The Saddle Research Trust, a charitable organisation, was established to lead and support research into the influence of saddles on the performance of horses and riders. An inaugural workshop, hosted by the Animal Health Trust (AHT) in Newmarket, recently brought together the world’s scientific experts to discuss the interaction between horses, saddles and riders, in order to outline our current level of knowledge and major problem areas and questions, to promote discussion and to propose future areas for research. The meeting, also attended by veterinary surgeons, physiotherapists, rider representatives and members of the saddlery profession, comprised a series of keynote lectures followed by in depth discussions.

Anne Bondi, organiser of the meeting, set the scene by describing how the saddle had evolved, terminology related to the saddle and the importance of the relationship between not only the saddle and the horse, but also the rider.

Dr. Sue Dyson, Head of Clinical Orthopaedics at the AHT, discussed the complexities of differentiating primary back pain and back stiffness that was the result of either lameness or the way in which the horse had previously been trained and ridden. She emphasised the importance of saddle fit not only for the horse, but also for the rider, so that the rider was in a suitable position to ride in balance. Rider asymmetry, an inability to ride in balance, lack of fitness and lack of understanding of the principles of correct training could all lead to equine back stiffness and pain in either the horse, rider or both. However subclinical lameness could also masquerade as a primary back problem.

It was noted that the tendency of a saddle to slip to one side was often recognised as a potential cause of back pain. A saddle could slip because of asymmetry of the horse’s back, an ill-fitting saddle, the inability of a rider to sit straight, or secondary to hindlimb lameness. An on-going study had shown that in approximately 50% of horses with hindlimb lameness, the saddle consistently slipped to one side with more than 1 rider, despite symmetry of the back musculature and a well-fitting saddle. When the lameness was abolished by nerve blocks, the saddle no longer slipped, indicating that saddle slip may actually be an indicator of lameness.

Dr. Lars Roepstorff, a research veterinarian from the University of Uppsala, Sweden, considered methods to objectively evaluate forces transmitted through the saddle. This could be done using pressure-recording mats, comprising multiple sensors, placed beneath the saddle. This could generate huge amounts of information, including the distribution of forces from side to side and back to front, variation of forces over time and peak forces. However these mats are by no means perfect. They are designed to measure forces applied perpendicular to the sensors, but a horse’s back is curved and therefore pressure in many locations is not at right-angles to the sensors. It is difficult to differentiate rider and horse effects. The readings from the pressure mats can change over time and are dependent on a standardized position of the mat. He has therefore designed a system to analyse the effect of a rider in isolation from a real horse in a laboratory and is studying the way in which different elite riders sit and their ability to alter the forces applied to the horse’s back by movement of the pelvis. This can be done by placing inertial sensors in key positions on the rider’s back.

Dr. Narelle Stubbs, a human and equine physiotherapist from Michigan State University, America, discussed assessment of rider symmetry. Most people have a dominant leg and this can be assessed by their ability to stand on each leg independently and to squat and the way in which the arms are swung at the walk. In most people the right leg is slightly shorter and the more stable; the longer leg is the left. If arm swing when walking is asymmetrical this generally reflects leg length discrepancy. This can be translated through to their position on the horse. She described objective assessment of the muscles responsible for core stability by ultrasonographic assessment of the activity of transverse abdominis and internal and external abdominal oblique muscles. Applying lengths of sticky tape to certain muscle groups of the rider could help to both identify asymmetries of function and improve muscle function. The effect of the rider’s position could also be assessed objectively by placing a pressure mat on top of a saddle.

Dr. Christian Peham, a biomechanist by training and Head of Movement Science at the Veterinary School of the University of Vienna, Austria described a number of studies which had investigated saddle fit, types of saddle and a variety of pads and numnahs. He demonstrated that a saddle which was too wide for a horse increased the pressures exerted on the back. When comparing a conventional saddle with a sidesaddle at walk, trot and canter, there was greater movement of the sidesaddle. He assessed the differences between rising trot, sitting trot and standing in the stirrups (a 2 point seat) in a conventional saddle. The mean forces applied to the horse’s back were fairly constant, but the extreme values were reduced in both rising trot and a 2-point seat compared with sitting trot. The effects of various saddle pads were assessed, comparing gel, leather, foam and reindeer fur. With a well-fitting saddle only the reindeer fur pad reduced the force applied to the back. The use of any pad with a saddle which was too wide could actually make the situation worse.

Dr Hilary Clayton, a research veterinarian from the McPhail Performance Centre, Michigan State University, USA, reviewed the different methods for assessing the interactions between the saddle and the horse. She concluded that thermography was of limited benefit. The electronic pressure pads had value, but she questioned what measurements were of real importance. The maximum pressure exerted at any one site was not necessarily the key measurement. Changes in pressure might be more important.

The current pressure mats comprise an array of sensors on the left and right sides, joined at the middle. They did not evaluate pressures applied to the tope of the spine. This was potentially an important area to assess, and addition of a linear strip of sensors stuck to the gullet of the saddle may provide further useful information. The development of a 3D scanning technique to objectively map the shape of a horse’s back and changes over time was a valuable innovation which merited further investigation.

Following lively discussion and an overview of potential further areas for research, all the delegates voted for the topics which they considered should be prioritised. These topics were then discussed in 4 small groups led by Dr Rachel Murray, Head of Equine Orthopaedic Research at the Animal Health Trust, Dr Charlotte Nevison, Director of Equine Research at Anglia Ruskin University, Cambridge, Wayne Channon, Secretary General of the International Dressage Riders Club and Karen Coumbe, from the Bell Equine Clinic, Kent.

The brainstorming sessions were intellectually challenging and brought forward many different opinions. Clearly obtaining adequate funding to perform any meaningful research project is a huge issue. It was rather humbling to acknowledge how little we actually know. There were some projects that were considered potentially too difficult to address, such as what was the maximum weight that a horse of a specific size should be asked to carry. This seemingly simple question is actually very complex when you consider the variability in strength of horses related to size, the ability of an individual rider to ride in rhythm with the horse’s movement, the fitness of the rider, the duration for which the horse was ridden and many other factors. Further work needs to be done on riders in isolation to establish the range of motion required to accommodate the swing of the horse’s back. We need to know much more about the inter relationships between conformation of the horse’s back and movement. These are complex problems which require collaboration between people with different areas of expertise. This meeting brought together potential collaborators and hopefully we will see progress in knowledge about the interactions between the horse, rider and the saddle in the ensuing years.

The SRT is extremely grateful to its title sponsors, Solution Saddles and Sue Carson Saddles. Without the generosity and support of these organisations, this important meeting could not have been held.