在放射性轴性脊柱关节炎（r-axSpA）中，脊柱损伤表现为骨桥和小关节融合（FJA）。我们评估了一种病变的存在是否会增加另一种病变的风险。
r-axSpA 患者在基线和 2 年时进行低剂量 CT（ldCT）和全脊柱 MRI。在 ldCT 上，对椎体的骨桥存在和大小进行评分；对小关节进行融合评估。MR 图像用于评估炎症。检验了两个假设：（i）FJA 的存在与同一椎骨单位（VU）2 年后新的骨桥有关，（ii）桥接骨桥的存在与同一 VU 2 年后新的 FJA 有关。每个假设使用增加的 FJA/骨桥（模型 A）或 FJA/骨桥的存在（模型 B）作为结果，使用基线炎症进行调整，使用两种广义估计方程模型进行检验。次要分析使用相邻 VU 和剂量反应效应的结果检验了这些假设。
共纳入 51 例患者（平均年龄 49 岁，84%为男性，82%为 HLA-B27+）。基线桥接骨桥的发生率高于 FJA（每个 VU 为 10-60%）（每个 VU 为 8-36%）。对于模型 A，存在桥接骨桥与 FJA 发展的比值比（OR）（95%CI）为 3.55（2.03，6.21），对于模型 B，为 3.30（2.14，5.09）。对于模型 A，存在基线 FJA 与新骨桥的比值比为 1.87（1.20，2.92），对于模型 B，为 1.69（0.88，3.22）。次要分析对两个假设都得出了阳性 OR。
椎体和小关节中的骨形成相互影响，骨桥的影响大于 FJA。
