Development and Mechanical Evaluation of a Novel Segmental Braided–Knitted Nitinol Stent with Enhanced Migration Resistance for Malignant Large Bowel Obstruction

Colorectal cancer causes high mortality, with malignant large bowel obstruction (MLBO) affecting up to 20% of patients. Self‐expanding metal stents (SEMSs), especially nitinol‐based (nickel‐Titanium alloy), are standard for MLBO but struggle to balance radial strength, flexibility, and migration resistance. This study presents a segmental nitinol stent (S‐stent) that uses braided and knitted structures, with braided segments for radial support and flanged anchorage linked by flexible knitted loops. Finite element analysis (FEA) optimized the stent's design. In vitro mechanical testing compared the S‐stent to a commercial braided stent, showing the S‐stent had higher flange radial force (6.02 ± 0.49 N vs. 2.54 ± 0.14 N), better compression recovery, superior bending flexibility, and 22% more pullout resistance, with reduced foreshortening and improved anatomical fit. FEA matched experimental results, showing the S‐stent localizes stress, reduces migration, and maintains lumen patency or normal flow. This advancement offers improved migration resistance and mechanical performance without sacrificing flexibility or safety.