First Aid/Temporary Immobilization of Limb Fractures With Bandages and Splints

The word coapt means to approximate, fit together, or fasten. Coaptation refers to the immobilization of a limb with the use of an external sling, bandage, splint, or cast. Some long bone fractures are best managed with bandages or splints for temporary “first aid” immobilization until definitive treatment via surgical fixation can be achieved; other fractures can be effectively managed with a splint or cast as the primary definitive treatment. In carefully selected instances, coaptation may be used as ancillary support for internal fixation of fractures. Coaptation for temporary first aid immobilization is discussed here; use of splinting/casting for definitive treatment of selected fractures will be the subject of a future article.

Indications for First Aid Immobilization

In cases of traumatic fracture or luxation, temporary limb immobilization improves patient comfort, controls regional soft tissue swelling, provides a protective covering for open wounds, and can prevent closed fractures from becoming open fractures via skin penetration by sharp fracture fragments. Most fractures distal to the elbow (front limb) or stifle (hindlimb) are best treated with temporary coaptation until definitive treatment can be performed. The coaptation must immobilize the joint above and below the fracture zone, as demonstrated by the purple bandage immobilizing a tibial diaphyseal fracture in FIGURE 1; otherwise it may only add detrimental weight to the distal limb while failing to immobilize the fracture, as demonstrated by the red bandage in this figure.

Figure 1. The coaptation should span the joint above and below the fracture. For temporary immobilization of tibial shaft fracture the purple bandage (right) would be appropriate, but the red bandage (left) would not.

Selected humerus/femur fractures or elbow luxations may benefit from temporary immobilization in a spica splint if a protracted delay until definitive treatment or lengthy patient travel is required, although most can be well managed with liberal use of analgesics and strict cage rest until surgery is performed. It is important that all wounds be treated according to the principles of open wound management as a prerequisite to temporary limb immobilization.

Temporary First Aid Splint Versus Robert Jones Bandage

The Robert Jones bandage (RJB) is a highly versatile, soft, padded bandage for first aid management of many traumatic limb injuries, and the choice between its use and the use of temporary first aid splinting is largely one of personal preference and available supplies. The RJB does not require any splinting materials and is highly cost effective, but it does require the manual skill necessary to manage thick cotton rolls. Temporary first aid splints, on the other hand, use small rolls of cast padding that are easier to manage, but require various splint materials and the manual skill to manage them. The RJB is not suitable for treatment of fractures proximal to the elbow or stifle; application of a spica splint is necessary if temporary coaptation is deemed appropriate for these fracture locations.

Choice of Splinting Materials

In general, the choice of splint is between a premanufactured (“off the shelf”) plastic or metallic splint and a custom-molded splint. Custom-molded splints are generally preferred based on their superior ability to provide bony alignment and immobilization and to minimize focal sites of irritation, but premanufactured splints can be appropriately used for some temporary immobilization situations. While prefabricated splints may offer some convenience, a substantial inventory must be maintained to allow appropriate fitting to patients of all sizes and various limb contours (e.g., front, hind, right, left).

The most commonly used materials for custom molded splints are thermoplastics and fiberglass. Thermoplastic splints are sometimes sold in perforated or nonperforated solid sheets (Orthoplast; bsnmedical.com), but most are sold in the form of a thermoplastic-impregnated mesh (Vet-Lite; jorvet.com).

Thermoplastic Mesh

Thermoplastic splinting materials require the use of a hot water bath. Hot water from the faucet is insufficient to mold the material or make it self-adherent. The thermoplastic mesh is immersed in hot water (>160°F [71°C]) for 2 or 3 minutes before removal using forceps or tongs. It can then be cut, layered, and molded. Because the material is often hot during molding, the authors prefer to don 1 or 2 pairs of gloves for this step. The material should be worked well to promote adhesion between layers. If necessary, the splint can be reheated for further molding and layering. Several layers of mesh are required for most slab splint applications. The ability to cut and remold thermoplastic splints offers a potential cost efficiency since a single splint can often be remolded to the needs of several different patients over time.

Fiberglass Tape

Fiberglass casting tape is impregnated with polyurethane. Fiberglass splinting materials do not require the use of a hot water bath to activate the molding and hardening process. In fact, the rate of hardening is proportional to the water immersion temperature; room-temperature water is usually best to allow adequate time for splint molding before hardening. As with thermoplastic mesh, several layers of fiberglass casting tape are required for most slab splint applications, and the casting tape should be worked to promote adhesion between layers and to remove any wrinkles. Unlike thermoplastic mesh, once fiberglass has hardened it cannot be reheated for further molding. Hardened fiberglass material typically requires a cast cutter (or similar oscillating-type saw) to cut through multiple layers.

