Kuroki Hiroshi, Nakagawa Yasuaki, Mori Koji, Kobayashi Masahiko, Yasura Ko, Okamoto Yukihiro, Suzuki Takashi, Nishitani Kohei, Nakamura Takashi
Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Shogoin, Kyoto, Japan.
Arthritis Res Ther. 2008;10(4):R78. doi: 10.1186/ar2452. Epub 2008 Jul 13.
There is a lack of data relating the macroscopic appearance of cartilage to its ultrasound properties. The purpose of the present study was to evaluate degenerated cartilage and healthy-looking cartilage using an ultrasound system.
Ultrasound properties--signal intensity (a measure of superficial cartilage integrity), echo duration (a parameter related to the surface irregularity) and the interval between signals (that is, time of flight--which is related to the thickness and ultrasound speed of cartilage)--of 20 knees were measured at seven sites: the lateral femoral condyle (site A, anterior; site B, posterior), the medial condyle (site C), the lateral tibial plateau (site D, center; site E, under the meniscus) and the medial tibial plateau (site F, anterior; site G, posterior). The sites were evaluated macroscopically and classed using the International Cartilage Repair Society (ICRS) grading system.
The signal intensity of grade 0 cartilage was significantly greater than the intensities of grade 1, grade 2 or grade 3 cartilage. Signal intensity decreased with increasing ICRS grades. The signal intensity was greater at site B than at site C, site D, site F and site G. The signal intensity of grade 0 was greater at site B than at site E. The echo duration did not differ between the grades and between the sites. The interval between signals of grade 3 was less than the intervals of grade 0, grade 1 or grade 2. The interval between signals at site C was less than the intervals at site A, site B, site D, and site E.
Site-specific differences in signal intensity suggest that a superficial collagen network may be maintained in cartilage of the lateral condyle but may deteriorate in cartilage of the medial condyle and the medial tibial plateau in varus knee osteoarthritis. Signal intensity may be helpful to differentiate ICRS grades, especially grade 0 cartilage from grade 1 cartilage.
目前缺乏有关软骨宏观外观与其超声特性之间关系的数据。本研究的目的是使用超声系统评估退变软骨和外观正常的软骨。
在20个膝关节的7个部位测量超声特性——信号强度（一种衡量表层软骨完整性的指标）、回声持续时间（一个与表面不规则性相关的参数）以及信号之间的间隔（即飞行时间——与软骨的厚度和超声速度相关），这些部位包括：外侧股骨髁（A点，前部；B点，后部）、内侧髁（C点）、外侧胫骨平台（D点，中央；E点，半月板下方）以及内侧胫骨平台（F点，前部；G点，后部）。对这些部位进行宏观评估，并使用国际软骨修复协会（ICRS）分级系统进行分类。
0级软骨的信号强度显著高于1级、2级或3级软骨的信号强度。信号强度随着ICRS分级的增加而降低。B点的信号强度高于C点、D点、F点和G点。0级软骨在B点的信号强度高于E点。各分级之间以及各部位之间的回声持续时间没有差异。3级软骨的信号间隔小于0级、1级或2级软骨的信号间隔。C点的信号间隔小于A点、B点、D点和E点的信号间隔。
信号强度的部位特异性差异表明，在膝内翻骨关节炎中，外侧髁软骨中的表层胶原网络可能得以维持，但内侧髁和内侧胫骨平台的软骨中的表层胶原网络可能会退化。信号强度可能有助于区分ICRS分级，尤其是0级软骨和1级软骨。
