Increased 18F-FDG uptake suggests synovial inflammatory reaction with osteoarthritis

Abstract

The objective of this prospective study was to compare the metabolic activity of the knee joints of a group of subjects with painful knees clinically (as recurrent joint pain, joint instability and functional limitations) consistent with osteoarthritis (OA) and those of another group of patients without such complaints, using FDG-PET imaging. A total of 97 subjects who participated in either painful joint prosthesis or diabetic foot research studies involving FDG-PET scans were asked to complete a knee pain questionnaire. The patients were asked whether they experienced pain in any joint, and if so, which joints were affected. A total of 18 knee joints without prosthesis were reported to be painful. The maximum SUVs (SUVmax) of the middle joint space and lateral synovial tissue of these 18 knees were measured and compared to those of a set of subjects with control asymptomatic knees. The average SUVmax of the middle part of the joint space in the painful knees was 1.35 ± 0.59, as compared to an average SUVmax value of 0.86 ± 0.14 in the control group (p = 0.0176). The average SUVmax of the synovium in the lateral part of the painful joints was 1.17 ± 0.49, as compared to 0.73 ± 0.31 in the control group (p = 0.0161). These data indicate that increased FDG uptake is associated with knee pain in OA patients, and that there is a positive relationship between the two parameters.

Significance of incidental intra-articular and peri-articular FDG avid foci on PET/CT

“…Gout (5) and amyloidosis (6) have been shown to result in increased metabolic activity intra-articularly and in the peri-articular soft tissues. Symptomatic osteoarthritis has also been shown to produce increased FDG uptake (7) (Fig. 1).…”

18Fluorine‐fluorodeoxyglucose positron emission tomography for assessment of deep digital flexor tendinopathy: An exploratory study in eight horses with comparison to CT and MRI

“…20 Prospective studies have shown associated increased regional 18 F-FDG uptake with symptomatic (i.e., painful) knee and shoulder osteoarthritis in people. 21,22 A single case report confirmed that 18 F-FDG uptake in the Achilles tendon of a patient was due to active tendonitis, as confirmed by STIR hyperintensity in the same location on MR images. 23 Of most relevance to the equine patient, staging via 18 F-FDG PET has been used to assess healing of ruptured Achilles tendon after surgical repair in human athletes.…”

Intraarticular injection of a Tin‐117 m radiosynoviorthesis agent in normal canine elbows causes no adverse effects

“…This indicates the injection did not cause inflammation or damage to the joint, a finding that was supported by the histopathology on the joint tissues. Positron emission tomography imaging is a sensitive means to detect inflammation and has been validated for the evaluation of osteoarthritis . Positron emission tomography imaging may also be used to evaluate treatment response and to predict continued response in some cases.…”