A front hoof which is excessively longer than it is wide, is generally considered to be contracted. This also means that the heels are contracted.
A contracted hoof loses it ability to properly absorb concussion leaving the horse predisposed to major concussion related inquiries such as Navicular Disease, Ringbone, Pedal (coffin bone) Osteitis or Fractures and premature Arthritis.
This condition is most likely the result of improper trimming and fitting of the metal shoe by unskilled farriers. A small minority of cases are due to environmental and genetic factors.
Too much heel left on after trimming is a major contributor to this condition. The frog plays a vital role in maintaining a healthy hoof. Weight bearing on the frog (secondary weight) helps force the heels out into their correct position. When the heels are left too long, the frog loses it's ability to bear weight and as a result the frog contracts, which then causes heel contraction.
It is this expansion process which helps absorb concussion delivered to the hoof. Incorrectly set metal shoes prevent the weight bearing expansion process. No hoof protection is better than crippling your horse with unprofessionally fitted metal shoes. If your horse has this condition, the metal shoes should be removed immediately.
It is your front hooves which bear most of the horses body weight. If your horse is going to break down it is usually in the front making it vital that your horses front hooves have the correct shape and heel length. A competent horse person can determine just by looking at the front feet whether the horse is likely to succumb to a serious injury.
Be assured ...there is only one way and that is natures way, and if you divert from this your horse will break down. If your horse suffers from this condition, it is vital that an immediate corrective trimming program is undertaken by a skilled farrier.