Could Pressure Distribution Under Race-Exercise Saddles Affect Limb Kinematics and Lumbosacral Flexion in the Galloping Racehorse?

This study explores how varying pressures under different racehorse saddle designs can influence a horse’s limb movements and lower back flexibility during galloping. Reduced pressure at specific thoracic vertebrae seems to improve the kinematics of the horse’s lower back and limbs.

Objectives and Hypothesis

• The main hypothesis of this study is that reducing pressures under saddles at thoracic vertebrae 10-13 in galloping racehorses correlates with improved kinematics of the limbs and lumbosacral region (the lower back area where the spine connects to the pelvis).
• The researchers aim to measure the pressure exerted by different saddle designs on thoroughbred racehorses at gallop, and compare limb and lower back movements when different saddle designs are used.

Study Design and Methodology

• Four thoroughbred racehorses were part of this study. The researchers used a cross-over design, which means each horse was tested with all the saddle types in a randomized order.
• Four saddle types were tested – half-tree, three-quarter-tree, full-tree race-exercise saddles (referred to as saddles H/Q/T), and a saddle purposely designed to reduce pressure in the region of thoracic vertebrae 10-13 (referred to as saddle F).
• Pressure distribution under the saddles was recorded using a pressure-mat system, while limb and lower back movements were captured using high-speed motion capture technology.

Key Findings

• The study revealed that maximum peak pressures at the T10-13 vertebrae occurred during a specific phase of the gallop (the trailing forelimb vertical), but the pressure distribution varied significantly among the different saddle types.
• Comparative analysis showed that the pressure exerted, the femur’s angle to the vertical axis, and the hip-flexion angles were significantly different between the saddles. Specifically, Saddle F exerted significantly lower peak pressures at the T10-13 region and showed greater hip flexion, a better femur angle to the vertical axis, and increased protraction (forward extension) of both the forelimb and hindlimb.

Implications of the Findings

• The findings indicate that saddles that exert less pressure at the T10-13 region, like Saddle F, could potentially enhance a horse’s spinal range of motion and muscle use.
• It suggests that the femur exhibits greater forward extension with saddles that apply lower pressures at T10-13, underlining the importance of race-exercise saddle design in influencing a racehorse’s galloping kinematics.
• This insight into the role of saddle design and fit could support the improvement of hindlimb function in galloping racehorses and might contribute to reducing back pain instances in these animals.