Wound healing. Relationship of wound closing tension to scar width in rats

A study was conducted to better define the relationship between closing tension and the resulting scar width of incisional wounds. Five groups of 10 hairless rats each were studied. Transverse wounds were created and closed on the back of each rat, with closing tension varied by excising amounts of skin in widths of 0 (control), 15, 30, 45, and 60 mm. At 28 days, the scar width was measured by three methods: digital caliper, photographically, and histologically. Results showed that wounds closed under the highest tension (60-mm excision group) had significantly wider scars than controls by all three measurement techniques. Regression analysis of the caliper scar width as determined by squaring the closing tension resulted in a nonlinear equation resembling an exponential curve that "best fit" the variables.