Patient Preparation

Carefully inspect and examine the involved extremity before splinting, and clearly document the presence of all skin lesions and soft tissue injuries. When open fractures or joints are to be immobilized, cover the soft-tissue defect with saline-moistened sterile gauze prior to splint application.

Padding

In the setting of severe trauma, when rapid temporary immobilization is required, it is easier and faster to place two or three layers of cast padding (the same diameter or slightly wider than the plaster splint) over the wet plaster rather than wrapping the cast past padding around the extremity. The cast padding should extend 2.5 to 5.0 cm beyond the ends of the splint so that it can be folded back over the splint to help create smooth, well-padded edges. When possible, place extra padding over areas of bony prominence, such as the radial condyle or the malleoli.

Plaster Preparation

The choice of plaster setting time depends on the nature of the injury and the expertise of the clinician. Use fast- or extra-fast-setting plaster when rapid hardening is desired to help maintain alignment of an acutely reduced fracture.

The ideal length and width of plaster depend on the body part to be splinted. The best way to estimate length is to lay the dry splint next to the area to be splinted. It is best to use a generous length because wet plaster shrinks slightly from its dry length. Also, if the wet splint is too long, the ends can be folded back easily. The plaster width varies according to the type of splint being made and the body part that is injured, but generally, it should be slightly greater than the diameter of the limb to be splinted. Specific recommendations regarding splint length and width are discussed in the sections describing individual splints.

The thickness of a splint depends on the size of the patient, the extremity that is injured, and the desired strength of the final product. In general, it is best to use the minimum number of layers necessary to achieve adequate strength. Thicker splints are heavier and more uncomfortable. It is also important to note that plaster thickness is a major determinant of the amount of heat given off during the setting process. More than 12 sheets of plaster create an increased risk of significant burns, especially when using extra-fast-drying plaster or using dipping water with a temperature greater than 24°C. For an average-sized adult, splint upper extremities with 8 sheets of plaster and lower extremities with 12 to 15 sheets. This layering usually gives the strength necessary for adequate immobilization while reducing the patient’s discomfort and the risk of significant burns.

Splint Application

Completely submerge the dry splint in a bucket filled with fresh water around 24°C until the bubbling stops. Remove the splint and gently squeeze out excess water until the plaster has a wet and sloppy consistency. Place the splint on a hard table or countertop (a protective covering is recommended to prevent water or plaster damage) and smooth out the splint (with gloved hands) to remove any wrinkles and ensure uniform lamination of all layers. Lamination helps increase the final strength of the splint. Lay the previously measured cast padding over the splint (the cast padding should extend 2.5–5.0 cm beyond the ends of the splint) and place the padded split over the extremity, padded-side down (against the skin). An assistant may be required to hold the splint in place during positioning. Once the splint has been properly positioned over the extremity, fold back the end of the cast padding to create smooth, well-padded ends and secure the splint with an appropriately sized elastic bandage by wrapping in a distal-to-proximal direction. Finally, place the extremity in the desired position and mold the wet plaster to the contour of the extremity with only the palms of the hand. Finger indentations may cause ridges, which can produce pressure points.

After Care

Following splint application, elevate the extremity (if possible) to reduce swelling and frequently check the injured extremity for adequate perfusion. Extremity color, temperature, pulses, and capillary refill should be reevaluated every 15 to 30 minutes and the results documented in the medical record.

Long Arm Splints

Long Arm Posterior Splint

(Figure 24.1 A,B)

Figure 24.1 A,B Long arm posterior splint. Extend the splint from the posterior aspect of the humerus to the elbow and then along the ulnar aspect of the forearm to the distal metacarpals. Flex the elbow to 90 degrees, maintain the forearm in the neutral (thumb-up) position, and place the wrist in a neutral or slightly extended (10–20 degree) position (A). Long arm anterior splint. An anterior splint that mirrors the posterior splint may be used to increase stability and prevent supination and pronation. An anterior splint is never used alone (B).

