Equine enthusiasts are always evaluating the horse’s appearance, particularly if they are considering purchasing the animal. Conformation is the term used to describe this appearance and can be broken into principal categories of balance, structural correctness, muscling, and type. Of these, balance and structure are of highest importance when we assess most of our performance horses. Balance refers to equal distribution of weight from front to back and from top to bottom, as determined by angles and proportions of body parts. Structural correctness is critical for soundness and clean movement and is determined by proper bone alignment, particularly in the legs.

So how important is conformation when selecting a horse? Just as top human athletes possess certain body types that grant them athletic prowess, a well-balanced horse has smoother gaits and is better able to perform athletic maneuvers. Being structurally correct also greatly increases the horse’s likelihood of staying sound when his body is subjected to repeated concussive forces. So how do we look at a horse and analyze these important qualities?

To begin, we want to see that the horse’s parts are proportional. The horse’s body should be a square, and the neck, shoulder, back, and hip should all be approximately equal lengths, with the horse’s topline shorter than his underline. A common flaw that negatively affects the horse’s balance is a back that is long in proportion to his body. A too-long back makes it difficult for the horse to bring his hind legs up under his body as he moves. This causes him to distribute more weight on his front end, which reduces power and maneuverability, increases concussive forces on the front limbs, and causes a more jarring ride. Another important yet easy-to-determine criterion of balance is hip and wither height. These should be approximately the same. If a horse is built “downhill” he will carry more weight on his front end, causing the same problems mentioned above. However, when assessing young horses’ balance, remember they will grow faster at the hip than the withers and will appear built downhill at different points during growth.

Slope of shoulder and “turn” of hip are two other factors we assess for balance to determine athleticism. Slope of the shoulder measured from the withers to the point of the shoulder is ideally approximately 45° and directly influences the horse’s stride length and smoothness. Overly upright shoulders can cause the horse to have a short, jarring stride, whereas nicely sloped shoulders allow horses to reach farther with their front legs, offering a smoother ride. Balance of the hip is also critical to a horse’s athletic ability and power. A horse’s hip should be approximately the same length as its back and have a slope roughly the same as the shoulder. A horse with too flat or steep of a hip will lack range of motion needed to provide power.

After examining the horse for balance, consider leg structure. The performance horse’s legs withstand incredible impact. Conformational flaws cause deviations in concussion absorption, compromising the horse’s quality of movement as well as leading to future lameness. When observing the forelimbs from the front, we should be able to draw straight lines from the points of the shoulder to the ground, bisecting each leg exactly in half, with the hoof and carpus (knee) pointing forward. Deviations from this can lead to injuries and undesirable gait qualities. For example, base-narrow horses are predisposed to landing on the outside of their hoof walls, which can usher in conditions such as ringbone, sidebone, and heel bruising. From the side of the horse we can observe conditions affecting the horse’s carpal joints. Calf knees (back at the knee) and buck knees (over at the knees), for instance, cause increased stress on the lower limb joints and soft tissues. Also examine the hind legs from both the side and rear for structural deviations.

The above guidelines are meant to help you evaluate conformation. There are exceptions to every rule, and some horses with poor conformation go on to be great performers. However, conformation is still one of the most reliable predictors of both athletic ability and soundness. Developing an educated “eye” for a horse and the ability to assess conformation knowledgeably are useful skills to add to your horsemanship toolbox.

Kylee Jo Duberstein, PhD, is an assistant professor of equine science at the University of Georgia's Department of Animal and Dairy Science who teaches courses in horse evaluation and horsemanship. 

Originally published in the January 2014 issue of The Horse: Your Guide To Equine Health Care.