Skin graft meshing, over-meshing and cross-meshing.

INTRODUCTION: Split skin grafts (SSGs) are often meshed to increase their size and allow exudate to escape. We investigated the expansion obtained with meshing, and the possibility of re-meshing skin that has already been meshed ("overmeshing"). Both useful and inadvisable permutations are illustrated.
MATERIAL AND METHODS: Thin porcine SSGs were sideways meshed, or meshed with ratios of 1.5:1 and 3:1. Subsequently samples were over-meshed in a variety of ratios and directions. All grafts were maximally expanded and their areas calculated.
RESULTS: Meshed skin did not expand as much as suggested by the ratios displayed on dermacarriers. A 1:1.5 dermacarrier produced an area expansion of 1.36×, and a 1:3 meshing apparatus produced only a 1.80×area expansion. Several combinations of twice-meshed SSGs maintained integrity as long as over-meshing was done in the axis of initial meshing. Up to 2.3×expansion was obtained, by following a 1:1.5 mesh with a 1:3 mesh. We term this procedure as "overmeshing". Re-meshing in a direction orthogonal to initial meshing (cross meshing) cut the skin into small pieces.
CONCLUSION: Over-meshing a SSG can allow considerable further expansion, facilitating overgrafting of donor sites or simply increasing the area that can be covered with the existing harvested skin.