Page 119 - Manual of Equine Field Surgery

Cast Application 115
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Figure 19-6 Foam padding applied before fiberglass Figure 19- 7 Applying fiberglass casting material.

casting tape is applied.

the cast and the limb and to protect the skin from

the fiberglass material. A variety of materials are

available for cast padding.1 A water-curable foam

padding" is commonly used and appears to de-

crease cast sores3 (Figure 19-6). The foam padding

should be set on the limb with only minimal

tension. The cast material should be applied with

only enough tension to avoid wrinkling. Each

turn should be overlapped by half a tape width.

The tension used when applying the cast material

can be increased gradually as the number of layers

in the cast increases. For most fiberglass cast Figure 19-8 Incorporation of a heel wedge into the

materials) the horse should be maintained in bottom of the cast. A partial roll of casting tape has been

recumbency for 20 minutes after cast application incorporated into the heel (left) and acrylic applied to
provide an even weight bearing surface (right).
to allow for curing.

Half Limb Cast strength compared with wider casting tape. Four-

A double layer of stockinette is rolled from the inch-wide cast tape should be used for subsequent

foot to above the carpus or tarsus and held in layers (Figure 19- 7). Cast material should be

place with towel clamps. The stockinette should applied with only enough tension to avoid wrin-

kling and with each turn overlapped by half a tape
fit snugly and be stretched to avoid wrinkles. A 2-

inch-wide felt strip is then placed over the width. Before the last layer of cast material is

metacarpal-metatarsal bones at the proximal limit applied, the stockinette is folded down and held

of the cast, which should be 2 cm distal to the in place by the last cast layer. Adhesive tape is used

carpal or tarsal joint. Custom support foam or to seal the proximal end of the cast. The entire

other cast padding material is applied starting length of cast should be covered in five to eight

proximally and working distally, with special layers of tape." Generally, five or six rolls of casting

attention paid to adequately cover the coronary tape are used in a half limb cast. Casts providing

band. This is immediately followed by a layer of mechanical support for severe orthopedic injuries

2- to 3-inch-wide casting material. The initial require more layers than do casts providing soft

2- to 3-inch layer allows better contouring of the tissue support for wound healing. A heel wedge

cast material to the limb but has decreased should be placed so that the toe and heel of the

cast are level when the limb is directly under the

horse (Figure 19-8). Acrylic or other durable

"Custom Support Foam; 3M Animal Health Care Prod- material is applied to the bottom of the cast to

ucts, St. Paul, Minn. prevent wear (Figure 19-9).