The effect of trimming on movement symmetry over time in domestic horses
Authors: Horner
Journal: FWCF Fellowship Thesis
Summary
# Editorial Summary: The Effect of Trimming on Movement Symmetry Over Time in Domestic Horses Horner's 2019 research investigated a fundamental assumption in farriery practice: whether the conventional six-week trimming interval optimises movement symmetry. Using inertial sensor technology (Equinosis system), 26 horses aged 1.5–18 years were assessed for movement symmetry pre-trim, immediately post-trim, and at 2, 4, and 6 weeks following a standardised trimming protocol. Contrary to expectations, the study found a statistically significant *increase* in forelimb asymmetry by weeks 4 and 6 post-trim, whilst hindlimb symmetry showed no meaningful change. These unexpected results suggest that applying a uniform trimming protocol may not suit all horses equally and challenge the evidence base for routine six-week intervals as a one-size-fits-all recommendation. The findings warrant cautious interpretation of what "good" farriery outcomes should look like on an individual basis, and highlight the need for more nuanced trimming schedules informed by each horse's conformation, age, and movement patterns rather than calendar-based protocols.
Practical Takeaways
- •A one-size-fits-all trimming protocol may not be appropriate for all horse populations, and individual assessment of trimming needs is warranted
- •The conventional 6-week trimming interval recommendation warrants re-evaluation based on these unexpected findings of increased asymmetry post-trim
- •Movement symmetry assessment using objective inertial sensor technology should be considered to monitor individual horse responses to trimming rather than relying on standardized protocols
Key Findings
- •Statistically significant increase in forelimb asymmetry observed at weeks 4 and 6 post-trim compared to pre-trim, contrary to hypothesis
- •No significant change in hindlimb asymmetry following standardized trimming protocol
- •A standardized trimming protocol was associated with increased forelimb asymmetry rather than improved movement symmetry