Managing Skin Tension: Decision Making

1. Why is skin tension clinically important?

Excess skin tension creates many potential clinical problems, and increases the risk of local wound complications. This is why one of the most important basic principles of wound closure and reconstruction is to avoid tension. Closing wounds under tension particularly on extremities may create vascular and lymphatic compromise to distal areas or reduce perfusion to wound edges causing delayed healing or even complete wound disruption. Excessive extrinsic suture tension creates a high risk of suture cutout. In addition, this tension creates constant pain to the patient increasing the risk of self-trauma to the wound. For example, in a simple elective dewclaw removal (if excess skin is accidentally removed around the base of the digit), the wound is closed under tension, and this rather simple procedure winds up causing many problems such as pain, edema to the paw, infection, and wound disruption. These problems could have been avoided simply by reducing skin tension.

2. Preventing skin tension

A. Proper patient positioning
With proper preoperative planning, surgeons can avoid skin tension in their wound closures. Place the patient in a position during surgery to help free up surrounding skin, if possible.

B. Proper planning of incisions and wound closure
Especially in curvilinear wounds, plan the closure first by placing stay sutures in the middle or most difficult areas to close so that early suture placements do not restrict closure of more distant areas or create unnecessary dog-ear formation. Make incisions parallel to the natural lines of skin tension. This wound orientation reduces skin tension and also minimizes skin distraction during closure.

3. Managing skin tension

A. Pre-emptive skin tension management
Presuturing is a method of stretching skin with the use of large mattress sutures. Large suture bites are taken on opposite sides of a problematic wound or lesion scheduled for surgical removal or closure. As the skin sutures are tightened, the skin is pulled toward the central surgical area; the neighboring skin is placed under tension. Within a day, small amounts of skin can be stretched, (by mechanical creep mechanism) to help in wound closure. Mechanical creep is the biomechanical property in which skin is capable of further extension beyond the limits of its inherent extensibility by applying a stretching force to the skin. Collagen fibers progressively align to the force applied as the surrounding interstitial fluid is slowly displaced from around the compacting collagen fibers. As a result, the skin can stretch or advance beyond its natural extensibility. We experience this often when an apparently tight wound closure appears to be under significantly less tension the day following surgery. This method does not recruit significant amounts of skin, and is primarily used in distal extremities where elastic skin is limited. These sutures are not adjustable and the high load dissipates as the skin stretches. Unfortunately, presuturing is often uncomfortable to the patient.

Skin Stretchers is a system that allows skin to be stretched in a variety of directions around a wound. Specially designed anchor pads are “glued” to the skin, and elastic cables are connected to the opposing pads using a Velcro hook system. Clinical research has shown that skin stretchers are most effective in closing wounds involving the trunk, neck and head of the dog and cat. They may be effective in such clinical situations as: stretching skin prior to an elective surgical procedure (like a skin tumor excision) when closure is expected to be difficult, stretching skin in the later phases of open wound management, or application on opposite sides of a closed wound to prevent wound dehiscence. Skin is usually stretched sufficiently to close wounds within 2-3 days. Cable tension is increased in increments 4 times daily. After the stretching has occurred, the pads are removed manually or left in place to spontaneously separate within about a week after application. [...]