Böttcher Joachim, Pfeil Alexander, Petrovitch Alexander, Schmidt Mirco, Kramer Anika, Schäfer Max Ludwig, Gajda Mieczyslaw, Hein Gert, Wolf Gunter, Kaiser Werner A
Institute of Diagnostic and Interventional Radiology, Friedrich Schiller University Jena Erlanger Allee, Jena, Germany;
Int J Biomed Sci. 2006 Sep;2(3):241-50.
To investigate Metacarpal Index (MCI) and Bone Mineral Density (BMD) estimated by Digital X-ray Radiogrammetry (DXR) with respect to its ability to quantify severity-dependent variations of bone mineralisation in patients with early rheumatoid arthritis compared to Dual Energy X-ray Absorptiometry (DXA), 122 patients underwent a prospective analysis of BMD and MCI by DXR, whereas both DXR-parameters were estimated from plain radiographs of the non-dominant hand. In comparison DXA measured BMD on total femur and lumbar spine (L2-L4). Additionally Steinbrocker Stage was assessed to differentiate the severity of rheumatoid arthritis (RA). Disease activity of RA was estimated by C-reactive Protein (CRP; in mg/l), Erythrocyte Sedimentation Rate (ESR in mm/1st hour) and by the disease activity score with 28-joint count (DAS 28). In consequence, The DXR-parameters, in particular DXR-MCI, revealed significant associations to age, Body Mass Index, CRP, DAS 28 and Steinbrocker graduation; no significant associations could be verified between DXA-parameters and all characteristics of disease activity and severity of RA. The highest correlation was found between DXR-MCI and DXR-BMD with R=0.89 (independent from severity of RA). In all patients DXR-MCI significantly decreased (-14.3%) from 0.42 ± 0.09 (stage 1) to 0.36 ± 0.07 (stage 2) dependent on severity of RA. The comparable relative reduction of DXR-BMD was -11.1%. The group of patients with minor disease activity (DAS 28>5.1) showed a significant flattened reduction (-11.4%) for DXR-MCI from 0.44 ± 0.08 (stage 1) to 0.39 ± 0.08 (stage 2). For accentuated disease activity (DAS 28>5.1) the DXR-MCI revealed a pronounced reduction (-23.1 %). No significant declines were observed for DXA-BMD of the lumbar spine and total femur in all patients as well as dependent on disease activity.
DXR can exactly quantify cortical thinning of the metacarpal bones and can identify cortical demineralisation in patients suffering from early rheumatoid arthritis surpassing DXA-measurements at axial bone sites. In this context DXR-MCI seems to be the most sensitive parameter for differentiation of patients with minor or accentuated disease activity following severity-dependent cortical bone loss.
为研究数字X线摄影测量法（DXR）评估的掌骨指数（MCI）和骨密度（BMD）在量化早期类风湿关节炎患者骨矿化程度依赖性变化方面的能力，并与双能X线吸收法（DXA）进行比较，122例患者接受了DXR对BMD和MCI的前瞻性分析，而这两个DXR参数均从非优势手的平片估算得出。相比之下，DXA测量了全股骨和腰椎（L2-L4）的BMD。此外，评估了斯坦布鲁克分期以区分类风湿关节炎（RA）的严重程度。通过C反应蛋白（CRP；单位为mg/l）、红细胞沉降率（ESR；单位为mm/第1小时）以及28个关节计数的疾病活动评分（DAS 28）来评估RA的疾病活动度。结果显示，DXR参数，尤其是DXR-MCI，与年龄、体重指数、CRP、DAS 28和斯坦布鲁克分级存在显著关联；而DXA参数与RA疾病活动度和严重程度的所有特征之间未证实有显著关联。DXR-MCI与DXR-BMD之间的相关性最高，R=0.89（与RA严重程度无关）。在所有患者中，DXR-MCI随着RA严重程度从第1阶段的0.42±0.09显著下降（-14.3%）至第2阶段的0.36±0.07。DXR-BMD的可比相对降幅为-11.1%。疾病活动度较轻（DAS 28>5.1）的患者组中，DXR-MCI从第1阶段的0.44±0.08显著平缓下降（-11.4%）至第2阶段的0.39±0.08。对于疾病活动度较重（DAS 28>5.1）的患者，DXR-MCI有显著下降（-23.1%）。所有患者以及根据疾病活动度，腰椎和全股骨的DXA-BMD均未观察到显著下降。
DXR能够准确量化掌骨皮质变薄情况，并能识别早期类风湿关节炎患者的皮质脱矿，优于轴向骨部位的DXA测量。在此背景下，DXR-MCI似乎是区分疾病活动度较轻或较重患者的最敏感参数，这些患者存在程度依赖性皮质骨丢失。
