Use of an implantable transducer to measure force in the superficial digital flexor tendon in horses at walk, trot and canter on a treadmill.

The study investigates the force exerted on a horse’s superficial digital flexor tendon (SDFT) during various speeds of movement and provides insights on measures that could prevent injuries.

Objective

The primary aim of the research is to measure the force applied to the SDFT in horses during different gaits such as the walk, trot, and canter using a treadmill. Understanding these forces could help identify what leads to injury in the tendon and inform prevention strategies.

Methods

• The researchers used Arthroscopically Implantable Force Probes (AIFP) to measure the forces exerted on the SDFT.
• Eight Thoroughbred horses, weighing between 480 and 565 kg, had these probes implanted in the SDFT of both their left and right forelimbs.
• The researchers then calibrated the output of the AIFP using the force in the SDFT calculated via inverse dynamics, using an in-vitro model of the lower forelimb trotting.
• The output from the AIFP was recorded at a frequency of 1000Hz as the horses navigated through the different paces of walk, trot, and canter on a flat treadmill.

Results

• The data from the AIFP could be analysed successfully from 13 measurement sessions taken while the horses were walking and trotting.
• While cantering, data from the leading forelimb was recorded 8 times, and from the trailing forelimb five times.
• The study found that the average maximum force in the SDFT was 3110 ± 1787 N during the walk, 5652 ± 2472 N at the trot, 7030 ± 2948 N in the lead forelimb at the canter, and 6453 ± 2940 N when it was the trailing forelimb at the canter.

Conclusions

• The results indicate that the force experienced by the SDFT in horses increases as the speed of the animals’ gait increases from walking to trotting up to cantering.
• However, the researchers weren’t able to measure the force in the SDFT during the gallop.
• Further research is suggested to determine the force in the SDFT at higher speeds since understanding these forces is crucial to prevent tendon injuries in horses by restricting its overloading.