Above and below-the-elbow plaster casts for distal forearm fractures in children. A randomized controlled trial.

BACKGROUND: Closed fractures of the distal third of the forearm are the most common fractures of childhood, but the method of immobilization after closed reduction is controversial. This study was undertaken to determine whether below-the-elbow casts are as effective as above-the-elbow casts in immobilizing these types of fractures and to identify patient and treatment considerations that are related to loss of reduction.

METHODS: We designed a blinded, randomized, controlled trial. The criteria for reduction and remanipulation were set a priori. The primary outcome measure was fracture immobilization as reflected by reangulation in the cast and by the need for remanipulation. Exploratory analysis with use of stepwise logistic regression analysis was undertaken to search for factors predictive of loss of reduction.

RESULTS: A total of 102 children were enrolled in the study and were allocated to two groups: the above-the-elbow cast group (fifty-six children) and the below-the-elbow cast group (forty-six children). The mean age was 8.6 years, and sixty-one patients were boys. The groups did not differ with respect to the initial fracture angulation, postreduction angulation, reangulation during cast immobilization, and angulation of the fracture at the time of cast removal. In the above-the-elbow cast group, twenty-three (42%) of fifty-five children with adequate radiographs met the criteria for remanipulation compared with fourteen (31%) of forty-five children with adequate radiographs in the below-the-elbow cast group (p = 0.27); only four of these thirty-seven children actually underwent remanipulation. Children with fractures of both the radius and ulna (p = 0.01) and those with residual angulation after reduction (p = 0.0001) were at the highest risk of meeting the criteria for remanipulation. The rates of complications related to the cast did not differ between the groups.

CONCLUSIONS: Below-the-elbow casts perform as well as above-the-elbow casts in maintaining reduction of fractures in the distal third of the forearm in children, and the complication rates are similar. Factors that are associated with a higher risk of loss of reduction include combined radial and ulnar fractures and residual angulation of the fracture after the initial reduction.