Basic three-dimensional kinematics of the vertebral column of horses trotting on a treadmill.

This research studies the movements of the vertebral column in horses during trotting with the intention to understand normal locomotion patterns in horses. The researchers used five young Dutch Warmblood horses for this study and investigated the kinematics of eight specific vertebrae in these trotting horses on a treadmill.

Methodology

• The study was performed on five young Dutch Warmblood horses which showed no signs of back problems or lameness.
• The horses’ vertebral column kinematics were determined by focusing on eight specific vertebrae – T6, T10, T13, T17, L1, L3, L5, and S3, along with both of their tuber coxae.
• The researchers used bone-fixated markers to track the movements of the mentioned vertebrae.
• The horses were trotted on a treadmill at a constant speed of 4.0 m/s and the measurements were recorded during this process.

Results

• The motion during the stride cycle was mainly characterized by a double sinusoidal pattern in the movements related to flexion-extension and axial rotation.
• One peak and one trough characterized the lateral bending movement.
• The ranges of motion were recorded for all investigated vertebrae as follows: flexion-extension ranged from 2.8 to 4.9 degrees; lateral bending from 1.9 to 3.6 degrees; axial rotation from 4.6 to 5.8 degrees. However, for vertebrae T10 and T13, axial rotation decreased to 3.1 and 3.3 degrees, respectively.

Conclusions

• The study concludes that three types of rotations — flexion-extension, lateral bending, and axial rotation — are evident in the thoracolumbar vertebrae during trotting.
• There are regional differences in the shape and timing of these rotations. These differences appear to be related to corresponding limb actions.
• The method used in this study for direct measurement of vertebral column motion provides deep insights into the complex movements of the thoracolumbar portion of a horse’s vertebral column during trotting.
• Obtaining information about normal kinematics is crucial for a better understanding of abnormal function of the vertebral column in horses.