An example of incorrect stance due to heel pain or imbalance:
This horse exhibits signs of heel pain by placing its left leg behind its right one, behind the vertical. The neck is held stiffly in an upright position with the bottom of the neck appearing “longer” than the top and rigidity in the lower muscles. The triangle at the withers and scapula show depressions in the muscles. When holding its body this way for extended durations, the underneath neck muscles become overdeveloped and the topline underdeveloped. The ears are grumpily flattened.
A horse is standing correctly when its cannon bones are vertical (or perpendicular to the ground). If a horse continually stands with one or both legs behind the vertical, he likely is experiencing heel pain. It can also be a matter of unbalanced feet, wtih the heels on one foot being higher than the other. The higher-heeled foot tends to be the one held back as the horse seeks to balance himself. Sometimes it can be difficult to distinguish between heel pain, and a horse not weighting its heel from long term joint adaptation.
The pony stands up correctly after a balanced trim
With a balanced trim and removal of sources of heel pain, the pony appears more comfortable in its entire body:
The pony is now standing squarely with feet evenly placed and legs upright. She appears more comfortable in her topline carriage as well, with a neck better placed into the shoulder and appearing to be lifting out of the withers. This allows the topline muscles to develop correctly and the muscles underneath the neck to be relaxed. The topline appears to have lengthened, while the underside of the neck has become “shorter”. Normally the appearance in the first picture would be considered to be the horse’s “conformation”, yet it was easily changed in one trim. This is the proper posture for beginning and developing a correctly muscled horse with correct work. The muscles over her forearm, shoulder and withers already appear smoother, minus the bulges and depressions resulting from trying to avoid heel pain. The hind legs are not yet being placed ideally under the body.