Foot and pastern bandages

Wounds to the foot are usually the result of penetrating objects or of the foot becoming caught between two surfaces. Bandages are used to cover wounds on the sole of the hoof, the coronary band or the pastern. If there is a large defect in the sole, initial bandaging used during the acute phase of healing may be followed by the long‐term use of a specialized shoe, such as one with a removable plate covering the sole. If there is a defect involving the hoof wall, the hoof wall surrounding the wound is trimmed slightly shorter so that the shoe contacts the wall of the hoof, as normal, except at the affected area. A foot cast and/or a specialized shoe is necessary when a substantial portion of the hoof wall has been lost because it helps provide long‐term stability to the rest of the foot during the lengthy healing and regrowth of the horn.

Wounds of the sole, hoof, or pastern first receive generic cleansing and debridement, followed by primary closure, if warranted. A dressing suitable to the state of the wound is then applied (Figure 7.1a,b), followed by a secondary layer of cotton. For wounds on the sole, a large square of cotton can be placed on the bottom of the foot and folded up over the wall of the hoof and the coronary band then attached with elastic, self‐adhesive material (Figure 7.1c,d). A square patch of duct tape placed on the bottom of the foot, over the square of cotton, prevents wicking of moisture from the environment (Figure 7.1e). Finally, elastic, adhesive tape is lightly applied, circumferentially, to the top of the bandage and the surrounding skin, to prevent foreign material from migrating under the bandage (Figure 7.1f,g).

Pastern wounds involving the coronary band or heel bulb regions are bandaged in a manner similar to those on the hoof except that the bandage extends proximad to cover the wound in the pastern region. Most of these wounds are best managed with a phalangeal (foot/pastern) cast, discussed later. Lacerations of the mid and proximal pastern region may be managed by bandaging the region without including the bottom of the foot. In this case, elastic adhesive tape is used to attach the distal extremity of the bandage to the hoof wall (Figure 7.2).

Distal limb bandages (extending from the ground to the carpus or tarsus)

Practitioners are usually comfortable applying a bandage to the distal aspect of the limb of horses because this is a commonly traumatized area in their equine patients^8,9 and because bandages conform more readily to the metacarpus/metatarsus or fetlock than to the foot. The primary layer of the bandage (dressing) must suit the nature of the wound and is usually held in place with conforming gauze (Figure 7.3a). The thicker part of the secondary layer, consisting of cotton, is then applied (Figure 7.3b) and held in place with the tertiary layer, commonly elastic, self‐adhesive wrap such as Vetrap™ (Figure 7.3c). This tertiary layer must be applied evenly, distad to proximad, leaving a small border of the secondary layer exposed at either extremity to avoid applying pressure directly to the skin. These borders are then covered loosely by an elastic, adhesive tape, such as Elastikon®, that overlaps onto the skin to prevent the entry of foreign material under the bandage (Figure 7.3d). Horsemen are commonly taught to wrap the limb in such a way that the bandage material passes from outside to inside across the palmar/plantar surface of the limb: left limbs are wrapped counter‐clockwise, and right limbs are wrapped clockwise.

Carpal and tarsal bandages

Carpal and tarsal bandages resemble the bandages applied to wounds on the distal aspect of the limb, apart from two main considerations: they are more challenging to apply and maintain and they have a greater potential of causing pressure sores over areas with little soft‐tissue coverage (e.g., the accessory carpal bone in the forelimb and the point of the hock in the hindlimb). Some measures can help protect against the development of cast sores related to bandages on the carpus or tarsus. For the carpal area, the conforming gauze used to secure the wound dressing can be wrapped in a figure‐of‐eight pattern around the carpus (Figure 7.4a), thereby relieving some pressure on the accessory carpal bone and simultaneously filling in the relative depression surrounding it. Thus, when the main part of the secondary layer (i.e., the cotton pad) is applied (Figure 7.4b), pressure is distributed evenly to the palmar surface of the carpus rather than to a focal point (accessory carpal bone). Alternatively, the layers can be applied as usual and then a small “releasing” incision can be made in the tertiary and secondary layers, directly over the accessory carpal bone, to relieve pressure at this area (Figure 7.4c–f). Another method of preventing excessive pressure on the accessory carpal bone is to create a donut of conforming gauze or rolled up stockinette and positioning it so that the hole is over the accessory carpal bone. This can be placed between the conforming gauze holding the primary layer in place and the secondary layer of cotton padding. This effectively prevents pressure on the bone when correctly positioned but, since the donut may slip, increased rather than decreased pressure may arise at a point under the bandage. Ultimately, the method used to reduce pressure on the accessory carpal bone when bandaging this area should be tailored to the materials available and the behavior of the patient.

The conformation of the hock and the combination of forces generated by the reciprocal apparatus impose some important considerations when applying a bandage to this region. Horses are reluctant to accept restricted movement of this area and frequently disrupt the bandage by hyper‐flexing the hock. Placing the conforming gauze in a figure‐of‐eight pattern around the point of the hock (calcaneal tuberosity) not only relieves pressure but is also useful in preventing bandage slippage. When the tertiary layer is applied over the point of the hock, less tension should be exerted to allow unrestricted flexion of the hock. Moreover, elastic adhesive tape must be used to secure the bandage to the skin at its proximal and distal limits. Figure 7.5 shows the progression of bandage placement over the hock. Because the bandage may split over the point of the hock when the horse flexes its limb, a strip of elastic tape may be placed along the plantar surface, over the tertiary layer of the bandage, to reinforce that area without increasing pressure on the underlying skin (Figure 7.6). Placing a distal limb bandage after applying a tarsal or carpal bandage is often helpful to prevent the latter from slipping distally (Figure 7.7). Many horse owners find the hock difficult to bandage due to its conformation. Consequently, they may use various readily available materials, such as pantyhose or Velcro strips, to create an innovative bandage. The veterinarian must remain in contact with the owner and frequently verify that all is well with the horse and its bandage to ensure against constriction or rubbing.