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  Indications. Use a long arm posterior splint to immobilize injuries to the elbow and proximal end of the forearm. It completely eliminates flexion and extension of the elbow but does not entirely prevent pronation and supination of the forearm. Therefore, it is not recommended for immobilization of complex or unstable distal forearm fractures unless used in conjunction with a long arm anterior splint (see later in this section).

  
  
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  Construction. Construct a long arm posterior splint with 8 to 10 layers of 4- or 6-inch-wide plaster. Start the splint on the posterior aspect of the proximal end of the arm. Extend it down the arm to the elbow and then along the ulnar aspect of the forearm and hand to the level of the metacarpophalangeal (MCP) joints. Cut a small notch on each side of the splint at the elbow to allow the plaster to bend smoothly when the elbow is flexed to 90 degrees.

  
  
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  Application. Pad the wet splint as described previously. Place extra padding over the olecranon to prevent pressure injury. Position the arm with the elbow flexed to 90 degrees, the forearm neutral (thumb upward), and the wrist neutral or slightly extended (10 to 20 degrees). Ask an assistant to hold the wet splint in place, particularly when applying both a posterior and an anterior splint. Once the splint has been properly positioned, fold the sides of the splint up to create a gutter configuration. Next, fold the ends of the cast padding back and secure the splint in place with 2-, 3-, or 4-inch elastic bandages. Once secure, carefully mold the plaster around the extremity with the palms of the hand.

Long Arm Anterior Splint

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  Indications. A long arm anterior splint is never used alone but, rather, as an adjunct to a long arm posterior splint to improve immobilization by increasing stability and preventing pronation and supination of the forearm.

  
  
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  Construction. Construct a long arm anterior splint in the same manner as described for a long arm posterior splint. It mirrors the posterior splint by running down the anterior aspect of the arm to the antecubital fossa, where it continues along the radial aspect of the forearm to the distal end of the radius.

  
  
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  Application. When using both an anterior and a posterior long arm splint, have an assistant available to hold the wet splint in place. Place the padded anterior splint first and then position the posterior splint. Once both splints have been properly positioned, fold the sides of the splint up to create a gutter configuration. Next, fold the ends of the cast padding back and secure the splint in place with 2-, 3-, or 4-inch elastic bandages. Once secure, carefully mold the plaster around the extremity with the palms of the hand.

Double Sugar-Tong Splint

(Figure 24.2)

Figure 24.2 Double sugar-tong splint. Apply the forearm portion of the double sugar-tong splint first. Begin the splint at the metacarpal heads on the dorsum of the hand, and then extend it along the dorsal surface of the forearm and around the elbow. Continue along the volar surface of the forearm and stop at the level of the metacarpophalangeal joints. Begin the arm portion on the medial aspect of the proximal part of the arm, and then run it down over the forearm splint and around the elbow. Continue up the lateral aspect of the arm (once again going over the forearm splint) until it reaches the starting point. Keep the elbow flexed at 90 degrees, the forearm in the neutral (thumb-up) position, and the wrist in a neutral or slightly extended (10–20 degree) position.

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  Indications. A double sugar-tong splint can be used as an alternative to a long arm anterior and posterior splint to immobilize injuries to the elbow and forearm when prevention of pronation and supination of the forearm is desired.

  
  
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  Construction. The splint consists of two separate pieces of plaster, a forearm splint and an arm splint. Construct each piece with eight layers of 3- or 4-inch plaster. The forearm portion of the splint runs from the metacarpal heads on the dorsum of the hand along the dorsal surface of the forearm around the elbow. It continues along the volar surface of the forearm to the palm of the hand and stops at the level of the MCP joints. The arm portion of the splint begins on the anterior aspect of the proximal end of the humerus. It runs down the arm over the forearm splint and around the elbow. It then continues up the posterior aspect of the arm until it reaches the starting point.

  
  
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  Application. Pad both splints as described previously. Use a 2-, 3-, or 4-inch elastic bandages to first secure the padded forearm splint starting at the hand. Once the forearm splint is secured in place, secure the arm portion of the splint beginning at its proximal end.