Determination of the vitality of the femoral head with 99mTc-Sn-pyrophosphate scintigraphy.

A series of 14 patients who for various reasons were scheduled for total hip replacement were investigated. 99mTc-Sn-pyrophosphate scintigraphy and tetracycline labelling of the bone structure was performed prior to surgery, and subsequently the femoral heads were submitted to histological evaluation on decalcified as well as non-decalcified slides. The evaluation of the scintigraphs was performed by a specialist in nuclear medicine and the histological slides were evaluated by a pathologist, in both cases without reference to the radiological findings or the clinical history. The scintigraphic evaluations of the vitality of the femoral head were in all cases verified by the histological examination, whereas the radiological findings in three cases failed to demonstrate that a femoral head necrosis actually was present. From this study it can be concluded that 99mTc-Sn-pyrophosphate scintigraphy is an excellent method of assessing bone vitality in the femoral head.