Investigation of lower-limb tissue perfusion during loading

Area of Science:

• Biomedical Engineering
• Biomechanics
• Physiology

Background:

• Assessing soft tissue mechanical properties is crucial for understanding tissue viability.
• Amputee residual limbs present unique challenges for tissue assessment due to altered biomechanics and potential perfusion issues.
• Existing indentation devices lack integrated physiological monitoring capabilities.

Purpose of the Study:

• To modify an existing tissue indentor with laser Doppler flowmetry (LDF) for simultaneous mechanical and perfusion measurements.
• To quantitatively assess the mechanical and physiological responses of lower-limb soft tissues to indentation.
• To explore potential biomarkers for tissue viability in amputee residual limbs.

Main Methods:

• An existing tissue indentor was retrofitted with a laser Doppler flowmetry probe.
• Indentation tests were performed on the lower-limb tissues of healthy young subjects.
• Measurements included indentation depth, applied load, and tissue perfusion changes over time during loading and unloading cycles.

Main Results:

• The modified device successfully measured tissue perfusion changes in response to indentation loads.
• Relative changes in tissue perfusion and time delays in perfusion response were quantifiable.
• Data demonstrated the feasibility of assessing the dynamic interplay between mechanical load and tissue perfusion.

Conclusions:

• The integrated tissue indentor and LDF system provides a novel method for evaluating soft tissue biomechanical and physiological responses.
• This technology can enhance the understanding of tissue viability in critical areas like amputee residual limbs.
• Further studies using this device may identify key risk factors for tissue complications in lower-limb amputees.