Eckstein Felix, Wirth Wolfgang, Hudelmaier Martin, Stein Verena, Lengfelder Verena, Cahue September, Marshall Meredith, Prasad Pottumarthi, Sharma Leena
Paracelsus Medical University, Salzburg, Austria.
Arthritis Rheum. 2008 Nov 15;59(11):1563-70. doi: 10.1002/art.24208.
Malalignment is known to alter medial-to-lateral femorotibial load distribution and to affect osteoarthritis (OA) progression in the mechanically stressed compartment. We investigated the pattern of cartilage loss in neutral, varus, and valgus knees.
Alignment was measured from full-limb radiographs in 174 participants with symptomatic knee OA. Coronal magnetic resonance images were acquired at baseline and a mean +/- SD of 26.6 +/- 5.4 months later. The weight-bearing femorotibial cartilages were segmented from paired images. Cartilage volume, surface area, and thickness were determined in total cartilage plates and defined subregions using proprietary software.
The medial-to-lateral ratio of femorotibial cartilage loss was 1.4:1 in neutral knees (n = 74), 3.7:1 in varus knees (n = 57), and 1:6.0 in valgus knees (n = 43). The relative contribution of cartilage thickness change tended to be greater in knees with mild cartilage loss, whereas the increase of denuded area was greater in knees with accelerated cartilage loss. In both varus and neutral knees, the greatest changes were observed in the same subregions of the medial femorotibial compartment (central and external medial tibia, and central medial femur). In valgus and neutral knees, the subregions with the greatest changes in the lateral femorotibial compartment were also similar (internal and central lateral tibia, external lateral femur).
The medial-to-lateral rate of femorotibial cartilage loss strongly depended on alignment. Subregions of greater-than-average cartilage loss within the stressed compartment were, however, similar in neutral, varus, and valgus knees. This indicates that the medial-to-lateral loading pattern is different, but that the (sub)regional loading pattern may not differ substantially between neutral and malaligned knees.
已知力线不良会改变股骨胫股关节内外侧的负荷分布，并影响机械应力作用关节间室骨关节炎（OA）的进展。我们研究了中立位、内翻和外翻膝关节软骨损伤的模式。
对174例有症状的膝关节OA患者的全下肢X线片进行力线测量。在基线时以及平均26.6±5.4个月后采集冠状面磁共振成像。从配对图像中分割出负重的股骨胫股关节软骨。使用专用软件确定总软骨板以及定义的子区域中的软骨体积、表面积和厚度。
中立位膝关节（n = 74）的股骨胫股关节软骨内外侧损失比例为1.4:1，内翻膝关节（n = 57）为3.7:1，外翻膝关节（n = 43）为1:6.0。软骨厚度变化的相对贡献在软骨轻度损伤的膝关节中往往更大，而在软骨损伤加速的膝关节中裸露面积的增加更大。在内翻和中立位膝关节中，股骨胫股关节内侧间室的相同子区域变化最大（胫骨内侧中央和外侧以及股骨内侧中央）。在外翻和中立位膝关节中，股骨胫股关节外侧间室变化最大的子区域也相似（胫骨外侧内侧和中央、股骨外侧外侧）。
股骨胫股关节软骨内外侧损失率很大程度上取决于力线。然而，在应力作用的关节间室内，软骨损失大于平均水平的子区域在中立位、内翻和外翻膝关节中是相似的。这表明股骨胫股关节内外侧的负荷模式不同，但中立位和力线不良的膝关节之间（子）区域负荷模式可能没有实质性差异。
