Joint moments in the distal forelimbs of jumping horses during landing.

The research explores the impact of tendon loading during jump landings in horses, and its potential role in causing tendon injuries in these animals. It finds that loadings in the flexor tendons were higher in the trailing than the leading limb, indicating that this may be a risk factor for horse athletes.

Objective and Methodology

• The primary objective of the study was to understand the cause of tendon injuries in athletic horses, hypothesized to result from excessive tendon loading during strenuous activities, such as jump landings.
• The researchers collected data on kinematics and ground reaction forces from the leading and trailing forelimbs of six experienced jumping horses. This data collection enables a quantification of tendon loading during a landing after a jump.
• They computed joint moments using a scientific procedure known as inverse dynamic analysis.

Results and Findings

• One of the key findings of the study was that the patterns of movement and loading were fairly consistent, with little variation observed within and between the horses studied.
• The research found that peak flexor joint moments in the coffin and fetlock joints were larger in the trailing limb than in the leading limb. Essentially, this means the load the tendons had to bear was much higher in the trailing limbs of the horses when they land from a jump.
• These joint moments in the fetlock and coffin joints in the trailing limb were roughly 82% and 45% (respectively) greater than the typical values given for trotting as found in existing literature.
• The study also discovered an extensor moment, an unexpected loading, in the coffin joint in the first half of the stance phase of the leading limb.

Conclusion

• In conclusion, the research found that tendon loading during landing from a jump was higher in the trailing limb — as opposed to the lead limb — of athletic horses, potentially contributing to tendon injuries in these animals.
• Additionally, there was also an unexpected loading of the extensor tendon in the leading limb during landing. This finding also demands further research to completely understand its significance.