Tetracycline labeling of the femoral head following acute intracapsular fracture of the femoral neck.

The purpose of this study was to assess the utility of tetracycline hydrochloride (HCl) labeling of the femoral head following acute intracapsular fracture of the femoral neck to indirectly assess femoral head viability and vascularity. A standard labeling (1.5-3.0 g) and fixative protocol (70% ethanol) was used. The initial tetracycline dose was given in the emergency room. The time from last dose to bone sampling in the operating room ranged from six to 36 hours (average, 21.2 hours). There was no evidence of tetracycline deposition at the bone-osteoid interface in any of the femoral head specimens or the ipsilateral extracapsular greater trochanter control specimens. Sources of labeling failure are multifactorial: problems with label delivery to the patient, in vivo deposition of the label, and the fixation protocol.