CLINICAL-CRITERIA FOR USING RADIOGRAPHY FOR CHILDREN WITH ACUTE KNEE INJURIES

Objective: To evaluate clinical criteria for selective radiography for knee injuries in children. Design: Retrospective chart review. Settin g: Emergency department (ED) of a children's hospital. Participants: A ll patients evaluated by radiography for an isolated, acute knee injur y during 12 months. Patients were excluded for injuries: >1 week; isol ated to superficial:lacerations/abrasions; with prior knee surgery; be ing reassessed. Results: Two hundred fifty-four patients (60% male; 12 .7 years median age) were included. Twelve patients (4.7%) sustained a fracture. Evaluated criteria were point tenderness, inability to bear weight in the ED, and inability to flex the knee to 90 degrees, Point tenderness was not statistically associated with fracture, P = 0.7, I nability to bear weight in the ED (37% fracture rate, P = 0.001) and i nability to flex to 90 degrees (52% fracture rate, P < 0.001) were ass ociated with the presence of fracture, [GRAPHICS] Applying a rule comb ining nobearwt and noflex90 would decrease the number of x-rays by 73% , with no missed fractures. Conclusions: Point tenderness was not a go od predictor of knee fracture in children. Using the clinical criteria to select patients requiring knee radiography may greatly reduce the number of unnecessary x-rays.