History and radiographic findings associated with clinically suspected radial head subluxations

Objectives: To determine: I) physician practices regarding the use of radio graphs for radial head subluxations (RHS), 2 the prevalence of missed fract ures in children with a clinical diagnosis of RHS, 3) the relative risk of a fracture with a nonclassic history for mechanism of injury for RHS, and 4 ) radiographic findings associated with RHS that are difficult to reduce. Methods: This study began with a physician survey that addressed the integr ation of radiographs into the management of RHS, me subsequently conducted a prospective randomized trial with a consecutive sampling of children less than 6 rears of age who presented to one of 2 urban pediatric emergency de partments and 2 suburban pediatric urgent care centers with a clinical diag nosis of RHS, After informed consent was obtained, reduction was undertaken with a maximum. of four attempts (two by hyperpronation and two by supinat ion/flexion), 15 minutes apart. Failure to reduce the RHS resulted in the p rocurement of a radiograph of the elbow. Bt the conclusion of the study, al l radiographs were evaluated by a radiologist blinded to the diagnosis. Pat ients receiving radiographs were contacted 2 weeks after discharge for veri fication of the diagnosis. Results: Eighty-four percent of 224 physicians returned completed surveys, Fifty-six percent reported using radiographs for failed reduction attempts. Zn the second phase of the study, 136 patients were enrolled prospectively : 127 were reduced successfully and 9 patients failed attempts at reduction . Of the nine patients receiving radiographs: four had fractures (prevalenc e of 2.9% with 95% confidence interval (CI) = 0.8-7.4), two had no radiogra phic findings and normal function on follow up, and three had isolated post erior fat pads on radiograph and normal function an follow-up. The relative risk of a fracture in children with a nonclassic history defined as any me chanism other than "pull" was 1.200 (95% CI = 0.441-3.264); the relative ri sk was 1.886 (95% CI = 0.680-5.231) when defining a nonclassic history as a ny mechanism other than "pull" or "fall." Conclusions: 1) Physicians tend to order radiographs for elbow injuries the r initially perceive to be radial head subluxations when attempts at reduct ion fail. 2) In our study, fractures in children who presented with the cla ssic flexed elbow/pronated wrist position were Fare. 3) The relative risk o f a fracture in children with a nonclassic history for mechanism of injury was not significant, 4) tin isolated finding of a posterior fat pad in a ch ild with RHS that is difficult to reduce was not associated with a fracture in our small sample of children with radiographic findings.