An improved model for the induction of experimental adhesions.

BACKGROUND

The creation of ischemic buttons from parietal peritoneal tissue using a ligature is among the most established models for adhesion induction. However this model is plagued by slipping of ligatures and subsequent obliteration of the buttons when the animals mobilize postoperatively. Here we describe an improved model that involves creating the buttons with a backstitch ligature, and compare it to the traditional model.

METHODS

A total of 160 ischemic buttons were created in 20 adult Wistar rats. Ischemic buttons in the control group (n = 80) were created using the traditional technique whereas ischemic buttons in the investigative group (n = 80) were created using the novel technique with a backstitch ligature. The resulting adhesions and the frequency of slipped ligatures were analyzed on postoperative day 10.

RESULTS

Slipping of the ligature with obliteration of the button occurred in 18.8% (n = 15/80) of buttons in the control group and in 3.8% (n = 3/80) of buttons in the investigative group (p < .01). Adhesions formed to 69.2% (n = 45/65) of the remaining buttons in the control group and to 62.3% (n = 48/77) of the remaining buttons in the investigative group (p = .38).

CONCLUSION

There was no statistically significant difference in adhesion quantity between the models. However, the novel technique significantly reduced postoperative slipping of the ligatures with obliteration of buttons. As a result, a greater number of intact buttons are available for data collection. Furthermore slipped sutures, which act as foreign bodies in uncontrollable locations, no longer confound adhesion formation to the remaining buttons.