Use of Mechanical Stretching to Treat Skin Graft Contracture

Abstract After transplantation, skin grafts contract to different degrees, thus affecting the appearance and function of the skin graft sites. The exact mechanism of contracture after skin grafting remains unclear, and reliable treatment measures are lacking; therefore, new treatment methods must be identified. Many types of centripetal contraction forces affect skin graft operation, thus leading to centripetal contracture. Therefore, antagonizing the centripetal contraction of skin grafts may be a feasible method to intervene in skin contracture. Here, the authors propose the first reported mechanical stretching method to address contracture after skin grafting. A full-thickness skin graft model was established on the backs of SD rats. The skin in the experimental group was stretched unilaterally or bidirectionally with a self-made elastic stretching device, whereas the skin was non-stretched in the control group. The rats were sacrificed 2 weeks after stretching. The area, length, and width of the skin were measured. The grafts were cut and fixed with formalin. Routine paraffin sections were stained with hematoxylin-eosin, picric acid-Sirius red, Victoria blue, and anti-alpha-smooth muscle actin (SMA). Mechanical stretching made the graft lengthen in the direction of the stress and had an important influence on collagen deposition and alpha-SMA expression in the graft. This method warrants further in-depth study to provide a basis for clinical application.