Infrared thermographic imaging has been found by researchers to be useful in helping to determine saddle fit.
A correctly fitted saddle must accommodate the changing shape of a horse’s back under different gaits, in addition to allowing the rider to remain balanced.
Traditionally, horses are ridden with wooden-tree saddles which have panels filled with wool-stuffed flocking to allow distribution of the rider’s mass across the horse’s back.
In a poorly fitting saddle, the load tends to be distributed over a smaller area, leading to pressure peaks. The way a rider distributes weight on the saddle is also an important aspect that determines whether a horse can move easily and freely.
Research has shown that the overall force applied by a saddle pad is approximately equivalent to the rider’s body mass while the horse is walking.
However, as the horse’s gait changes, the force exerted by the rider also changes. During trotting, the force values increase to about twice the rider’s body mass, and at canter the force increases to 2.5 times that of the rider’s body mass.
For their study, Maria Soroko, Daniel Zaborski and their colleagues used infrared thermography to assess the impact of a rider and saddle on the saddle’s thermal distribution.
Eighteen clinically healthy racehorses, all three-year-olds, were ridden by four riders with their own racing saddle. All horses had a similar level of fitness and were trained daily for flat racing on a racecourse in Poland.
Their workouts comprised a 5-minute warm-up at the walk, 5 minutes of trotting, and 20 minutes of cantering (about 2200m).
Images of the saddle panels were captured at each of six thermographic examinations under controlled conditions.
On each image, six regions of interest where the weight of a rider is usually distributed were marked on the saddle panels, with the average temperature for each of those regions extracted.
In all, a total of 108 thermographic images associated with 31 horse-load combinations were analyzed.
Saddle fit was assessed on the basis of the degree of temperature difference between the regions of interest on the saddles, as well as deviations front to back and side to side.
Incorrect saddle fit, identified by an uneven thermal pattern, was indicated in 11 cases.
The researchers found that a difference in temperature between the saddle panels above 2 degrees Celsius suggested incorrect saddle fit. In their study, 25 (23.1%) of the 108 thermographic measurements had a temperature difference greater than 2°C.
There was evidence of rocking/bridging seen in the thermal patterns both front to back and side to side.
“Bridging has been identified as a major problem in saddle fit, where loading on the horse’s back is concentrated in the front and back of the saddle, and it is potentially detrimental because it causes focal distribution of the rider’s weight, rather than distributing it evenly over a larger area.”
The authors said infrared thermography was able to identify uneven thermal pattern distribution linked to poor saddle fit.
The results also suggest that the skills of the rider can have an influence on thermal pattern distribution, with certain patterns noticeable among the different riders.
“The observed asymmetry in surface temperature could have been caused by a number of factors, including movement patterns of the horse, asymmetry, rider balance and seat, and stiffness of both the horse’s and rider’s backs.
They concluded: “Infrared thermography examination is a useful diagnostic tool to conduct a preliminary assessment of potential problems with saddle fit.”
They said more could be learned by carrying out research that assesses any correlation between the results of infrared thermography and data collected from the use of saddle pressure mats.
The technology, they said, offered a rapid assessment of saddle fit in addition to an objective method of assessing the rider’s seat. It was a simple and non-invasive way to assess load based on the thermal pattern distribution in race saddles.
The full study team comprised Soroko, Daniel Zaborski, Krzysztof Dudek, Kelly Yarnell, Wanda Górniak, and Ricardo Vardasca.
Soroko and Górniak are with the Wroclaw University of Environmental and Life Sciences in Poland; Zaborski is with the West Pomeranian University of Technology in Poland; Dudek is with Wroclaw University of Technology, also in Poland; Yarnell is with Nottingham Trent University in England; and Vardasca is with the Universidade do Porto in Portugal.
Evaluation of thermal pattern distributions in racehorse saddles using infrared thermography. (2019) Soroko M, Zaborski D, Dudek K, Yarnell K, Górniak W, Vardasca R. PLoS ONE 14(8): e0221622. https://doi.org/10.1371/journal.pone.0221622