Radionuclide joint imaging.

Modern radionuclide techniques of joint imaging involve the use of either 99mTc-pertechnetate or 99mTc-phosphate compounds in conjunction with the Anger camera. In general, images obtained with both types of radiocompound are nonspecific--although increased uptake of 99mTc-pertechnetate usually denotes the presence of synovitis. The most popular uses of the technique are in documenting the extent and severity of inflammatory joint disease, assessing the effect of therapy, and establishing the diagnoses of Legg-Perthes disease and septic arthritis. The method is also useful in judging the extent of involvement in osteoarthritis of the knee prior to surgical intervention. Radionuclide joint imaging is more sensitive than clinical or radiographic techniques in detecting early joint involvement but usually it must be supplemented by other techniques to establish a specific diagnosis.