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

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.

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.

The previously splinted prototypes (group S) obtained higher tensile strength with the same weight (p < 0.05).

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.

Applying a splint before circular bandage for plaster casts used for distal radius fractures make them more resistant to usual forces.