A recent mechanical comparison of thermoplastic and fiberglass splint materials showed that fiberglass produces the stiffer construct, but the relevance of this finding to the clinical first aid scenarios described in this article is likely nominal.¹

Additionally, aluminum rods of various diameters (according to patient size) or even tongue depressors (for the very smallest patients) are used in some first
aid applications.

Application Techniques

The following techniques have also been published in video format.^2,3

Robert Jones Bandage

Supplies needed for the RJB are listed in BOX 1. Sedation or general anesthesia may be required as dictated by factors such as patient mentation, comfort, and concurrent first aid procedures. Bandage/splint application is often performed immediately after radiography.

Step 1: Patient Position, Wound Care, and Tape Stirrups

Position the patient in lateral recumbency with the affected limb uppermost. Manage any open wounds with appropriate clipping, cleaning, lavage, debridement, and primary layer and secondary layer dressings as dictated by first aid wound healing principles. Apply 1-inch porous white tape strips to the medial and lateral limb surfaces from the carpus/tarsus, extending approximately twice this length distal to the digits. Fold over the distal ends of the tape stirrups to create nonadherent tape tabs; a tongue depressor may be placed between the strips of tape if desired (FIGURE 2).

Figure 2. Apply tape strips on the medial and lateral sides of the limb extending toward and past the toes, ending in folded-over tabs.

Step 2: Sizing the Bulky Cotton Roll

Unravel the roll of cotton and remove the paper. If the roll is too thick, the layer thickness can easily be separated into 2 half-thickness rolls (FIGURE 3). The 12-inch width is too wide for many patients and the roll can easily be torn longitudinally when unraveled or simply pulled apart (FIGURE 4).

Figure 3. Prep the cotton rolls by unrolling and adjusting to the desired thickness.

Figure 4. Cotton width can be adusted as well by tearing longitudinally.

Step 3: Applying the Bulky Cotton Roll

Have an assistant apply gentle traction to the limb via the tape stirrups. Hold the cotton roll as if holding a snail by its shell while wrapping the free end of the roll (representing the snail’s gooey body) snugly around the distal limb, starting at the nail beds of the central digits 3 and 4 (FIGURE 5). This way of holding the roll (in contrast to applying the roll with the “snail body” held upside down) allows for fine control of the tension of application. Apply the cotton roll with firm, even pressure, with approximately 50% overlap of each circumferential layer from the toes distally to mid-humerus or mid-femur proximally. There is little risk of getting this layer too tight, as it will typically tear if too much tension is applied.

Practical tip: The assistant applies countertorque on the stirrups at the level of the toes to avoid excessive rotation of the distal limb in the direction of the cotton roll application (FIGURE 5). If distal limb rotation occurs despite countertorque on the stirrups, successive layers can be applied in the opposite direction (i.e., alternating between clockwise and counterclockwise layer applications).

Figure 5. Begin wrapping the cotton roll at the toes and wrap upward, making sure there is adequate overlap and firm, even pressure. An assistant can apply countertorque.

Step 4: Applying the Roll Gauze Layer

Apply roll gauze to firmly compress the underlying cotton layer. The gauze is, again, held as if holding a snail by its shell and is snugly applied from distal to proximal with ~50% overlap of each successive layer (FIGURE 6). It is sometimes preferable to use a criss-crossing “dovetail” pattern to maintain uniform tension and diameter throughout the bandage (FIGURE 7). Unlike with other bandages, compression of the thick underlying cotton layer requires that the roll gauze layer be applied with firm, snug tension in the roll.

Figure 6. Apply the roll gauze with firm pressure over the cotton wrap, leaving enough space at the ends for visible cotton.

Figure 7. A uniform tension and diameter are achieved when using a criss-crossing dovetail pattern application of roll gauze.

Since firm pressure is required to compress the underlying layer, countertorque will need to be applied to the limb segment with the operator’s opposite hand or by an assistant. This layer should extend to the proximal and distal margins of the underlying cotton roll but should not be in contact with the skin. There should be no constricting bands of gauze within this layer.

Step 5: Securing the Tape Stirrups

Separate the tape stirrups and twist each one so that the adhesive surface is against the gauze wrap. The middle 2 toes should be visible through the end of the bandage (FIGURE 8).

Figure 8. Take the tape tabs and pull over the cotton, securing the gauze wrap. The patient’s middle 2 toes should be visible.

