Abstract The anatomy and histology of the rectal muscular cuff was studied in 15 dogs with an ileal pouch-anal anastomosis. Eight channel, three-dimensional anal manometry showed normal maximal squeeze presure (128 ± 20mm Hg) compared to a control group (135 ± 4 mm Hg). The rectal muscular cuff showed complete absence of the cuff in three cases. In 12 dogs, the rectal cuff was retracted to a length of less than 1 cm, the muscle fibers were degenerated and fibrotic. The results in the canine model and the clinical results of patients with an ileal pouch-anal anastomosis with a cuff demonstrated that a rectal muscular cuff is not essential to maintain continence after ileal pouch-anal anastomosis.