An analysis of hoof pathologies must start with the fact that the modern domestic horse is generally much more stationary than its feral cousin.
The progression from healthy hoof to long toe due to confinement.
The confined horse is unable to maintain its own hoof through constant travel and foraging. Without regular trimming, the hoof wall grows beyond its natural limits bearing more weight than nature intended. The toe begins to grow unnaturally long and other issues like flanging, flaring and breaking may appear as the hoof wall tries to compensate to disperse more weight back to the sole where it belongs.
Long toe protected by rim shoe causing incorrect breakover and stress on the lamini.
When a rim shoe is added, the weight that was meant to be supported by the entire hoof is transferred entirely to the hoof wall. The toe is protected even more from the wear that nature intended as can be seen on the worn toe of any used rim shoe. As the long toe continues to grow, the breakover point moves forward past its natural place at the tip of the coffin bone. When the horse moves on hard surfaces this unnatural breakover causes leverage in the lamini between the bone and hoof wall which can lead to laminitis.
As the horse compensates for the longer toe in its stride, it must pick the foot up higher. This hyper-extended stride can cause the foot to land hard on the heel which makes the situation ripe for more problems like navicular syndrome and under run heels. These foot problems don’t occur in a vacuum and the out-of-balance foot will add undue tendon and ligament strain above the
hoof and beyond.
It is evident that modern rim-shoeing is a system that is inherently flawed, being contrary to nature’s design of the hoof and the requirements of the modern equine. This is made clear by the fact that even with the large number of conscientious farriers serving the equine community, there are still an awful lot of foot pathologies.
Note the hard heel impact in the flight pattern of the rim-shod hoof.