Variation in frontal plane joint angles in horses.
BACKGROUND
Conformation in horses is often considered an indicator of athletic ability, performance and resistance to orthopaedic disease. Evaluation is performed in the standing horse and repeatability influenced by stance. Ground reaction forces increase in the moving horse as speed increases.


OBJECTIVE
To determine the effect of locomotion on equine carpus, tarsus, metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints in the frontal plane.


OBJECTIVE
Valgus/varus angulation will change when moving.


METHODS
Kinematic data were collected standing, walking and trotting for 2 groups of horses. The change in angle for carpus, tarsus, MCP and MTP joints was calculated standing and midstance for each stride. Comparison of joint angles between left and right limbs, standing, walking and trotting were made. Inter- and intrahorse variations were investigated.


RESULTS
Significant differences were observed between groups of horses and left and right forelimbs. Between walk and trot, the MCP joint changed from valgus to varus, and the tarsus and MTP joints increased in valgus deformity. Between standing and walk the carpus increased in valgus deformity. Interhorse variation was significantly different, intrahorse variation was not. Variation in measurements between gaits was minimal.


CONCLUSIONS
This study validates the measurement of joint angles from the front in the walking and trotting horse using kinematic data, interhorse variation in joint angle measurements exceeding intrahorse variation. The increases in joint angles between standing and walking, and walking and trotting warrant further investigation.
Department of Veterinary Clinical Sciences, The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK. vunt@rvc.ac.uk
V E
VE
Unt
J
J
Evans
S R
SR
Reed
T
T
Pfau
R
R
Weller
D000818:Animals; D001696:Biomechanical Phenomena; D005260:Female; D005552:Forelimb / Q000033:anatomy & histology* / Q000502:physiology; D005684:Gait; D006614:Hindlimb / Q000033:anatomy & histology* / Q000502:physiology; D006736:Horses / Q000033:anatomy & histology* / Q000502:physiology; D007596:Joints / Q000033:anatomy & histology* / Q000502:physiology; D008124:Locomotion / Q000502:physiology*