Step 6: Outer (Protective) Layer

Short strips of elastic adhesive tape can be used to reinforce the distal end of the bandage. A self-adherent elastic wrap is then applied from distal to proximal using care to have ~50% overlap of each successive layer. The tension within this outer layer is regulated to generate the desired degree of compression on the underlying bandage layers; unlike with less bulky bandages, moderate tension is sometimes applied to the layer.

Rule of thumb: A properly applied RJB should feel firm (not soft and pliable) and should “thump” like a ripe watermelon. Two-inch adhesive elastic tape can be used to reinforce the upper and lower margins of the bandage if desired. Even though there is no splint material in an RJB, the compression of the thick, bulky cotton roll provides adequate immobilization to foster patient comfort when properly applied (FIGURE 9).

Figure 9. To help with the patient’s comfort, use elastic adhesive tape for reinforcement, apply with moderate tension, and overlap each successive layer.

Temporary Slab Splint

In contrast to a circumferential cylindrical cast, a slab splint is a multilayered, custom-molded splint typically applied on the lateral, cranial, or caudal surface of the limb. Supplies needed for the splint are listed in BOX 2.

Step 1: Patient Position, Wound Care, and Tape Stirrups

Follow the Step 1 instructions for the RJB.

Step 2: Applying the Padding Layer

Apply cotton or synthetic (polypropylene) cast padding snugly from distal to proximal with an ~50% overlap of successive layers, similar to that described for the RJB. The most common error with this layer is applying it too loosely; most cast padding materials will tear if they are pulled too tightly. As a general guide, some products (Specialist Cast Padding; bsnmedical.com) have a micropleated texture (FIGURE 10) and the material should be tensioned until the pleated structure is flattened (FIGURE 11). Regardless of the material used, care should be used to avoid getting wrinkles in this layer (FIGURE 12). Take care to provide adequate padding over bony prominences, although this is more critical when splints or casts are used for longer-term primary (definitive) treatment of long bone fractures.

Figure 10. Some brands of cast padding have a pleated structure that can guide the proper tension of application.

Figure 11. Pull the pleated cast padding taut enough to flatten the micropleated texture.

Figure 12. There should never be wrinkles in this layer, regardless of material and type.

Step 3: Applying the Roll Gauze Layer

Apply roll gauze snugly from distal to proximal, taking care to have ~50% overlap of each circumferential wrap (a dovetail pattern is preferred by some, especially in areas of abrupt directional change such as around the tarsus or elbow). Apply even tension to the gauze roll and take care not to pull this layer too tightly, as there is less cotton padding underneath than with an RJB. This layer should extend to the proximal and distal margins of the underlying cotton roll but should not be in contact with the skin. There should be no constricting bands of gauze within this layer (FIGURE 13).

Figure 13. Apply roll gauze with slightly less pressure than on an RJB since there is less padding.

Step 4: Molding the Splint With Fiberglass Casting Tape

Adherence of the splint material to the underlying roll gauze layer can be prevented by temporarily placing a layer of plastic kitchen wrap between the splint and the gauze layer, but this layer will need to be removed after splint hardening because it traps moisture in the bandage. Alternatively, a layer of self-adhesive elastic wrap (e.g., Vetrap; 3m.com) can be used; since this material breathes, it does not require removal after hardening of the splint.

Anyone handling the fiberglass casting tape should don examination gloves to prevent contact of the resin with their skin. Activate the fiberglass casting tape by opening the package and fully submerging the roll in room-temperature water. Squeeze the roll firmly to expel excess water. Unravel the roll to a sufficient length to span from the toes to the proximal margin of the bandaged segment (spanning the joint above and below the fracture). It is advisable to slightly overestimate the length needed, as some shrinkage occurs during setting; excessive splint length can always be cut as needed, but length cannot be added after the fact.

Unravel the roll further to allow for successive layers of identical length (FIGURE 14). Overlap the splinting material sufficiently to provide adequate support for the fractured limb according to its inherent instability, patient size, and activity level. Usually, 4 to 6 layers are needed. The casting tape may then be lifted from the bandage so it can be worked to eliminate folds and wrinkles and to ensure adhesive bonding of the resin between successive layers (FIGURE 15).

Figure 14. Apply the casting tape along the length of the underlying bandage, overlapping 4 to 6 layers.

Figure 15. Remove the layers and pull to get rid of wrinkles.

Before fiberglass hardening, trim any sharp edges or excessive splint length with heavy-duty bandage scissors (FIGURE 16). Apply the layered splint to the cranial, lateral, or caudal surface of the limb as dictated by the bony prominences, underlying wounds, stabilization needs, and personal preference. Gentle application of a gauze layer over the top of the casting tape can ensure a nice-fitting custom mold while securing the splint to the underlying bandage (FIGURE 17).

