In Vivo Measurement of Plantar Tissue Characteristics and Its Indication for Foot Modeling

Area of Science:

• Biomechanics
• Musculoskeletal Disorders
• Medical Imaging

Background:

• Plantar heel pain is a prevalent musculoskeletal disorder causing chronic discomfort.
• Understanding the biomechanical factors influencing foot deformation is crucial for effective treatment.

Purpose of the Study:

• To investigate the impact of plantar tissue stiffness and thickness variations on human foot deformation.
• To combine in vivo measurements with finite element modeling for a comprehensive analysis.
• To explore the role of individual heel pad layer properties in foot biomechanics.

Main Methods:

• Utilized supersonic shear wave elastography for in vivo measurement of heel pad tissue stiffness and thickness.
• Developed a finite element model of the foot with distinct heel pad layers (dermis, micro-chamber, macro-chamber).
• Performed sensitivity analysis to assess the influence of tissue property variations on foot deformation.

Main Results:

• Heel pad micro-chamber layer stiffness decreased with age (24.7 kPa to 18.8 kPa).
• Plantar soft tissue stiffness and thickness were generally greater in males than females.
• Variations in heel pad tissue properties caused up to 27.5% change in heel pad strain, significantly affecting calcaneus stress and plantar pressure.

Conclusions:

• Individual variations in plantar soft tissue properties substantially influence foot biomechanics.
• Personalized foot models must incorporate individual anatomical geometry and soft tissue material properties.
• This approach is essential for accurate biomechanical assessments and treatment strategies for plantar heel pain.