FORELIMB JOINT MOMENTS AND POWER DURING THE WALKING STANCE PHASE OF HORSES

Objective-To calculate normative joint moments of force and power for the forelimb of walking horses as a benchmark against which to compare these mechanical variables in horses with specific lameness. Animals- 4 Dutch Warmblood horses with no recent history of lameness. Procedure -Horses were walked by hand through the test area, and data from 5 wal king trials were collected for each horse. Two camera views were combi ned with vertical and craniocaudal ground reaction forces to calculate net moments of force in the sagittal plane across the carpal, metacar pophalangeal (fetlock), and distal interphalangeal (coffin) joints dur ing the stance phase of the forelimb. Mechanical power was calculated as the product of net joint moment and the joint's angular velocity. R esults-During the early part of the stance phase, the carpal joint had oscillating periods of energy generation and absorption against a pre dominant flexor moment, then an absorption phase at the end of the sta nce phase, as the carpus flexed into swing against an extensor moment. The fetlock absorbed energy in the early part of the stance phase, th en the terminal part was marked by a large generation of energy across the joint. A flexor moment was measured at the coffin joint throughou t the stance phase, and this coincided with a long phase of energy abs orption followed by a short phase of generation for push-off. Conclusi on-Consistency of the power data indicates that typical profiles of wo rk exist for each of the joints (carpus, fetlock, and coffin). Clinica l Relevance-Detection of changes to these profiles of work may contrib ute to diagnosis of specific lameness conditions.