BIOMECHANICAL RATIONALE FOR PERFORMING INCISIONS AND SKIN FLAPS IN THE SUPRAORBITAL AREA

Abstract

Currently, there are several theories regarding the existence of biomechanical systems that determine the direction of tension and relaxation lines. In our opinion, the optimal system is the “relaxed skin tension lines”, which are formed in the form of a linear groove when compressed in the form of a pinch of relaxed skin and are considered the gold standard for planning the design of facial incisions according to many researchers. It is a well-known fact that the risk of hypertrophic or keloid scars is due to abnormal wound healing, which extends the initial inflammatory phase far beyond the boundaries of epithelialization. The aim of the study was to biomechanically substantiate the degree of detachment, time, and degree of relaxation of the skin of the supraorbital area. 27 dolichocephalic patients and 26 brachycephalic patients who underwent planned surgical interventions in the supraorbital area were examined. During biomechanical studies, the dependence of all indicators studied on the shape of patients’ skulls was established. The instantaneous modulus of elasticity in brachycephalics was 9.5% higher than in dolichocephalics; the maximum allowable skin flap tension was 29.7% higher, the stress relaxation time was 49.9% higher, and the biomechanical limit of lateral detachment was 2.8 times higher, respectively. However, the degree of skin flap relaxation in brachycephalics was 20.9% lower than in dolichocephalics. Conclusions. Thus, when planning surgical incisions and the degree of skin flap detachment in the supraorbital area, the shape of the patient’s skull should be taken into account to reduce the risk of hypertrophic scars in this location