Biomechanical Impact of Partitioning Position and Angle on Post‐SPGJ Gastric Emptying

ABSTRACT Stomach‐partitioning gastrojejunostomy (SPGJ) improves gastric‐outlet obstruction outcomes, yet its biomechanical basis and geometric optimization remain unclear. Patient computed tomography (CT) data were used to reconstruct realistic SPGJ models. Computational fluid dynamics combined with a discrete phase model quantified velocity, wall pressure, particle‐retention time, and velocity under systematic variations of partitioning position (distal, mid, and proximal), partitioning angle (5°, 15°, and 25°; left‐ or right‐sided), and incision angle (60°, 75°, and 90°). Distal partitioning produced the lowest pressure drop and fastest emptying, whereas proximal partitioning channeled high‐speed flow toward the pylorus and prolonged retention. A ∼15° partitioning angle balanced flow restriction and clearance; extreme unilateral angles either increased particle stasis (left‐side) or slowed emptying despite reduced reflux (right‐side). A vertical incision (90°) further decreased pressure losses and shortened mean retention relative to oblique cuts. SPGJ biomechanics are highly geometry‐sensitive. Distal placement, a 15° partitioning angle, and a near‐vertical incision collectively optimize flow, reduce lesion contact, and accelerate gastric emptying, providing quantitative guidance for patient‐specific SPGJ design.