Based on the results of a pilot study indicating the potential value of ultrasound (US) as a diagnostic tool for the early assessment of fracture healing and the related need for secondary operative procedures in patients treated by statically locked intramedullary (IM) nailing without reaming, a protocol was established for a larger scale prospective trial. The purpose of this study was to evaluate the outcome of this follow-up trial.Design/Methods:
All skeletally mature patients admitted to the Henry Ford Hospital (Detroit, Michigan) from January 1993 to August 1994 who had sustained an acute fracture of the tibial shaft and who were treated by statically locked IM nailing, without reaming, were candidates for study. Forty-seven patients with fifty fractures that could be evaluated by US were included. The adopted determinants for fracture healing were complete disappearance of the IM nail on US examination performed at six weeks postoperatively, or progressive disappearance of the nail noted between the initial six-week study and a second nine-week US examination, both in conjunction with periosteal callus formation. Radiographs were obtained to monitor maintenance of reduction and to further evaluate fracture healing.Results:
Of thirty-eight fractures with a positive US (thirty-two at six weeks, six at nine weeks), thirty-seven healed uneventfully, a positive predictive value of 97 percent. Radiographic fracture healing was not evident until, on average, nineteen weeks after injury. The single false-positive fracture progressed to nonunion. Of the twelve fractures with negative US studies, ten underwent secondary procedures (nine dynamization, one bone graft), with four progressing to nonunion. Two patients refused secondary surgery; screw failure occurred in both. Otherwise, there were no hardware failures in this series.Conclusions:
The results of this study indicate that US may provide important prognostic information concerning fracture healing after unreamed tibial nailing, upon which subsequent treatment can be based.