Lengthening of the colon for low rectal anastomosis in a cadaveric study: how much can we gain?

Lengthening of the colon for tension-free low rectal anastomosis comprises ligation of the inferior mesenteric vessels and splenic flexure mobilization. The aim of our study was to evaluate the length gained after each level of mesenteric vessel ligation with or without splenic flexure mobilization.

The length of the colon after each mobilization technique, that is, low ligation of the inferior mesenteric artery (IMA), high ligation of IMA, high ligation of the inferior mesenteric vein (IMV), and mobilization of splenic flexure, was measured in 13 cadaveric specimens. After each step, the colon and vessels were placed back in their original position.

The distance from the colosigmoid junction (CSJ) to the pubic symphysis (PS) was measured after each mobilization technique. The average elongation of the colon from original CSJ-PS distance to the CSJ-PS distance after low ligation of IMA, high ligation of IMA, high ligation of IMA plus splenic flexure mobilization, and high ligation of IMV was 2.08 ± 4.39 cm, 5.02 ± 5.51 cm, 8.20 ± 5.95 cm, and 17.98 ± 6.80 cm, respectively. The length of colon gained after IMV ligation was greater than the length obtained after low ligation of IMA, high ligation of IMA, and high ligation of IMA plus splenic flexure mobilization (p < 0.0001).

This study shows the objective length gained following each standard surgical technique in colonic mobilization for low rectal anastomosis. The maximum length gained is after high ligation of IMV.