Observation of the use of 99mTc-phosphate imaging in peripheral bone trauma.

The utility of 99mTc-phosphate imaging of fractured bones adjacent to joints soon after injury is examined. Joints usually respond to trauma by a generalized increased regional concentration of the radiopharmaceutical; but with careful attention to technique, a superimposed focal deposition due to the fractured bone can be seen. Fractures which were initially indefinite or which seemed normal at radiography were revealed as early as 7 hours after injury. In our experience, failure to show a focal concentration beyond 3 days excludes a fracture. However, a focal concentration need not necessarily represent a gross fracture; a ligamentous avulsion of a bone chip and/or periosteum could yield the same picture and not be disclosed by radiography. Radionuclide imaging of joint fractures is a useful adjunct to clinical assessment.