The si-449 chondroitin sulfate adhesion barrier significantly decreases postoperative adhesion rates in open rectal resection patients, offering a promising option for improving surgical outcomes.

• Adhesion incidence in the experimental group was 45% compared to 93% in the control group (p < .001).
• The si-449 barrier also led to significantly lower adhesion severity and extent with no safety concerns.

Surgeons may consider incorporating si-449 into their practice to potentially reduce adhesion-related complications following rectal surgery.