Plaster cast types: what to know

Plaster of Paris is shaped around the limb and can be useful when a careful mould is needed. It may be selected when swelling is expected because the team can create a supportive fit and reassess it. Fibreglass is lighter and forms a firm outer shell, but it still needs protection from impact, heat, and moisture unless your clinician has specifically provided a waterproof setup.

A full cast surrounds the limb, while a splint leaves room for swelling. A cast may be used for an ankle fracture or distal radius fracture, and the design changes with the body part and fracture pattern. Material alone does not determine healing; alignment, follow-up, and safe activity also matter.

Keep the cast clean, dry, and intact. Elevate the limb when it is swollen, move free fingers or toes as instructed, and avoid placing anything inside the cast. Do not cut or alter the edges. Follow the activity limits you were given, because a cast can protect the bone while still being damaged by falls, pressure, or careless loading. Physiotherapy may be introduced after removal to address stiffness, strength, balance, or movement.

Seek prompt advice for worsening pain, a cast that feels too tight or loose, numbness, tingling, unusual coldness, colour change, or inability to move the exposed digits. Get medical help for a cracked, wet, foul-smelling, or damaged cast, skin breakdown, fever, or drainage. These signs can indicate pressure, skin trouble, infection, or loss of support.

Ask why a particular material or splint was chosen, whether the cast can get wet, how to protect it during sleep and bathing, when it will be checked, and which activities are restricted. Clarify what symptoms require same-day review.