Relative effects of intraoperative tissue expansion and undermining on wound closing tensions

Intraoperative tissue expansion is advocated as a technique to facilitate closure of soft-tissue wounds with less tension than if they were closed primarily without expansion or, presumably, simple undermining. Few objective studies have been done, however, to validate the technique. We specifically questioned the relative effects of intraoperative tissue expansion and undermining on wound closing tensions in an animal model. Our data showed statistically significant reduction in the force required to close a wound after acute intraoperative tissue expansion when compared with baseline. However, when the degree of undermining achieved by the expander was matched in an equivalent defect, no difference in the resultant wound closing tensions could be discerned between techniques. This study should be viewed as an initial effort to understand the role of intraoperative tissue expansion in reconstructive surgery.