We have read with interest the paper by Ridley et al¹ on the radiographic damage discordance between the sacroiliac joints (SIJs) and the spine in patients with ankylosing spondylitis (AS) from the Prospective Study of Outcomes in AS (PSOAS) cohort, which includes patients from the United States and Australia. Their results have encouraged us to investigate the prevalence of severe SIJ disease without evidence of concomitant syndesmophytes in the spine in our patient cohort from Spain.

中文翻译：

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分析强直性脊柱炎的性别差异：探索无脊柱受累的严重骶髂关节疾病背后的因素。

我们饶有兴趣地阅读了 Ridley 等人发表的论文¹，该论文涉及来自强直性脊柱炎 (PSOAS) 队列结果的前瞻性研究中的强直性脊柱炎 (AS) 患者的骶髂关节 (SIJ) 和脊柱之间的放射学损伤不一致，其中包括来自美国和澳大利亚的患者。他们的结果鼓励我们在西班牙患者队列中调查严重 SIJ 疾病的患病率，但没有证据表明脊柱中伴有韧带骨赘。