A two scale modeling and computational framework for vibration-induced Raynaud syndrome

Area of Science:

• Biomechanics
• Vascular Biology
• Occupational Health

Background:

• Hand-Arm Vibration syndrome (HAVS) is linked to hand-held power tool use, causing peripheral circulation issues.
• The exact mechanism of vibration-induced vascular changes, like Vibration White Finger (VWF), remains debated, with hypotheses including mechanical stress and sympathetic nervous system involvement.
• Existing theories suggest vessel wall hypertrophy or thickening contributes to lumen reduction in HAVS.

Purpose of the Study:

• To model the mechanobiological growth of small distal arteries in response to vibration exposure.
• To predict geometrical and structural changes in arterial walls due to hand-held tool vibrations.
• To establish a theoretical basis for understanding vibration's impact on vascular structures.

Main Methods:

• Developed a multi-scale model separating macroscopic vibration dynamics from microscopic capillary growth.
• Validated a hyperelastic viscous dynamic model of fingertip cross-sections with experimental data.
• Utilized a Representative Volume Element (RVE) to transfer mechanical fields from macroscopic tissue to microscopic capillaries.

Main Results:

• The model predicts that vibrations significantly increase capillary wall thickness.
• This thickening leads to a reduction in the lumen diameter of the capillaries.
• Confirmed the hypothesis of vibration-induced reduction in blood vessel lumen.

Conclusions:

• Vibration exposure from power tools can induce pathological microstructural evolution in capillaries.
• The study provides a biomechanical framework for understanding vibration-induced vascular remodeling.
• Findings support the role of mechanical factors in the pathogenesis of HAVS.