Multimodal assessment of the skin biomechanical properties during wound healing and hyaluronic acid response.

Various methods such as elastography or mechanical testing have been developed to quantify the mechanical properties of soft tissues, which are related to the tissue local pathophysiological conditions. This study is the first one to investigate the in vivo performances of the Impact-Based Analysis Method (IBAM) to characterize the biomechanical behavior of skin during physiological mechanisms. A murine model (12 Sprague-Dawley rats) was considered and various measurements of skin mechanical properties were conducted on different regions of interest over a 3-week period. The effects of wound healing after full-thickness excisional wound and an intradermal hyaluronic acid (HA) injection were monitored using IBAM, as well as two commercially available devices: Cutometer® and MyotonPro®. The indicators Δt (from IBAM), R0 and R5 (from Cutometer®) vary significantly as a function of wound healing time, which corresponds to a stiffening of healing tissue compared to healthy tissue. The indicator Δt and S (from MyotonPro®) are significantly different when HA was injected compared to healthy tissue, which also corresponds to less stiff tissue. Additionally, both IBAM and Cutometer® detect significant biomechanical variations in superficial soft tissue related to tissue growth in all measurement regions. This first in vivo use of IBAM shows that IBAM could assess significant variations related to wound healing or regeneration mechanisms following HA injection. This study paves the way for the development of a simple, low-cost and objective device. Future clinical studies or other animal models should be carried out to confirm these results.