Figure 16. Trim the edges before the fiberglass hardens.

Figure 17. Lightly applying roll gauze over the mold ensures a custom fit.

Step 5: Securing the Stirrups

Securing the stirrups to the outside of the bandage and splint helps prevent them from slipping distally on the limb. Separate the tape stirrups and twist each one so that the adhesive surface is against the gauze wrap. The middle 2 toes (digits 3 and 4) should be visible through the end of the bandage.

Step 6: Outer (Protective) Layer

Apply strips of adherent elastic tape (Elastikon; jnjsportsmed.com) around the distal and proximal margins of the bandage for reinforcement of these vulnerable regions. Apply self-adherent elastic wrap from distal to proximal with a 50% overlap. Unlike with an RJB, take care to partially unroll these elastic layers from the roll before applying them, almost tension-free, around the bandage to avoid constricting blood and lymphatic flow in the limb (FIGURE 18). The central 2 digits should be visible and palpable through the distal end of the bandage to allow detection of swelling (FIGURE 19).

Figure 18. Apply elastic wrap lightly so as not to impede blood flow.

Figure 19. The middle 2 toes should be visible to allow for detection of swelling.

Spica Splint

This splint is the least commonly used of the bandages and splints described in this article, but it may be indicated when definitive treatment for elbow luxation or femur/humerus fracture is delayed or requires lengthy patient transport. Application of the spica splint is essentially just an extension of the slab splinting process to include the patient’s torso (for a humerus fracture or elbow luxation) or pelvis (for a femur fracture), so only the additional steps are described below.

Steps 2 and 3: Padding and Gauze Roll Layers

Extend each of these layers around the patient’s torso or pelvis several times, alternating cranial and caudal to the affected limb. When applied to the front limb, this wrap remains caudal to the contralateral front limb (FIGURE 20); when applied to the hindlimb, this wrap remains cranial to the contralateral hindlimb. Take care to wrap cranial to the prepuce when applying the spica splint to the pelvic limb of male dogs. For both front limbs and hindlimbs, wider cast padding and gauze rolls than were used on the limb itself can be advantageous for this portion of the bandage.

Figure 20. For a spica splint, extend the padding and roll gauze up and over the torso or pelvis.

Step 4: Molding and Padding

A plastic trash bag can temporarily be laid on the soft padded bandage to prevent adherence of the splint to the underlying layers during the molding process. Activate the splinting material in water, and size and mold layers together as with any splint. Lay the melded layers of splinting material on the patient with splint material extending from the toes distally to slightly across the patient’s dorsal midline proximally. Manually mold the splint to the contours of the patient’s limb and trunk (FIGURE 21). Once the splinting material has set, temporarily remove it from the patient and trim any sharp edges and/or excessive length. The upper portions of the splint itself can be padded by circumferentially wrapping it with 2 or 3 layers of cast padding and self-adhesive elastic wrap (FIGURE 22).

Figure 21. Mold the splinting material from the toes to the top of the back, using a trash bag to ensure it doesn’t stick prematurely.

Figure 22. The upper portions of the splint material can be padded with cotton and elastic wrap.

Step 5: Securing the Splint

Use roll gauze to secure the splint to the underlying bandage (FIGURE 23). Again, wider rolls may prove helpful for securing the upper portions of the spica splint to the patient’s trunk.

Figure 23. Apply wide rolls of gauze over the splint and elastic wrap.

Step 7: Applying the Outer (Protective) Layer

Be especially careful with this elastic layer on spica splints applied to the front limb, as compression of the patient’s thorax can compromise respiratory function (FIGURE 24). Since most of these patients are heavily sedated or anesthetized during splint application and some have preexisting pulmonary trauma, their ventilation must be closely monitored after spica splint application. If necessary, the outer elastic wrap can be cut and reapplied more loosely.

Figure 24. Wrap the whole bandage with elastic wrap, making sure to keep light compression so as not to impede breathing.

Aftercare

After placement of any bandage or splint, observe the patient closely for toe swelling, bandage loosening, soiling, or other problems. The bandage can be partially protected from water and soiling by covering it with a sleeve harvested from a clean, disposable surgical gown. A purpose-specific protective boot (e.g., Medipaw; medivetproducts.com) should be used when the patient has to walk on wet surfaces (e.g., wet grass, snow, kennel runs) for elimination purposes. If the patient is to be discharged from the hospital to seek care from another provider, a tape strip can be applied to the outside of the bandage that states, “This bandage/splint is NOT suitable for definitive treatment of this fracture. Seek further veterinary care no later than DATE LISTED HERE.”