WHAT CAUSES SADDLE SLIP
The relationship of lameness, saddle slip and back shape in the general horse population
The cause of a saddle slipping to one side is called saddle slip. Saddle slip is usually blamed on poor saddle fit, crooked riders or asymmetry in the shape of the horse’s back, but we recently demonstrated a causal relationship between hindlimb lameness and saddle slip. When lameness was abolished by local analgesia, the saddle slip resolved. However, there were no studies of the frequency of occurrence of saddle slip and risk factors within the general sports horse population. We, therefore, performed a study to quantify the frequency of saddle slip and to describe the association with lameness, thoracolumbar shape/symmetry, crooked riders and ill-fitting saddles in a cross-section of the sports horse population.
Five hundred and six sports horses in normal work were assessed prospectively. Thoracolumbar shape/symmetry were measured at predetermined sites using a flexible curve ruler. Saddle fit and fit of any pads or numnahs were assessed. All horses were assessed trotting in hand and ridden by the usual rider. The presence of lameness (in-hand and/or ridden), saddle slip and crookedness of the rider was recorded. Statistics were performed to assess the relationship between horse-saddle-rider factors and saddle slip.
The frequency of lameness, quadrilaterally reduced cranial phase of the stride or stiff, stilted canter was 45.7%. Saddle slip occurred in 12.3%, of the horses. There was major left-right asymmetry of back shape in 0.6% of horses. One hundred and three of 276 riders (37.3%) sat crookedly. The saddle consistently slipped to one side in 30.3% of horses with hindlimb lameness, compared with 5.4% with forelimb lameness, 17.4% with stiff, stilted canter, 20% with quadrilaterally reduced cranial phase of stride and 5.6% non-lame horses. Nineteen horses (30.6%) with saddle slip had no detectable hindlimb lameness, however 14 had a gait abnormality, particularly in canter, for example crookedness, four-time canter, quality of canter worse on one rein compared with the other; or placing the hindlimbs unusually close together. The saddle had uneven contact in 93 horses (18.4%) and was unbalanced in 166 horses (32.8%).
Statistical analysis revealed that saddle slip was significantly associated with hindlimb lameness and gait abnormalities, with a risk of 52.6 times odds. Paradoxically a saddle fitted with even contact and uniform flocking was more likely to slip (15.5 times the odds) than an ill-fitting saddle; similarly a well-balanced saddle was more likely to slip (3.1 times the odds) than an unbalanced saddle. Saddles that bridge are more likely to be held in a fixed position than a well-fitting saddle. Saddle slip was also more likely for riders sitting crookedly (6.3 times the odds) than those sitting straight, however we believe that this is sometimes an effect of saddle slip rather than the cause. In the riders that rode more than one horse, those that were crooked when riding a horse with saddle slip usually sat straight on a horse without saddle slip. Horse with a round wide back shape at the level of the eighteenth thoracic vertebra were slightly more likely to have saddle slip (1.2 times the odds) than horses which were less round. This may reflect greater contact area between the horse’s back and the panels of the saddle. Therefore the saddle is more likely to follow the movement of the horse. A saddle may also be more likely to slip over a convex than a concave surface.
This study revealed a startling frequency of lameness in the general sports horse population. Clearly many horses with hindlimb and/or forelimb lameness go unrecognised. This study reinforced our previous observations that saddle slip may be a sign of hindlimb lameness. Education of the equestrian population to identify lameness and saddle slip is required.