Comparison of two different ways to apply a circular plaster cast for distal radius fractures: biomechanical study

INTRODUCTION: Although conservative treatment with circular plaster cast is the most commonly used method in distal radius fractures, the best method to apply it remains unclear. MATERIAL AND METHODS: Two frequently used configurations of circular plaster cast (with and without a splint) were selected to compare. Group C was applied only with circular bandages (three units) and group S with a splint (one unit) and over it, a circular bandage (two units). Both configurations had the same weight. Five prototypes of each group were built and mechanically tested. Three-point flexural tensile strength and maximum deflection were measured and compared. RESULTS: The previously splinted prototypes (group S) obtained higher tensile strength with the same weight (p < 0.05). DISCUSSION: No other study regarding strength and configuration of circular casts for distal radius fractures immobilization has been previously published, leading to a high variability in construction among orthopedic surgeons. Data confirms that applying a splint before circular bandage offers more mechanical resistance to the cast in flexion, with the same weight. CONCLUSION: Applying a splint before circular bandage for plaster casts used for distal radius fractures make them more resistant to usual forces.