Kinematics of the equine back: a method to study the thoracolumbar flexion-extension movements at the trot.

The study presents a new method to quantify the flexion and extension movements in the back of trotting horses, which had been difficult to isolate before due to the limited nature of these motions. The method involves using a 3-D kinematic analysis system to track and analyze the positions of markers placed on the horse’s back.

Methodology of the Research

• The study utilized a 3-D kinematic analysis system to record and analyze the positions of four markers placed on the horses’ withers and tuber sacrale.
• The study team went further to isolate the flexion-extension movements by recalculating the positions of the four markers using a trunk-related co-ordinate system of the horse.
• The team found the best fitting third-order polynomial equation for the positions of the four markers for each frame, enabling them to interpolate the vertical displacement of any point on the horse’s back between the withers and the tuber sacrale.

Evaluation of the Method

• The accuracy of the method was evaluated using three additional markers placed between the previous four markers.
• The vertical displacements of the three markers were recorded and compared to the interpolated displacements produced by the new method.
• The results showed no statistical difference between the experimentally obtained and interpolated values, except in the lumbar region, where the study found the displacement curve shape to be conserved, but magnified by 17%.

Results and Conclusions

• The study demonstrated that the flexion-extension movements in the back of trotting horses could be reliably quantified using the new method, despite the movements’ limited range.
• The method was also applicable for studying flexion-extension movements in horses suffering from various locomotor disorders.
• This study represents an advancement in the veterinary field by providing a reliable method to quantify and analyze important locomotion patterns in horses, which could improve strategies for treating locomotor disorders in horses.