Bone marrow scintigraphy in the diagnosis of post-traumatic avascular necrosis of bone

A series of 19 patients, who were clinically suspected of developing avascular necrosis of bone following fracture, were entered into a pilot study comparing the use of bone marrow scintigraphy with conventional skeletal scintigraphy. Two-phase bone scintigraphy, using 600 MBq of 99Tcm-HMDP, and perfusion and late-phase nanocolloid scintigraphy, using 370 MBq of 99Tcm-nanocolloid, were performed on each patient. In both methods, photon deficiency at the site of interest was taken to indicate avascularity. The perfusion phase of both methods was found to be unhelpful. Agreement between methods was obtained in 18 patients (95%). Six patients had abnormal nanocolloid scans, one of which was normal on the conventional bone scintigram. The remaining 13 patients had no evidence to suggest avascularity in either method. Three of the patients with abnormal scans have had hip replacement surgery following which avascularity of the femoral head was confirmed. 99Tcm-nanocolloid scintigraphy is thus shown to be a very sensitive method of demonstrating avascularity of bone following trauma.