NPLEX Minor Office Procedures Practice Test

The key idea is how a suture pattern directs tissue edges when you tighten it. A vertical mattress stitch uses a deep bite on each side followed by a shallow bite near the skin. When you tie the knot, the deep portions pull the deeper tissue toward the center of the wound, while the near bites help approximate the surface. The combined effect is that the tissue edges tend to turn inward rather than curl outward. That inward turning is what we mean by tissue inversion in this pattern.

So this pattern actively inverts tissue, rather than everting it or leaving it unchanged. It also engages deeper tissue along with the surface, not just epidermal closure.