Steven F. Swaim, DVM, MS

ADJUSTABLE HORIZONTAL MATTRESS SUTURE

Consider using the adjustable horizontal mattress suture technique when the skin around a wound can be stretched to close it. The procedure lends itself well to use on distal limb wounds, such as automobile-induced degloving injuries, in dogs.

After performing appropriate wound management, place a continuous intradermal suture with 2.0 monofilament (nylon or polypropylene) along the wound's length. Place a small sewing button on each end of the suture, extending from the wound's ends. Apply even tension on the suture ends to carefully pull the wound edges as close together as possible. Next, place small removable fishing weights, or split shots, on the suture adjacent to the buttons to hold the suture tension. Over time, stress relaxation in the skin occurs. Daily tightening of the suture gradually pulls the wound edges closer together and may result in full wound closure.

Advantages and important pointers

Using this technique, I have been able to close many distal limb wounds much faster than if I had treated them as open wounds and allowed them to heal by second intention. Early wound closure is pleasing for all concerned—the animal, pet owner, and veterinarian. In addition, open wound therapy can be applied while the wound edges are being pulled together.

A biologic tourniquet can result if the suture is pulled too tight. But because the suture is adjustable, it can be loosened, and a slower rate of tightening can be started at a later time. Also, be cautious not to use the technique on a limb wound that is very wide because the suture could cut into underlying tissue as it is tightened.

MESH SKIN GRAFT

When faced with a distal limb wound of such a magnitude that stretching the surrounding skin for closure is out of the question, you must consider replacing the skin. Skin replacement is also needed if a wound has healed as much as it can by second intention and there is insufficient skin for complete healing. In such instances, consider a mesh skin graft. The term skin graft often causes trepidation. However, a graft can be done with no special skill and by using everyday equipment.

Technique overview

After a healthy wound bed has been established, prepare the area around the wound and a ventral craniolateral thoracic donor area for aseptic surgery. Cut a pattern of the wound from a sterile cloth, towel, or glove wrapper. While the pattern is still on the wound, mark the side of the pattern that faces away from the wound, and be careful not to turn the pattern over when transferring it to the donor site. Thus, you don't inadvertently excise a mirror image graft. Trace the pattern on the donor site by dipping a sterile toothpick in sterile methylene blue.

After cutting the graft and removing it from the donor area, stretch it on a piece of sterile, corrugated cardboard by using hypodermic needles. Remove all subcutaneous tissue with scissors and thumb forceps, and make staggered, parallel rows of 1-cm-long incisions with a No. 11 scalpel blade to mesh the graft. Remove the graft from the cardboard, place it on the wound, and suture or staple it to the wound edges. Place interrupted tacking sutures between some mesh holes to immobilize the graft on the wound.

Apply a thin layer of 0.1% gentamicin sulfate ointment to a sterile, nonadherent absorbent bandage before placing it over the graft. Then place the secondary and tertiary bandage layers. Change the bandage daily the first week, every other day the second week, and once or twice the third week.