Rapid assessment of 99mTc-pertechnetate uptake in the knee joint as a parameter of inflammatory activity.

Shortly after intravenous injection of 99mTechnetium-pertechnetate (99mTcO4-)(200 muCi), the activity of the knee joints was studied in patients with clinical arthritis of one or both knees and compared with that in normal subjects. A rest period directly before the study improved reproducibility. The values found shortly after injection were comparable with measurements at the maximum. The significance of the 99mTcO4- uptake in comparison with the histologic findings in cases of doubtful arthritis was examined.