The initial approach to casting and splinting involves a thorough assessment of the injury for proper diagnosis to include an exam above and below the injured area.

The purpose of splinting and casting is to immobilize, protect, aid in healing, and decrease pain.

Immobilization offers three benefits: prevention of loss of position, protection of adjacent structures, and pain relief.

Conditions that benefit from immobilization include fractures, sprains, severe soft tissue injuries, reduced joint dislocations, inflammatory conditions, deep lacerations across joints, and tendon lacerations.

Complications can occur regardless of how long the device is used (13).

Consideration for casting versus splinting requires assessment of the stage and severity of the injury, the potential for instability, the risk of complications, and the patient’s functional requirements.

Splinting is more commonly used in the primary care setting (6).

If an injury is associated with significant swelling or more swelling is anticipated, initial splinting followed by casting for definitive treatment is recommended.

Maximal immobilization cannot be obtained unless the joints above and below the fracture are immobilized, which is required for most unstable or potentially unstable fractures.

Splinting offers many advantages over casting, including easier application and removal and decreased pressure-related complications because they are noncircumferential.

Disadvantages include decreased patient compliance and increased motion at the injury site.

Splints may be used in the acute setting and later replaced by a cast for definitive treatment of unstable of potentially unstable fractures (6).

Casting is the mainstay of treatment for most fractures (6).

Casts provide superior immobilization and are reserved for complex and/or definitive fracture management (13).

They require more skill and time for application.

Plaster is traditionally preferred for splints because it is pliable and has a longer setting time than fiberglass and produces less heat, which avoids burns and patient discomfort (15).

Fiberglass is less messy and lighter than plaster and is typically used for nondisplaced fractures and severe soft tissue injuries.

Casts set slower in colder water than warm water (3).

Regardless of material used, water temperature is the most important variable. Heat is inversely proportional to the setting time and directly proportional to the number of layers of casting material used (4,5).

Plaster is cheaper and has a longer shelf life, while fiberglass is more durable and lighter.

Fiberglass is generally preferred for casting by providers who have more experience casting and who treat larger numbers of fractures.

Other materials and equipment include: adhesive tape for splints, bandage scissors, casting gloves for fiberglass, elastic bandage for splints, padding, sheets/underpads, and stockinette.

The involved extremity should be assessed, and documentation of skin lesions, neurovascular status, soft tissue injury, and bony structures should be performed. Neurovascular status should be rechecked following immobilization by cast or splint.

A stockinette is measured and applied to cover the area of injury and extend 10 cm beyond each end or the intended splint site. Excess is folded back to form a smooth edge once the splint or cast material has been applied. It is important to make sure the stockinette is not too tight and wrinkles are smoothed.

Layers of padding are placed over the stockinette to prevent maceration of skin and accommodate swelling.

Padding is wrapped circumferentially, with each new layer overlapping 50% of the previous layer. It should be two to three layers thick and extend 2-3 cm beyond the edge of the splint.

Extra padding is placed between digits and over bony prominences. Too much padding can compromise support of the splint.

Joints are always placed in proper position of function.

Add 1-2 cm of splinting to each end of the splint to allow for shrinkage. Ultimately, the splint should be slightly shorter than the padding.

The thickness or the splint depends on patient size, extremity involved, and desired strength. On average, an adult upper extremity should be splinted with 6-10 sheets; lower extremities require 12-15 sheets (4,5).