A comparison of different established and novel methods to determine horses' laterality and their relation to rein tension.
Authors: Kuhnke Sandra, König von Borstel Uta
Journal: Frontiers in veterinary science
Summary
# Editorial Summary: Determining Equine Laterality and Its Effect on Rein Tension Laterality assessment in horses remains poorly standardised, with nine different testing methods producing inconsistent results that fail to correlate with one another or with ridden performance. Kuhnke and König von Borstel compared these approaches—ranging from ground-based tests to ridden observations—across 67 warmblood-type horses and 61 Thoroughbreds, using statistical measures of agreement (Cohen's kappa) and analysing rein tension symmetry through linear mixed models. Whilst non-ridden laterality tests showed negligible agreement with riding-context assessments, the rider's subjective evaluation of their horse's laterality correlated significantly with actual rein tension symmetry (p = 0.003) and aligned substantially with a newly developed method measuring hindquarter lateral displacement (p = 0.0003); notably, 73% of warmbloods consistently displaced their hindquarters rightward, though Thoroughbreds showed no significant directional bias. These findings suggest that laterality manifests differently depending on context and measurement approach, but practical rider perception—combined with objective observation of hindquarter positioning during ridden work—provides meaningful insight into rein tension balance and training symmetry. Given that matching horses and riders by laterality may stabilise rein tension and support more consistent training outcomes, professionals should prioritise ridden assessments and hindquarter observation over ground-based tests when evaluating laterality for management and riding purposes.
Read the full abstract on PubMed
Practical Takeaways
- •Ask the rider directly about their horse's laterality preference during ridden work—this assessment correlates better with actual movement and rein tension than ground-based tests
- •Be aware that most warmbloods naturally displace hindquarters to the right; matching this with rider preference could reduce asymmetric rein tension and improve training efficiency
- •Different laterality assessment methods measure different aspects of sidedness; choose your assessment method based on what you actually need to know about the individual horse
Key Findings
- •Laterality tests performed outside riding context showed poor agreement with riding-based assessment and with each other (p > 0.0018)
- •Rider's subjective assessment of laterality correlated significantly with rein tension symmetry (p = 0.003) and hindquarter lateral displacement (p = 0.0003)
- •73.1% of warmbloods showed right-sided hindquarter displacement versus 60.7% of Thoroughbreds, with only warmbloods showing significant deviation from equal distribution (p < 0.0001)
- •Horse-rider laterality matching may improve rein tension stability and training consistency