Study of the Kono-S Anastomosis Versus the Side-to-side Functional End Anastomosis

Inclusion Criteria: 1. Patients with Crohn's ileitis or ileocolitis requiring initial surgical resection. 2. Age of 18 years and older, male and female 3. All Phenotypes of Crohn's diisease will be included: nonpenetrating (B1), stricturing (B2), and penetrating (fistulating) (B3), according to the Vienna classification 4. The patients can be on any medications coming into surgery, including prior anti- tumor necrosis factor(TNF) therapy. Exclusion Criteria: 1. Patients under 18 years of age 2. Patients with recurrent Crohn's 3. Pregnant patients 4. Patients with more than one non-contiguous site of active disease, thus requiring multiple resections or additional bowel sparing procedures at the time of surgery. 5. Patients with Crohn's disease extending to the cecum and ascending colon 6. Patients who will need preventive postoperative medical treatment 7. Patients that need change of surgical procedure as per the surgeon at the time of the intraoperative abdominal evaluation.