Biomechanical implications of uphill training on the aetiology of tendinitis.

This research investigates how uphill training can impact the development of tendinitis by studying the effects of treadmill inclination on the force experienced by a specific tendon in walking horses.

Introduction

• The study arises from prior observations that raising the toe during walking results in a slight reduction of strain in the superficial digital flexor tendon (SDFT) — a tendon in the horse’s leg. This observation led the researchers to question if walking uphill, which can resemble raising the toe, might lead to a similar reduction in SDFT strain.
• The importance of this is because strain or force in tendons is a key factor leading to tendon stress injuries. Thus, reducing tendon force could potentially prevent conditions such as tendinitis.

Methodology

• In order to test their hypothesis, the researchers implanted ‘Arthroscopically implantable force probes’ (AIFPs) into the SDFT of four horses.
• They then recorded the output from these probes while the horses walked on a treadmill at different inclines: leveled ground (0% incline), slight incline (3%), steep incline (8%), and then back to leveled ground (0% incline).

Results

• The results showed a significant decrease in the first peak of force in the SDFT when the incline increased from 0 to 8%, while the second peak of force saw a significant increase.
• However, the maximal force and the area under the force-time curve, which could infer the total force experienced by the tendon, remained unchanged.

Conclusion

• The researchers concluded that walking uphill on an inclined treadmill didn’t decrease the maximal force in the SDFT or the total force experienced (area under the force-time curve).
• However, the patterns of force on the tendon were altered, with the first peak of force decreasing and the second increasing as uphill walking was introduced.
• The study emphasises that future research should look at the force distributions of tendons and ligaments at faster gaits, since a change in hoof angle and slope may have larger effects at these faster speeds.