A method for determination of equine hoof strain patterns using photoelasticity: an in vitro study.

This study focuses on understanding the strain patterns seen in horse hooves during impact using photoelastic stress analysis (PSA) while modifying loading conditions in vitro. The research indicates that PSA is a reliable method for evaluating hoof strains and can detect subtle changes related to loading alterations.

Objective of the Study

• The objective of this study was to identify the normal strain patterns in equine hooves during impact and how these strains may potentially cause harm.
• The study also aimed to evaluate the reliability and sensitivity of the Photoelastic Stress Analysis (PSA) method for such analyses in vitro.

Methodology of the Study

• The hooves were studied under various load conditions that simulate the different loads a horse’s hoof would bear in real life scenarios.
• A custom-made photoelastic plastic sheet was applied to the surface of the hoof to visualise and observe strain patterns.
• Horse hooves were loaded axially with 225 kg weight under level and varus/valgus (a term used to describe tilting of a part of the foot or ankle) conditions.
• The strain patterns were recorded through a device called a polariscope that measures optical properties.

Key Findings

• The study found that presumably harmful strains are concentrated between the middle and distal thirds (furthermost section) of the hoof wall, regardless of loading conditions.
• This strain distribution seems to be a result from the differential expansion of the hoof wall when under load.
• Increasing the load resulted in higher strains and asymmetric loading resulted in an increase in strain magnitudes on the same side without altering the position of the strain.

Conclusion and Implications

• The study concludes that Photoelastic Stress Analysis (PSA) is a reliable method for evaluating hoof strain patterns in vitro (outside the living body, in a controlled environment).
• PSA is also sensitive enough to reflect subtle alterations in strain related to changes in load.
• This research holds potential for advancing the study of equine health and understanding the impact of strain on horse hooves, aiding in the development of better hoof care and possibly, footwear materials.