Quantitative bone scintigraphy in reflex sympathetic dystrophy.

We have investigated the appearances of the technetium-99m labelled methylene diphosphonate bone scan in 29 scans performed in 16 patients with post-fracture reflex sympathetic dystrophy (RSD) of the hand. There was a close correlation between increased uptake in the metacarpophalangeal joints and the metacarpal bones, suggesting that the increased uptake in RSD is not confined to the periarticular areas as has been previously reported but occurs throughout the affected region. In seven cases examined 3 months after fracture, RSD was associated with a significant increase in uptake at all sites in the hand on the delayed scan which was not seen in matched post-fracture controls, confirming that increased uptake on delayed bone scintography is a sensitive test for the presence of RSD even in the presence of a fracture of the wrist. The early increased uptake gradually returned to normal. Local tenderness assessed by dolorimetry was correlated with increased uptake, suggesting that the bone scan is not only useful as a diagnostic tool but also provides a quantitative indication of the severity of the condition which may be useful in planning and assessing treatments.