Modeling of metamaterial based incision patterns for generating high expansions in skin grafts

Split-thickness skin grafting is a widely used treatment for burn patients. It requires removing a small portion of healthy skin, making parallel incisions on it, stretching it, and surgically implanting it into the burn site. Although skin graft mesher companies claim to significantly expand the size of the skin graft, in reality, the amount of expansion achieved is much smaller.

This study aimed to improve the expansion potential of skin grafts by designing new incision patterns with auxetic properties, using a skin simulant material and additive manufacturing. The mechanical properties and digital image correlation was used to analyze the strain, effective Poisson's ratio, local strains, void area, and meshing ratio of the auxetic skin graft simulants.

The results showed that the Y-shaped skin graft simulant had the highest effective negative Poisson's ratio, largest areal expansions, lowest maximum induced stresses and strains, and uniform strain distribution properties, making it the best choice for generating high expansions in skin grafts.

The study found that the expansions were highly strain sensitive, with higher auxeticity observed at lower strains. The novel findings with auxetic skin graft simulants are expected to provide valuable insights for developing skin grafts with higher expansion potential in the future.