Institute of Anatomy and Musculoskeletal Research, Paracelsus Medical University, Salzburg, Austria.
Osteoarthritis Cartilage. 2011 Jan;19(1):74-83. doi: 10.1016/j.joca.2010.10.022. Epub 2010 Oct 31.
To compare femorotibial cartilage thickness changes over a 2- vs a 1-year observation period in knees with radiographic knee osteoarthritis (OA).
One knee of 346 Osteoarthritis Initiative (OAI) participants was studied at three time points [baseline (BL), year-1 (Y1), year-2 (Y2) follow-up]: 239 using coronal fast low angle shot (FLASH) and 107 using sagittal double echo at steady state (DESS) MR imaging. Changes in cartilage thickness were assessed in femorotibial cartilage plates and subregions, after manual segmentation with blinding to time-point.
The standardized response mean (SRM) of total joint cartilage thickness over 2 years was modestly higher than over 1 year (FLASH: -0.44 vs -0.32/-0.28 [first/second year]; DESS: -0.42 vs -0.39/-0.18). For the subregion showing the largest change per knee (OV1), the 2-year SRM was similar or lower (FLASH: -1.20 vs -1.22/-1.61; DESS: -1.38 vs -1.64/-1.51) than the 1-year SRM. The changes in total joint cartilage thickness were not significantly different in the first and second year (FLASH: -0.8% vs -0.7%; DESS: -1.3% vs -0.8%) and were negatively correlated. Analysis of smallest detectable changes (SDCs) revealed that only few participants displayed significant progression in both consecutive periods. The location of the subregion contributing to OV1 in each knee was highly inconsistent between the first and second year observation period.
The SRM of region-based cartilage thickness change in OA is modestly larger following a 2-year vs a 1-year observation period, while it is relatively similar when an OV-approach is chosen. Structural progression displays strong temporal and spatial heterogeneity at an individual knee level that should be considered when planning clinical trials.
比较膝关节影像学骨关节炎（OA）患者在 2 年与 1 年观察期内的髌股软骨厚度变化。
对 346 名 Osteoarthritis Initiative（OAI）参与者的 1 只膝关节进行了 3 个时间点（基线（BL）、第 1 年（Y1）和第 2 年（Y2）随访）的研究：239 例使用冠状位快速低角采集（FLASH），107 例使用矢状位稳态双回波（DESS）MR 成像。通过盲法对时间点进行手动分割后，评估髌股软骨板和子区域的软骨厚度变化。
2 年总关节软骨厚度的标准化反应均值（SRM）略高于 1 年（FLASH：-0.44 比-0.32/-0.28[第 1 年/第 2 年]；DESS：-0.42 比-0.39/-0.18）。对于每个膝关节变化最大的子区域（OV1），2 年 SRM 相似或更低（FLASH：-1.20 比-1.22/-1.61；DESS：-1.38 比-1.64/-1.51）。在第 1 年和第 2 年，总关节软骨厚度的变化没有显著差异（FLASH：-0.8%比-0.7%；DESS：-1.3%比-0.8%），并且呈负相关。最小可检测变化（SDC）分析表明，只有少数参与者在两个连续时期都显示出明显的进展。在第 1 年和第 2 年观察期间，每个膝关节的子区域导致 OV1 的位置高度不一致。
在 OA 中，基于区域的软骨厚度变化的 SRM 在 2 年观察期内略大于 1 年观察期，但当选择 OV 方法时，它相对相似。在个体膝关节水平上，结构进展显示出强烈的时间和空间异质性，在规划临床试验时应予以考虑。
