Wound healing: relationship of wound closing tension to tensile strength in rats

A study was conducted to better define the relationship between closing tension and the resulting tensile strength of scars in incisional wounds. Five groups consisting of ten hairless rats 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. The tensile strengths were determined at 28 days. Higher mean tensile strengths were demonstrated in the two groups requiring the highest closing tensions (45 mm and 60 mm of skin excision) with P = 0.0028 and P = 0.00016, respectively. A logarithmic relationship between closing tension and tensile strength was demonstrated using linear regression analysis with t = 6.18, p less than .0001, and R2 = .44.