Microdensity of solitary bone cyst after steroid injection.

The change of bone density in five patients with solitary bone cysts (SBC) was directly measured by microdensitometry (MD). Standard plain radiographs could not always predict the strength of the bone, but with MD, smaller changes in bone density could be found quantitatively. The density of the lesion temporarily decreased just after steroid injection and began to increase to maximum level in approximately 4 or 5 months. However, in two patients, the density decreased gradually to the first MD levels and refractured. In this article we stress the usefulness of direct MD in detecting the strength of the lesion.