Moisture trapped within an orthopedic cast creates a conducive environment for several undesirable outcomes. The dampness softens the cast material, typically plaster or fiberglass, compromising its structural integrity. This loss of rigidity diminishes the cast’s ability to properly immobilize the injured limb, potentially hindering the healing process. For example, a wet plaster cast loses its form, leading to inadequate support for a fractured bone.
Maintaining a dry cast is crucial for preventing skin irritation and infection. A damp environment against the skin promotes the growth of bacteria and fungi. This can lead to maceration, a softening and breakdown of the skin, making it susceptible to abrasions, pressure sores, and infections. Historically, preventing this was a significant challenge with plaster casts, necessitating frequent cast changes. Modern fiberglass casts offer some improved water resistance, but complete submersion remains problematic.