**Abstract**

In this article, I am presenting a variety of working models for closure of skin defects of different shapes along with their corresponding indications and mode of use. These working models can be enlarged or reduced in size using a regular copying machine in order to evaluate the best possibilities related to the position of the incision. The great advantage of this method is that the geometric results are always predictable. Furthermore, this method will improve the survival of the flaps and the cosmetic results. In summary, the surgeon can use a variety of skin incisions taking advantage of the minimal tension lines of the skin and also taking into consideration the anatomical characteristics of the region involved. In this article, I have used the minimal tension lines of the skin, because they are easy to demonstrate by simple measures, such as pinching of the skin in different directions. In addition, the surgeon can assess the mobility and the elasticity of the skin on an individual basis.

**Keywords:** skin defects closure, soft tissue flaps, pedicled skin flaps, reciprocal incisions, circular and semicircular incisions, triangular incisions, oval and elongated hexagonal incisions, skin minimal tension lines, relaxed skin tension lines

## **1. Introduction**

When excising large skin lesions, the ideal incision is a circular one, since most of the skin lesions are round, and because it provides an adequate margin of resection, and at the same time will avoid the removal of sound skin. The main problem with this approach is that the resultant circular defect may prove to be very difficult to close. To solve this problem, the surgeon can use different incisions that can be closed in a more expedite way and with better cosmetic results. Another alternative would be a split-thickness skin graft, which sometimes would not match the color or texture of the recipient area [1–3].

It is for these reasons that the surgeon has to use different methods such as using a rhombic or elliptical incision that leaves a long suture line and will waste more sound skin. In some cases, the circular incision can be transformed into a square incision, such as the Dufourmentel flap [4], or into a rhomboid defect, such as the Limberg flap [5], but both of them will generate loss of sound skin. The Limberg method for closure of a hexagonal defect uses three triangular flaps, but these flaps are rather small which may compromise their survival. Besides this, the resultant triangular suture line is not cosmetically acceptable.
