Department of Radiology, Stanford University, Stanford CA, USA.
Rigshospitalet, Copenhagen, Denmark.
Osteoarthritis Cartilage. 2022 Nov;30(11):1515-1525. doi: 10.1016/j.joca.2022.08.004. Epub 2022 Aug 27.
Altered joint function is a hallmark of osteoarthritis (OA). Imaging techniques for joint function are limited, but [F]sodium fluoride (NaF) PET-MRI may assess the acute joint response to loading stresses. [F]NaF PET-MRI was used to study the acute joint response to exercise in OA knees, and compare relationships between regions of increased uptake after loading and structural OA progression two years later.
In this prospective study, 10 participants with knee OA (59 ± 8 years; 8 female) were scanned twice consecutively using a PET-MR system and performed a one-legged squat exercise between scans. Changes in tracer uptake measures in 9 bone regions were compared between knees that did and did not exercise with a mixed-effects model. Areas of focally large changes in uptake between scans (ROI, ΔSUV > 3) were identified and the presence of structural MRI features was noted. Five participants returned two years later to assess structural change on MRI.
There was a significant increase in [F]NaF uptake in OA exercised knees (SUV P < 0.001, KP = 0.002, KP < 0.001) that differed by bone region.
There were regional differences in the acute bone metabolic response to exercise and areas of focally large changes in the metabolic bone response that might be representative of whole-joint dysfunction.
关节功能改变是骨关节炎（OA）的标志。关节功能的成像技术有限，但[F]氟化钠（NaF）PET-MRI 可评估负荷应激下关节的急性反应。[F]NaF PET-MRI 用于研究 OA 膝关节运动后的急性关节反应，并比较负荷后摄取增加区域与两年后结构 OA 进展之间的关系。
在这项前瞻性研究中，10 名膝关节 OA 患者（59±8 岁；8 名女性）连续两次使用 PET-MR 系统进行扫描，并在两次扫描之间进行单腿深蹲运动。使用混合效应模型比较两次扫描之间 9 个骨区示踪剂摄取变化的膝关节和不运动的膝关节。确定扫描之间摄取变化的局部大区域（ROI，ΔSUV > 3），并注意结构 MRI 特征的存在。5 名参与者在两年后返回，以评估 MRI 上的结构变化。
OA 运动膝关节的[F]NaF 摄取明显增加（SUV P < 0.001，KP = 0.002，KP < 0.001），不同骨区之间存在差异。
运动后骨代谢的急性反应存在区域差异，代谢性骨反应的局部大变化区域可能代表整个关节功能障碍。
