University of Kansas Medical Center, Kansas City, KS, USA; The University of Iowa, Iowa City, IA, USA.
University of California-San Francisco, San Francisco, CA, USA.
Osteoarthritis Cartilage. 2023 Mar;31(3):406-413. doi: 10.1016/j.joca.2022.12.002. Epub 2022 Dec 13.
Radiographic joint space width (JSW) has been a standard for measuring knee osteoarthritis (OA) structural change. Limitations in the responsiveness of this approach might be overcome by instead measuring 3D JSW on weight-bearing CT (WBCT). This study compared the responsiveness of 3D JSW measurements using WBCT with the responsiveness of radiographic 2D JSW.
Standing, fixed-flexion knee radiographs (XR) and WBCT were acquired ancillary to the 144- and 168-month Multicenter Osteoarthritis Study visits. Tibiofemoral JSW was measured on both XR and WBCT. Responsiveness to change was defined by the standardized response mean (SRM) for change in JSW (1) at predetermined mediolateral locations (JSWx) on both modalities and (2) in the following subregions measured on WBCT images: central medial and lateral femur (CMF/CLF) and tibia (CMT/CLT), and anterior and posterior tibia (AMT/ALT, PMT/MLT).
Baseline and 24-month follow-up JSWx measurements were completed for 265 participants (58.1% women). Responsiveness of 3D JSWx for medial tibiofemoral compartment on coronal WBCT (SRM range: -0.18, -0.24) exceeded that for 2D JSWx (-0.10, -0.16). Responsiveness of 3D JSW subregional mean (-0.06, -0.36) and maximal (-1.14, -1.75) CMF and CMT and maximal CLF/CLT 3D JSW changes were statistically significantly greater in comparison with respective medial and lateral 2D JSWx (P ≤ 0.002).
Subregional 3D JSW on WBCT is substantially more responsive to 24-month changes in tibiofemoral joint structure compared to radiographic measurements. Use of subregional 3D JSW on WBCT could enable improved detection of OA structural progression over a 24-month duration in comparison with measurements made on XR.
放射学关节间隙宽度（JSW）一直是衡量膝关节骨关节炎（OA）结构变化的标准。通过在负重 CT（WBCT）上测量 3D JSW，可能会克服这种方法的反应性局限性。本研究比较了使用 WBCT 测量 3D JSW 的反应性与放射学 2D JSW 的反应性。
在 144 个月和 168 个月的多中心骨关节炎研究访问期间，获得了站立、固定弯曲膝关节 X 射线（XR）和 WBCT。在 XR 和 WBCT 上测量胫股 JSW。通过 JSW 变化的标准化反应均值（SRM）定义对变化的反应性（1）在两种模态上预定的内外侧位置（JSWx），以及（2）在 WBCT 图像上测量的以下子区域：中央内侧和外侧股骨（CMF/CLF）和胫骨（CMT/CLT），以及胫骨前和后（AMT/ALT，PMT/MLT）。
265 名参与者（58.1%为女性）完成了基线和 24 个月随访 JSWx 测量。冠状 WBCT 上内侧胫股关节 3D JSWx 的反应性（SRM 范围：-0.18，-0.24）超过 2D JSWx（-0.10，-0.16）。3D JSW 子区域平均值（-0.06，-0.36）和最大值（-1.14，-1.75）CMF 和 CMT 以及最大的 CLF/CLT 3D JSW 变化的反应性显著大于相应的内侧和外侧 2D JSWx（P≤0.002）。
与放射学测量相比，WBCT 上的 3D JSW 子区域在 24 个月内对胫股关节结构的变化更敏感。与 XR 上的测量相比，在 WBCT 上使用 3D JSW 子区域可以在 24 个月的时间内更好地检测 OA 结构进展。
