Murphy Eithne, Bresnihan Barry, FitzGerald Oliver
Department of Rheumatology, St. Vincent's University Hospital, Elm Park, Dublin 4, Ireland.
Clin Rheumatol. 2008 Jun;27(6):763-6. doi: 10.1007/s10067-007-0833-5. Epub 2008 Feb 21.
Hand bone densitometry is more sensitive than standard radiology in the measurement of disease-related bone damage in early arthritis. Most studies employing dual energy x-ray absorptiometry (DXA) have evaluated the whole hand. The aim of this study was to evaluate a method that quantified bone density in regions of interest that were confined to the juxta-articular areas of metacarpo-phalangeal (MCP) and proximal interphalangeal (PIP) joints. Patients with inflammatory arthritis affecting the hands were selected for study. Postero-anterior (PA) scans of selected juxta-articular sub-regions were acquired using a Hologic 4500 Elite bone densitometer and forearm software. Each hand was scanned three times in immediate succession with repositioning between scans. The six selected sub-regions included the periarticular regions of the second, third, and fourth MCP and PIP joints. Sub-regions of different dimensions (4 and 5 mm proximal and distal to the joint space) were assessed at each joint. Coefficients of variation (CV) were calculated for bone mineral density (BMD) and bone mineral content (BMC) of each selected sub-region. Eighty four individual hand joints in seven patients were evaluated three times. Precision values ranged between 0.89% and 2.37% for BMD and between 1.38 and 3.26 for BMC measurements. BMD measurements of MCP joints were more precise than PIP joints. BMD measurements of 10-mm sub-regions were more precise than 8-mm sub-regions. The precision value for the net average BMD measurement of the six sub-regions evaluated was 0.78% for 8-mm sub-regions and 0.73% for 10-mm sub-regions. Net average BMC measurements had CV values of 1.11% and 1.08%, respectively. DXA can be used to reliably measure periarticular BMD and BMC of small joints in the hands in patients with early inflammatory arthritis. Precision values for quantifying juxta-articular bone approximated BMD measurements of the spine.
在早期关节炎中，手部骨密度测量比标准放射学方法在检测与疾病相关的骨损伤方面更为敏感。大多数采用双能X线吸收法（DXA）的研究评估的是整个手部。本研究的目的是评估一种能够量化局限于掌指关节（MCP）和近端指间关节（PIP）近关节区域感兴趣区域骨密度的方法。选取手部患有炎性关节炎的患者进行研究。使用Hologic 4500 Elite骨密度仪和前臂软件获取选定近关节子区域的后前位（PA）扫描图像。每只手连续扫描三次，每次扫描之间重新定位。六个选定的子区域包括第二、第三和第四掌指关节及近端指间关节的关节周围区域。在每个关节评估不同尺寸（关节间隙近端和远端4毫米和5毫米）的子区域。计算每个选定子区域的骨矿物质密度（BMD）和骨矿物质含量（BMC）的变异系数（CV）。对7例患者的84个手部单个关节进行了三次评估。BMD测量的精密度值在0.89%至2.37%之间，BMC测量的精密度值在1.38至3.26之间。掌指关节的BMD测量比近端指间关节更精确。10毫米子区域的BMD测量比8毫米子区域更精确。评估的六个子区域的净平均BMD测量的精密度值，8毫米子区域为0.78%，10毫米子区域为0.73%。净平均BMC测量的CV值分别为1.11%和1.08%。DXA可用于可靠地测量早期炎性关节炎患者手部小关节的关节周围BMD和BMC。量化近关节骨的精密度值接近脊柱的BMD测量值。
