Small tissue bites and wound strength: an experimental study

HYPOTHESIS: Placing stitches close to the cut wound edge does not produce low wound bursting strength in midline laparotomy incisions closed with a suture length:wound length ratio of 4.

DESIGN: Experimental study in rats.

METHODS: Midline incisions were closed with a running suture in 51 Sprague-Dawley rats. A suture length:wound length ratio of 4 was used and stitches were placed at a distance of 3, 6, or 10 mm from the wound edge. Wound bursting strength was studied immediately after and 4 days after wound closure.

RESULTS: Immediately after wound closure, bursting pressure was higher with stitches placed 10 mm from the wound edge than those at a distance of 3 mm. After 4 days, bursting pressure and bursting volume were lower with stitches placed 10 mm from the wound edge than those at a distance of 3 or 6 mm. The abdominal wall ruptured outside the suture line in 14 of 17 wounds closed with 21 stitches, in 11 of 17 wounds closed with 16 stitches, and in 6 of 17 wounds closed with 11 stitches (P=.02).

CONCLUSIONS: Four days after closure of midline laparotomy incisions using a suture length-wound length ratio of 4, wound bursting strength is higher with stitches placed 3 to 6 mm from the wound edge than those at a distance of 10 mm. Wound bursting strength increases with the number of stitches used.