Restricting carpal flexion by applying a full‐limb bandage may be beneficial if the wound is located on the dorsal surface of the carpus. To apply a full‐limb bandage, cotton padding is used to cover the entire limb (from the coronary band or fetlock to the proximal radius) once the dressing has been secured over the wound. The separate rolls of cotton used to span the entire distance should be overlapped to avoid the formation of a gap between two rolls. An elastic, self‐adhesive material, such as Vetrap™ is then applied as a tertiary layer in the same fashion as for a distal limb bandage, and a relieving incision is made over the area of the accessory carpal bone. It may be easier to first apply all layers of the distal limb bandage and then add the proximal bandage, overlapping slightly at the proximal cannon bone; this avoids the need to hold the full length of cotton padding in place while applying the tertiary layer of Vetrap™. A full‐limb bandage can be applied in similar fashion to the hindlimb; in that case, the tertiary layer must be applied with less tension over the point of the hock than over the rest of the limb.

When greater restriction of flexion is desired, a compact, multi‐layered bandage, known as a Robert Jones bandage, can be applied. This might be appropriate when managing a wound over the plantar surface of the hock or a transversely oriented wound across the dorsal surface of the carpus; in both these instances, joint flexion would force the wound edges apart. In the case of a Robert Jones bandage, multiple secondary and tertiary layers are applied consecutively to the limb to build a uniformly compact bandage encompassing the entire limb. This thicker bandage will limit movement more than would a simple bandage.

Alternatively, a splint can be added to the palmar surface of a conventional forelimb full‐limb bandage, or a full‐limb cast can be used. In the case of a wound to the hindlimb, a splint made from cast material can be applied dorsally to a full‐limb bandage to partially immobilize the hindlimb or a full‐limb cast can be applied to support the repair of a large wound on the plantar surface of the metatarsus. The benefits provided by a full‐limb cast should be carefully weighed against the potential negative consequences (discussed in the following section on splints and casts).

Head bandages

A head bandage is useful to protect the repair of a head wound or a wound left open to heal by second intention, and to exert a small amount of pressure that might control the development of subcutaneous emphysema in the case of sinus penetration. Special attention to positioning and maintaining a head bandage is required to avoid ocular trauma or occlusion of the nostrils.

A simple head bandage consists of an appropriate dressing, followed by the placement of a mesh stockinette (Figure 7.9a) over the head, with holes cut out for ears and eyes (Figure 7.9b). The extremities of the stockinette can be attached to the skin with an elastic adhesive tape such as Elastikon®, placed without tension, half on the stockinette and half on the adjacent skin (Figure 7.9c). An extra length of elastic adhesive tape may span the stockinette where it covers the dressing, in an effort to secure the dressing to the surface of the wound and prevent slippage under the stockinette (Figure 7.9d). Additionally, gauze may be slipped under the stockinette over the dressing to exert gentle pressure on the wound, if required. The elastic adhesive tape can be wrapped in a figure‐of‐eight pattern between the eyes and around the mandible, rostral to the eyes, and then behind the ears and under the mandible, if more pressure is required to prevent emphysema or swelling from developing (Figure 7.9e). This is useful for wounds involving the sinuses. Care should be taken to avoid wrapping too tightly around the rostral extent of the bandage, which might prevent the mouth from opening, or around the throatlatch region, which could hinder swallowing or breathing. A finger should slide easily between the bandage and the skin of the throatlatch. Following enucleation, the figure‐of‐eight pattern with one length of the elastic adhesive tape passing over the incision is used to apply gentle pressure to the wound and to prevent the horse from rubbing the sutures. This figure‐of‐eight bandage is also used following repair of fractured frontal bones.

Commercial fly masks and helmets designed for the transport of horses may also be used either on their own or alongside bandages. Commercial masks with eye cups are recommended to protect an injured eye that is receiving treatment. Elastic head wraps, developed commercially for the purpose of “calming” a horse, make excellent head bandages and can be used over the stockinette in place of the elastic adhesive tape, although they are not useful for applying pressure, if that is required.

Bandaging ears that have been lacerated or partially amputated is challenging; care should be taken to avoid wrapping too tightly (the reader is referred to Chapter 11 for more information on bandaging an ear).

Thoracic and abdominal bandages

When a wound is located on the thoracic or on the abdominal wall, bandaging is sometimes required to prevent the formation of ventral edema or the accumulation of fluid in dead spaces, due to gravity. Conversely, bandaging is usually not indicated for wounds involving the axillary or inguinal areas. In these cases, the wound opening should remain as unobstructed as possible to allow ventral drainage and to avoid the trapping of air within the wound and surrounding subcutaneous tissues, which could lead to the development of emphysema.

To bandage a wound in the thoracic or abdominal area, the dressing is placed against the wound and overlaid by a secondary layer of cotton padding. The tertiary layer is then applied to hold everything in place and to mildly compress the wound. The best way to hold the bandage in place is to wrap the tertiary layer, often an elastic adhesive tape such as Elastikon®, around the circumference of the trunk. To ensure appropriate tension without restricting breathing, there should be room for a finger to slide easily under the bandage. Body bandages require a large amount of material and, consequently, they can be costly. An alternative to the classical tertiary layer is an adaptable commercial abdominal bandage (Figure 7.10). Because it can be laundered, it is especially useful for exudative wounds that require frequent bandage changes.