Kuster M S, Podsiadlo P, Stachowiak G W
Klinik für Orthopädische Chirurgie, Kantonsspital, St Gallen, Switzerland.
Br J Rheumatol. 1998 Sep;37(9):978-84. doi: 10.1093/rheumatology/37.9.978.
To analyse and compare the shape of wear particles found in healthy and osteoarthritic human knee joints for monitoring the progress of osteoarthritis, the long-term prognosis and to evaluate therapeutic regimens.
Joint particles from seven patients with normal cartilage in all compartments of the knee joint, 12 patients with fibrillation of less than half the cartilage thickness (grade 1), seven patients with fibrillation of more than half the cartilage thickness (grade 2) and four patients with erosions down to bone (grade 3) were analysed. A total of 565 particles were extracted from synovial fluid samples by ferrography and analysed in a scanning electron microscope. A number of numerical descriptors, i.e. boundary fractal dimension, shape factor, convexity and elongation, were calculated for each particle image and correlated to the degree of osteoarthritis using non-parametric tests.
Experiments demonstrated that there were significant differences between the numerical descriptors calculated for wear particles from healthy and osteoarthritic knee joints (P < 0.01), suggesting that the particle shape can be used as an indicator of the joint condition. In particular, the fractal dimension of the particle boundary was shown to correlate directly with the degree of osteoarthritis.
Numerical analysis of the shape of wear particles found in human knee joints may provide a reliable means for the assessment of cartilage repair after surgical or conservative treatment of osteoarthritis.
分析和比较在健康及骨关节炎患者膝关节中发现的磨损颗粒的形状，以监测骨关节炎的进展、长期预后并评估治疗方案。
分析了来自7例膝关节各腔室软骨正常的患者、12例软骨纤维化厚度小于一半（1级）的患者、7例软骨纤维化厚度大于一半（2级）的患者以及4例骨侵蚀（3级）患者的关节颗粒。通过铁谱分析从滑液样本中总共提取了565个颗粒，并在扫描电子显微镜下进行分析。为每个颗粒图像计算了一些数值描述符，即边界分形维数、形状因子、凸度和伸长率，并使用非参数检验将其与骨关节炎程度相关联。
实验表明，健康膝关节和骨关节炎膝关节磨损颗粒的数值描述符之间存在显著差异（P < 0.01），这表明颗粒形状可作为关节状况的指标。特别是，颗粒边界的分形维数显示与骨关节炎程度直接相关。
对人膝关节中发现的磨损颗粒形状进行数值分析，可能为骨关节炎手术或保守治疗后软骨修复的评估提供一种可靠的方法。
