Background: The use of radiography in evaluating inversion ankle injuries remains high despite several studies suggesting that x-ray examination should be limited to patients meeting certain clinical criteria. These studies were all done in emergency departments. The present study examined detection of ankle fractures by clinical evaluation alone in private family practice offices.
Methods: Twelve physicians in three family practice offices participated. Check-off forms were developed to record clinical data. The physicians all attended a session to standardize terminology. The physicians then evaluated 94 consecutive patients with inversion ankle injuries.
Results: Eight fractures were detected by radiography, five of which had not been suspected on clinical examination (5.9% false-negative rate). Only one fracture required treatment different from that for a sprain. Tenderness on the dorsum of the foot, impaired weight-bearing ability, recentness of injury (less than 12 hours earlier), and presence of additional injuries were significantly associated with a fracture. Unlike several previous studies, swelling was not associated with fractures. If radiography had been limited to patients presenting with inability to bear weight fully or tenderness on the dorsum of the foot, none of the fractures would have been missed, and the use of radiography would have been reduced from 90% to 61%.
Conclusions: The fracture rate in these family practice offices is lower than that reported in most emergency department studies. It is important that family physicians order radiographs judiciously rather than routinely for patients with inversion ankle injuries. The clinical criteria reported here are likely to reduce unnecessary ordering of radiographs and are compatible with recently published, prospectively validated rules for acute ankle injury in an emergency department setting.