Back Conformation in Horses
Ideal Back
An ideal topline can vary between different breeds of horse. This here is an ideal back in a warmblood. An ideal back is when the whither and the highest point of their hip are level, and the horse is neither roached or swaybacked. --- The length a horse or ponies back may affect smoothness of gait, their ability to collect and agility. It also limits how much weight the horse can carry, and can impact if a horse capable of being gaited. The height of the withers also varies and affects freedom of shoulder movement and length of stride.
Short Back
If a horses back measures less than 1/3 of its overall length from whither to tail, it would be considered short backed. It is common in American Quarter Horses, Arabians, and some Warmbloods, but can be seen in any breed. If their spine is short, they may have a difficulty with bending, have less flexibility, or even develop arthritis. Overreaching is more common in short backed horses. However, these horses can be very agile, and are good for polo, roping, cutting, and reining as they can change direction with ease.
Long Back
If a horses measures greated than 1/3 of its overall length from its whither to tail, it would be considered long backed. It can be seen in Saddlebreds, Thoroughbreds, Pase Finos and some Warmbloods. It is also common in gaited horses. Usually associated with long, weak loins. The horses ability to engage its back depends on its ability to elevate its back, which requires a strong back and abdominal muscles. Long backed horses often have more difficulty collecting engaging their hindquarters, which affect upper level dressage, cutting, reining, barrel racing, and polo. However, their long back gives a quieter and smoother ride. Because long backed hoses have more difficulty building strength in their backs, they can become swayed more easily
Roach Back
This is when the area where the back and loins join the croup has an upward convex arch in the spine. Often a result of a short back, or injury or displacement of the lumbar vertebrae. Horses are unable to collect or elevate the back. They have a reduced step in their hind legs because of the arch in the spine. The horse is stiffer and less flexible, and being roach back often causes back pain. Agile sports (polo, cutting, reining, barrel racing, gymkhana) are difficult because the horse is stiff and rigid. They may also have difficulty with dressage and jumping.
Sway Back
A swayed back is where the back dips noticeably in the centre, between the whiter and the hindquarter. It often causes the horse to carry their head higher, and their neck stiffer. It is often associated with weak ligaments in the back, and occurs easier in long backs than short. It can also happen in old age, as the ligaments weaken overtime. Broodmares who have had multiple foals can also become swayed with age. It can also be caused by overuse or misuse of a under conditioned or young horse. A sway back positions a rider behind the centre of gravity and is unable to elevate to collection correctly, or collect speed, and are therefore unsuited to majority of disciplines. Riding can cause pain to sway backed horses.
Downhill
Downhill is when a horses hindquarter is higher set than its whither. It is common in many young horses when in a growing stage, but their front catches up in many cases. It is common in draft-type horses. In adult horses, downhill is a conformation fault that can lead to front lameness and back problems. Collection from behind can be more difficult.
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