The forelimb in walking horses: 1. Kinematics and ground reaction forces.
Authors: Hodson E, Clayton H M, Lanovaz J L
Journal: Equine veterinary journal
Summary
# Editorial Summary: The forelimb in walking horses: 1. Kinematics and ground reaction forces Hodson, Clayton and Lanovaz (2000) collected simultaneous high-speed video (60 Hz) and force plate data (2000 Hz) from five sound horses to establish detailed normative values for forelimb kinematics and ground reaction forces during walk, analysing eight strides per horse across the sagittal plane. The research revealed a clear temporal relationship between joint mechanics and propulsive forces: the coffin joint reaches maximum flexion during the contralateral forelimb's breakover, the metacarpus becomes vertical at 28% of stride (well before the transition from braking to propulsive forces at 34%), and propulsive forces peak shortly after the contralateral forelimb contacts the ground. Proximal limb movement—particularly brachial rotation—drives overall protraction and retraction, whilst distal joint rotations (scapula and antebrachium) control distal limb elevation during swing and positioning for ground contact, with distinct flexion peaks occurring at 76–84% stride depending on the joint. These normative kinematic and force data provide the baseline framework for identifying gait deviations associated with specific lameness presentations, making this foundational work invaluable for practitioners developing objective assessment protocols and for interpreting how pathology alters the coordinated sequence of limb and joint actions during locomotion.
Read the full abstract on PubMed
Practical Takeaways
- •Understanding normal forelimb kinematics and force patterns during walk provides a baseline for detecting lameness-associated deviations in motion and loading
- •The timing of metacarpal verticality (28% stride) and force transitions (34% stride) can serve as reference points when assessing forelimb function in lame horses
- •Abnormalities in joint flexion timing during swing phase or coffin joint behavior during braking phases may indicate specific forelimb pathologies
Key Findings
- •Brachial rotation is responsible for limb protraction and retraction during walking, while scapular and antebrachial rotations manage distal limb elevation and lowering
- •Coffin joint flexion peaked at the time of peak longitudinal braking force during contralateral forelimb breakover
- •Metacarpus reached vertical position at 28% stride, considerably earlier than the transition from braking to propulsive force at 34% stride
- •During swing phase, distal joints showed single flexion cycles peaking at 76% stride (carpus), 81% stride (fetlock), and 84% stride (elbow and coffin joints)