Department of Radiology, University of California-San Diego, La Jolla, CA, USA.
Department of Radiology, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand.
Skeletal Radiol. 2020 Dec;49(12):2019-2027. doi: 10.1007/s00256-020-03517-6. Epub 2020 Jun 26.
To compare regional differences in subchondral trabecular structure using high-resolution MRI in meniscus-covered/meniscus-uncovered tibia in cadaveric knees with intact/torn menisci.
3D proton density CUBE MRI of 6 cadaveric knees without significant osteoarthritis (OA) was acquired, 0.25-mm resolution. Menisci were evaluated and classified intact or torn. MR data were transferred to ImageJ program to segment tibial 3D volume of interest (VOI). Data was subdivided into meniscus-covered/meniscus-uncovered regions. Segmented VOI was classified into binary data, trabeculae/bone marrow. The trabecular bone data was used to measure MR biomarkers (apparent subchondral plate-connected bone density (adapted from spine MR), apparent trabecular bone volume fraction, apparent mean trabecular thickness, apparent connectivity density, and structure model index (SMI)). Mean value of parameters was analyzed for the effects of meniscal tear/tibial coverage.
Nine torn menisci and 3 intact menisci were present. MR measures of bone varied significantly due to meniscal coverage/tear. Subchondral plate-connected bone density under covered meniscus regions increased from 10.9 to 23.5% with meniscal tear. Values increased in uncovered regions, 19.3% (intact) and 32.4% (torn). This reflects higher density when uncovered (p = 0.048) with meniscal tear (p = 0.007). Similar patterns were found for trabecular bone fraction (coverage p < 0.001, tear p = 0.047), trabecular thickness (coverage p = 0.03), connectivity density (coverage p = 0.002), and SMI (coverage p = 0.015).
Quantitative trabecular bone evaluation emphasizes intrinsic structural differences between meniscus-covered/meniscus-uncovered tibias. Results offer insight into bone adaptation with meniscal tear and support the hypothesis that subchondral bone plate-connected bone density could be important in early subchondral bone adaptation.
比较半月板覆盖/未覆盖胫骨的关节下骨小梁结构的区域差异，使用完整/撕裂半月板的尸体膝关节的高分辨率 MRI。
对 6 例无明显骨关节炎（OA）的尸体膝关节进行了 3D 质子密度 CUBE MRI 采集，分辨率为 0.25 毫米。评估并分类半月板完整或撕裂。将 MR 数据传输到 ImageJ 程序以分割胫骨 3D 感兴趣区（VOI）。数据分为半月板覆盖/未覆盖区域。将分割的 VOI 分为二值数据，小梁/骨髓。使用小梁骨数据测量 MR 生物标志物（改编自脊柱 MRI 的骨密度、表观骨小梁体积分数、表观平均骨小梁厚度、表观连接密度和结构模型指数（SMI））。分析了参数的平均值，以研究半月板撕裂/胫骨覆盖的影响。
9 个撕裂半月板和 3 个完整半月板。由于半月板覆盖/撕裂，骨的 MR 测量值差异显著。覆盖半月板区域的骨密度从有半月板撕裂时的 10.9%增加到 23.5%。未覆盖区域的骨密度增加，分别为 19.3%（完整）和 32.4%（撕裂）。这表明在没有半月板覆盖时骨密度更高（p=0.048），且有半月板撕裂时骨密度更高（p=0.007）。骨小梁分数（覆盖 p<0.001，撕裂 p=0.047）、骨小梁厚度（覆盖 p=0.03）、连接密度（覆盖 p=0.002）和 SMI（覆盖 p=0.015）也呈现出类似的模式。
定量小梁骨评估强调了半月板覆盖/未覆盖胫骨之间的固有结构差异。结果为半月板撕裂时的骨适应性提供了深入了解，并支持关节下骨密度可能是早期关节下骨适应性的重要因素的假设。
