Abstract 2039: Limb Flexion Compresses The Anterior Tibial Artery And Changes Its Take-off Angle In A Sex-Dependent Manner

Abstract

Introduction: Peripheral Arterial Disease (PAD) operations and reconstructions continue to fail at high rates, particularly below the knee. During limb flexion, distal superficial femoral and popliteal arteries experience significant deformations that are thought to contribute to disease development, but the biomechanics of the tibial arteries below the knee have not been characterized. Methods: Perfused human cadavers (n=15, 81±9 years old, range 60-93 years, 9F/6M) were imaged with their limbs in standing (180°), walking (110°), sitting (90°), and fetal/gardening (60°) positions using Computerized Tomography (CT). Three-dimensional geometries of the below-knee arteries were reconstructed in Mimics software and used to assess the take-off angle of the anterior tibial artery (AT) and the distance from the AT take-off to the nearest AT side branch. Results: The AT take-off angle relative to the tibioperoneal trunk increased with more acute limb flexion, from 70±19° in standing to 81±24° in walking, 83±24° in sitting, and 89±27° in fetal/gardening postures (p<0.01 for all postures). The AT take-off angle was larger in females than in males (24% in standing and 35% in walking, sitting, and gardening postures, p <0.01), but there were no differences between left and right limbs of either sex (p=0.66-0.99). The distance from the AT take-off to the nearest AT side branch decreased with more acute limb flexion (p< 0.01 for all postures). Conclusions: Limb flexion increases the AT take-off angle in a sex-dependent manner and compresses the AT, potentially contributing to the differences in hemodynamics and arterial mechanics and affecting the development and progression of tibial artery pathology. A better understanding of the below-knee artery biomechanics can provide valuable insights for surgical planning and may lead to improvements in the success rate and durability of PAD repairs.