Avascular Necrosis Associated with Nailing of Femoral Neck Fracture: Two Cases Examined Pre- and Postoperatively by Tetracycline and Radionuclide Tracer Techniques

Abstract
Two patients with femoral neck fractures, 1 displaced and 1 undisplaced, are presented. Preoperative intravital staining with tetracycline and Tc-MDP [Tc-methylene dyphosphonate] scintimetry both showed intact femoral head circulation while Tc-MDP-scintimetry 1 wk after operation showed pronounced circulatory deficiency. Sr85-scintimetry performed at the same time was inconclusive. Segmental collapse was observed radiographically, 8 and 12 mo. postoperatively. The major vascular injury resulting in avascularity most probably occurred during the procedure of osteosynthesis, and Tc-MDP-scintimetry was found suitable for early postoperative recognition of avascular necrosis in both fractures.