Healing of Incisional Wounds in Rats

Abstract

In a series of three experiments, tensile strength was related to orientation in both normal skin and in healing incisional wounds at 14 and 21 days. The tensile strength of normal rat skin is significantly greater parallel to wrinkle lines than at right angles to such lines. The healing dorsal skin incision varies physically and morphologically depending upon its orientation. At both 14 and 21 days, incisions parallel to wrinkle lines are significantly thicker and weaker than incisions oriented perpendicularly. Histologic examination supplemented the studies on wound healing. The principal morphologic difference between the two types of incision is found at the junction of newly-forming connective tissue and pre-existing dermal collagen. Under the conditions of this study, the incision parallel to wrinkle lines has no advantage in thickness or strength in comparison to a perpendicular incision.