Impact of Wound Dressing on Mechanotransduction within Tissues of Chronic Wounds

Abstract

Chronic wounds are significant public health problems impacting the health-related quality of individuals' lives (due to disability, decreased productivity, and loss of independence) and an immense economic burden to healthcare systems around the world. In this study, our main objective is to investigate how mechanotransduction can impact the healing process in chronic wounds. We have developed new three-dimensional models of wound tissue to study the distribution of forces within these tissues exerted by wound dressings with different characteristics. The roles of mechanical forces on wound healing have gained significant clinical attention; the application of mechanical forces is expected to influence the physiology of tissue surrounding a wound. We aim to investigate whether the force transmission within wound tissue is impacted by the dressing characteristics and whether this impact may differ with wound tissue's properties. Our results show that wound dressings with lower stiffnesses promote force transmission within a wound tissue. This impact is even more significant on stiffer wound tissues. Furthermore, we show that size of wound dressing alters forces that transmit within the wound tissue where dressings with 9 cm length show higher stresses. The wound tissue stiffening has been associated with healing of a wound. Our results demonstrate that wounds with stiffer tissue experience higher stresses. Taken all together, our findings suggest that low stiffness of wound dressing and its size may be introduced as a criterion to explain parameters predisposing a chronic wound to heal. This study's findings on the role of dressings and tissue characteristics demonstrate that precision dressings are required for wound management and understanding how a dressing impacts mechanotransduction in wound tissue will lead to design of novel dressings promoting healing in chronic wounds.

Keywords: chronic wound; computer modeling; mechanotransduction; stiffness; tissue engineering; wound dressing; wound tissue.

Figure 1

Model of an idealized 3-D chronic wound: (a) Components of the model including (i) tissue, (ii) wound, and (iii) dressing; (b) Frontal view of the geometry and components with dimensions; (c) Aerial view of the geometry and components with dimensions.

Figure 1

Model of an idealized 3-D chronic wound: (a) Components of the model including (i) tissue, (ii) wound, and (iii) dressing; (b) Frontal view of the geometry and components with dimensions; (c) Aerial view of the geometry and components with dimensions.

Figure 2

Distribution of von Mises stress (N/m²) magnitude on the dressing and wound tissue. The stiffness of the tissue and dressing are 10 kPa and 50 kPa, respectively.

Figure 3

The von Mises stress values in accordance with the location on the tissue surface when dressing length is maintained at 7 cm.

Figure 4

The von Mises stress values in accordance with the location on the tissue surface when dressing length is varied from 9 cm to 11 cm: (a) ECM stiffness is controlled at 50 KPa; (b) ECM stiffness is controlled at 1 MPa; (c) ECM stiffness is controlled at 100 MPa.

Figure 4

The von Mises stress values in accordance with the location on the tissue surface when dressing length is varied from 9 cm to 11 cm: (a) ECM stiffness is controlled at 50 KPa; (b) ECM stiffness is controlled at 1 MPa; (c) ECM stiffness is controlled at 100 MPa.

Figure 4

The von Mises stress values in accordance with the location on the tissue surface when dressing length is varied from 9 cm to 11 cm: (a) ECM stiffness is controlled at 50 KPa; (b) ECM stiffness is controlled at 1 MPa; (c) ECM stiffness is controlled at 100 MPa.

Figure 5

The maximum von Mises stress value within a wound tissue for each of the cases in Table 1. (a) Shown as histogram, (b) The maximum of von Mises stress within a wound tissue, treated by different dressings, is plotted against wound tissue’s stiffness.