Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Japan.
Spine (Phila Pa 1976). 2011 Apr 15;36(8):647-53. doi: 10.1097/BRS.0b013e3181da21c5.
A 5-year prospective cohort study of cervical spine instabilities in rheumatoid arthritis (RA). OBJECTIVE.: To clarify the natural course of cervical instabilities in RA patients and to determine predictors for the prognosis of RA cervical spine.
Although several previous studies investigating the natural history of RA cervical spine have been reported, few of them have described radiological predictive factors for the aggravation of these instabilities.
Two hundred sixty-seven outpatients with "definite" or "classical" RA initially assigned were prospectively followed for over 5 years. Radiographic cervical findings were classified into three representative instabilities: atlantoaxial subluxation (AAS), vertical subluxation (VS), and subaxial subluxation (SAS). The aggravations of these instabilities were identified in the cases with a decrease of at least 2 mm in the Ranawat value of VS, an increase of at least 1 mm in translation of SAS, or a new development of respective instabilities. RA stages and mutilating changes were assessed in the hand radiograms.
Fifty-two point four percent of 267 patients, without any cervical instability at the beginning of follow-up, decreased to 29.6% at the end (P < 0.01), whereas VS and SAS increased significantly (P < 0.01). The aggravation of VS was observed at statistically higher rates in patients with pre-existing instabilities as follows; 25.7% of AAS (P = 0.01), 49.1% of VS (P < 0.01), and 41.2% of SAS (P = 0.06). The aggravation of SAS was also detected in 47.2% of VS and 64.7% of SAS (P < 0.01). Patients with pre-existing mutilating changes exhibited the aggravations of VS and SAS in significantly higher incidences (P < 0.01). Furthermore, the cases with development into mutilating changes during the follow-up showed significantly higher tendencies for the aggravations of these instabilities (P < 0.01).
The incidences of VS and SAS significantly increased during the minimum 5-year follow-up. Prognostic factors of these instabilities were revealed to be the initial radiological findings of VS, SAS, and mutilating changes.
类风湿关节炎（RA）颈椎失稳的 5 年前瞻性队列研究。目的：阐明 RA 患者颈椎失稳的自然病程，并确定 RA 颈椎预后的预测因素。
尽管已经有几项关于 RA 颈椎自然史的研究报告，但其中很少有描述这些失稳加重的放射学预测因素。
267 例“明确”或“经典”RA 初诊患者前瞻性随访超过 5 年。颈椎影像学表现分为三种代表性失稳：寰枢关节半脱位（AAS）、垂直半脱位（VS）和下颈椎半脱位（SAS）。在 VS 的 Ranawat 值至少减少 2mm、SAS 的平移至少增加 1mm 或出现各自失稳的新发展的情况下，确定这些失稳的加重。在手 X 线片上评估 RA 分期和致残改变。
267 例患者中，52.4%在随访开始时无任何颈椎失稳，在随访结束时降至 29.6%（P < 0.01），而 VS 和 SAS 显著增加（P < 0.01）。在存在先前失稳的患者中，VS 加重的发生率更高，如下所示：AAS 占 25.7%（P = 0.01）、VS 占 49.1%（P < 0.01）、SAS 占 41.2%（P = 0.06）。SAS 的加重也在 47.2%的 VS 和 64.7%的 SAS 中发现（P < 0.01）。有先前致残改变的患者，VS 和 SAS 加重的发生率明显更高（P < 0.01）。此外，在随访期间发展为致残改变的病例，这些失稳加重的趋势明显更高（P < 0.01）。
在至少 5 年的随访中，VS 和 SAS 的发生率显著增加。这些失稳的预测因素是 VS、SAS 和致残改变的初始影像学表现。
