Adaptation strategies of the Icelandic horse with induced forelimb lameness at walk, trot and tölt.
Authors: Smit Ineke H, Hernlund Elin, Persson-Sjodin Emma, Björnsdóttir Sigridur, Gunnarsdottir Helga, Gunnarsson Vikingur, Rhodin Marie, Serra Braganca Filipe M
Journal: Equine veterinary journal
Summary
# Lameness Detection in the Icelandic Horse: Why Walk and Trot Matter More Than Tölt Assessing forelimb lameness in Icelandic horses presents unique challenges due to their distinctive gaits, particularly the tölt—a four-beat lateral gait that differs fundamentally from conventional walk and trot. Researchers used inertial measurement units mounted across the head, withers, pelvis and all four limbs to track kinematic changes in ten horses before and after reversible forelimb lameness induction, measuring them at walk, trot and tölt both in-hand and ridden. Classical lameness indicators—specifically head and withers vertical movement asymmetry—proved highly responsive at walk and trot, with head drop asymmetry reaching 18.8 mm at walk and 24.0 mm at ridden trot, but these metrics performed poorly at tölt, where the minimum head drop failed to change significantly whilst maximum head elevation increased by 11.2 mm. Beyond kinetic parameters, the lame limb showed prolonged stance phase duration across all gaits, and pelvis asymmetry increased by 4.9 mm with altered diagonal dissociation patterns characteristic of tölt compensation. For equine professionals evaluating Icelandic horses—whether for competition fitness or clinical lameness—walk and trot remain the most reliable gaits for detection and quantification of forelimb injury, whilst tölt assessment requires different interpretive criteria and should not be evaluated using standard lameness metrics alone.
Read the full abstract on PubMed
Practical Takeaways
- •When assessing Icelandic horses for forelimb lameness, prioritize evaluation at walk and trot rather than tölt, as tölt masks traditional lameness indicators due to the gait's inherent dissociation pattern
- •Be aware that gaited horses modify their kinematic strategy differently than conventional breeds; monitor pelvis movement and diagonal dissociation at tölt as supplementary indicators when head movement changes are subtle
- •This controlled induction study applies only to mild acute lameness; clinical assessment protocols may need adjustment for chronic or severe cases in gaited breeds
Key Findings
- •Head vertical movement asymmetry increased significantly at walk and trot but not at tölt following forelimb lameness induction
- •Pelvis vertical movement asymmetry (PDmax) increased by 4.9 mm at tölt, with decreased sound side dissociation (-8.3%) and increased sound diagonal dissociation (6.5%)
- •Classical lameness metrics (head and withers vertical asymmetry) were less reliable at tölt compared to walk and trot, except for head maximum displacement (HDmax)
- •Stance duration of both forelimbs increased at walk, tölt, and in-hand trot in response to lameness