Department of Orthopaedic Surgery, University of California, San Francisco, San Francisco, California, U.S.A.; Department of Radiology and Biomedical Imaging and Center for Intelligent Imaging, University of California, San Francisco, San Francisco, California, U.S.A.
Department of Radiology and Biomedical Imaging and Center for Intelligent Imaging, University of California, San Francisco, San Francisco, California, U.S.A.
Arthroscopy. 2023 Jun;39(6):1493-1501.e2. doi: 10.1016/j.arthro.2022.11.040. Epub 2022 Dec 26.
To perform patellofemoral joint (PFJ) geometric measurements on knee magnetic resonance imaging scans and determine their relations with chondral lesions in a multicenter cohort using deep learning.
The sagittal tibial tubercle-trochlear groove (sTTTG) distance, tibial tubercle-trochlear groove distance, trochlear sulcus angle, trochlear depth, Caton-Deschamps Index (CDI), and flexion angle were measured by use of deep learning-generated segmentations on a subset of the Osteoarthritis Initiative study with radiologist-graded PFJ cartilage grades (n = 2,461). Kruskal-Wallis H tests were performed to compare differences in PFJ morphology between subjects without PFJ osteoarthritis (OA) and those with PFJ OA. PFJ morphology was correlated with secondary outcomes of mean patellar cartilage thickness and mean patellar cartilage T2 relaxation time using linear regression models controlling for age, sex, and body mass index.
A total of 1,626 knees did not have PFJ OA, whereas 835 knees had PFJ OA. Knees without PFJ OA had an increased (anterior) sTTTG distance (mean ± standard deviation, 11.1 ± 12.8 mm) compared with knees with PFJ OA (8.4 ± 12.7 mm) (P < .001), indicating a more posterior tibial tubercle in subjects with PFJ OA. Knees without PFJ OA had a decreased sulcus angle (127.4° ± 7.1° vs 128.0° ± 8.4°, P = .01) and increased trochlear depth (9.1 ± 1.7 mm vs 9.0 ± 2.0 mm, P = .03) compared with knees with PFJ OA. Decreased patellar cartilage thickness was associated with decreased trochlear depth (β = 0.12, P = .002) and increased CDI (β = -0.07, P < .001). Increased patellar cartilage T2 relaxation time was correlated with decreased sTTTG distance (β = -0.08, P = .01), decreased sulcus angle (β = -0.12, P = .04), and decreased CDI (β = -0.12, P < .001).
PFJ OA, patellar cartilage thickness, and patellar cartilage T2 relaxation time were shown to be associated with the underlying geometries within the PFJ. This large longitudinal study highlights that a decreased sTTTG distance (i.e., a more posterior tibial tubercle) is significantly associated with PFJ degenerative cartilage change.
Level III, retrospective comparative prognostic trial.
利用深度学习技术对膝关节磁共振成像扫描中的髌股关节（PFJ）进行几何测量，并在多中心队列中确定其与软骨损伤的关系。
在 Osteoarthritis Initiative 研究的一个亚组中，使用深度学习生成的分割来测量矢状胫骨结节-滑车沟（sTTTG）距离、胫骨结节-滑车沟距离、滑车沟角、滑车深度、Caton-Deschamps 指数（CDI）和屈曲角度（n=2461）。使用 Kruskal-Wallis H 检验比较无 PFJ 骨关节炎（OA）和有 PFJ OA 的 PFJ 形态差异。使用线性回归模型控制年龄、性别和体重指数，将 PFJ 形态与次要结局（平均髌骨软骨厚度和平均髌骨软骨 T2 弛豫时间）进行相关性分析。
共有 1626 个膝关节没有 PFJ OA，而 835 个膝关节有 PFJ OA。与有 PFJ OA 的膝关节相比，没有 PFJ OA 的膝关节的 sTTTG 距离（平均±标准差，11.1±12.8 mm）增加（前向）（P<.001），表明有 PFJ OA 的患者胫骨结节更靠后。与有 PFJ OA 的膝关节相比，没有 PFJ OA 的膝关节的滑车沟角（127.4°±7.1°比 128.0°±8.4°，P=.01）减小，滑车深度（9.1±1.7 mm 比 9.0±2.0 mm，P=.03）增加。髌骨软骨厚度减小与滑车深度减小（β=0.12，P=.002）和 CDI 增加（β=-0.07，P<.001）相关。髌骨软骨 T2 弛豫时间增加与 sTTTG 距离减小（β=-0.08，P=.01）、滑车沟角减小（β=-0.12，P=.04）和 CDI 减小（β=-0.12，P<.001）相关。
PFJ OA、髌骨软骨厚度和髌骨软骨 T2 弛豫时间与 PFJ 内的潜在几何形状相关。这项大型纵向研究表明，sTTTG 距离减小（即胫骨结节更靠后）与 PFJ 退行性软骨变化显著相关。
三级，回顾性比较预后试验。
