I know that the majority of horse owners, riders, vets and farriers believe that nailed-on shoes are an absolute necessity if the horse has "poor hoof quality", is ridden at all, is shown, or has some sort of hoof pathology (such as laminitis, cracks, navicular syndrome, etc.).   That is exactly what I used to think.  Problem was....I wasn't really thinking.  I was simply doing what everyone else was doing and they were doing what everyone else was doing.   I occasionally did ask questions, such as does a horse that is kept on soft ground, ridden on non-rocky arenas, shown in groomed arenas really have to have shoes.  I was condescendingly told that ALL horses need shoes or else they would chip the hooves up so badly that they could become sore.  Well, OK...what did I know?  The farriers were happy...more business for them.  The owners/riders felt righteous that they were being so good to their horses.  The vets didn't know what to do with a horse having "mysterious" foot pain or asymmetry or laminitis and it was so much easier to just refer the client to a farrier.   Especially a farrier who specialized in nailing on the special "corrective" shoes.  Now everyone, except the horse, could feel good about themselves and think that they were doing all that could be done to help the horse.  Ignorance may be bliss for the human, but it is very harmful to the horses in our care.  Contracted Heels and/or Navicular Syndrome:  This is one of the most common problems caused by horseshoes.  It won't happen overnight, but eventually it will happen.  The shoes being nailed onto the hoof wall prevents the natural expansion and contraction of the hoof.  It also prevents the wall from growing as it should.  The hoof wall grows every single day, but the nailed-on shoes remain the same shape and size.  As the hoof grows out, the front part of the foot grows forward and pulls the shoe and the rest of the foot along with it.  The heel is also forced to move forward.   The longer the shoe remains on the hoof, the more exaggerated is the effect.   As that heel pulls forward, the landing surface of the hoof is moved further and further forward...away from the natural position and grows more and more narrow.  The hoof depends on constant expansion and contraction as well as contact with the ground surface in order to keep their normal shape, heels that are not contracted and overall shock absorption function.  With shoes in place this mechanism is greatly diminished or even completely stopped.  The frog and sole are held up off of the ground and seldom make contact.  All of the weight of the horse is supported by the walls of his hooves which are resting on a metal surface.  Over time, contracted heels develop and heel pain occurs.  The horse starts landing less on his heel and more on his toes which creates more and more problems. Once heel pain becomes apparent to the owner and vet, the horse may even be diagnosed with "navicular syndrome" and be told that the horse now needs even more damaging "special" or "corrective" shoes.   It is amazing that it takes as long as it does for these problems to occur.  Owners also have to realize that it will take time to correct once the horse is barefoot.  But, it can be done.   Do NOT put the poor horse in heart-bar shoes or, even worse, heart-bar shoes with a wedge.  Thinning of the Sole:  Thinning of the sole of shod horses occurs from multiple causes.  The obvious one is that many farriers routinely remove some of the calloused sole.  Or they over trim the bars.  Without proper stimulation and ground contact, the sole does not grow as rapidly.   Without normal expansion & contraction of the hoof capsule, circulation is diminished and the sole does not receive proper nourishment.   A horse that lands toe first (see contracted heels) places unnatural pressure on the tip of the coffin bone (P3) which pounds into the sole corium.  This pressure may interfere with the circulation of the corium at that location and diminish growth of the sole.  The result is a thinning of the sole, especially in the front 1/3 of the hoof.  In other words, there are multiple ways that the sole becomes thinner in the shod hoof.  Destruction or deformation of the tip of the coffin bone:  With a toe first landing, the coffin bone continues to compress the sole corium beneath it, thus thinning the protective sole.  If the horse has been allowed to develop high heels, either deliberately or through ignorance, the angle becomes even steeper and the pressure on the tip of the coffin can eventually cause deterioration and/or deformation of the bone itself.  The horse will not grow a new coffin bone! Underslung Heels:   This is when the heels are moved too far forward as well as being contracted.  Correctable, but it takes time and a knowledgeable trimmer.  Loss of Shock Absorption:  It has been determined that the horse loses between 60-80% of natural shock absorption with shoes on.  Among other things, this means that the bones and joints take a tremendous pounding.  No wonder our horses develop arthritis so early.  Please note that the entire hoof contributes to the natural shock absorber function.  Unshod, the hoof walls expand and contract with every step.  The sole and the corium sink down and then move back up with this expansion/contraction cycle.  When the corium is compressed, a large amount of blood is forced out of the corium and then returns with expansion.  This creates a hydraulic shock absorber..  The rear portion of the hoof contains a large amount of cartilage that works as a shock absorber in a healthy foot.  The normal unshod hoof has dense rubbery cartilage that works extremely well to dissipate shock.   The shod hoof looses this healthy cartilage as it becomes shrunken and soft and offers very little protection--due to lack of use.  The cartilage can only be healthy when it receives constant contraction and expansion as the result of a heel first landing without the impediment of nailed on shoes.  The natural unshod hoof constantly wears hoof wall.  However, only those horses living and moving over fairly abrasive terrain can keep them worn down enough not to need regular trims.   The horse does not need metal shoes to "protect" it from wear.  The proper trim is one that has low heels, short toes (for a properly aligned coffin bone).  The walls are trimmed based on the horse's natural movement and conformation and allow the hoof to expand & contract with movement.  However, since the healthy sole is concave in shape, only the outer edges of the sole along with the walls are in a weight-bearing position when the horse is standing still.  In movement, the majority (but not all) of the weight is still located there...but not ONLY on the walls.  As the hoof lands, it compresses and expands so that more of the sole and the frog meet the ground...depending on how soft or hard the surface is.  The lateral cartilage and digital cushion, in a healthy foot, will work to very effectively dissipate shock.    Distal Descent of P3:  Wish I had pictures because this is difficult to imagine.  However, from what I have read,  it probably happens to ALL shod horses.  Sometimes even quicker with jumpers due to the extreme force that the front hooves take.  With all the weight of the horse resting on the hoof walls which are then resting on metal.  All of the horse's weight is now placed on the periphery...on the side and front walls of the hoof.  The nailed-on shoe prevents any expansion or contraction from occurring. This is a situation that nature never intended.   The hoof is designed to function by expanding with weight bearing and contracting when the hoof is in flight.  The hoof is meant to constantly expand and contract with movement which brings more of the hoof into ground contact when needed so that all of the weight is not supported only by the walls.    With constant pounding on shod hooves,  the interior of the hoof slowly, but insidiously moves downward.  It's subtle and slow.  But over the course of years, you may notice that the length of the hoof of a shod horse seems to become longer.  That is because it does!  Compared with the level of the coronary band, P2 will have moved lower and lower.  The hoof wall is now longer because it has to be in order to accommodate the additional length of P2.  Some people mistakenly assume that the horse has large feet and that is a healthy thing.  Not so.  Even though the hoof capsule is long, the sole may well be thin, the internal hoof mechanisms have become weaker and the entire foot is unhealthy.   This may also be a correctable condition, but requires a lot of time and a knowledgeable trimmer.  MUCH better to avoid this situation in the first place.  However, if your horse is shod, look at his feet with a critical eye.  Now that I understand what I am looking at, I see it all the time.  The amazing thing is that the horse seems to be able to function for so long even with this kind of damage.  However, he will be able to function much longer and to do so at a much higher level if the condition is corrected.   And, the horse will remain sound for more years. Increased impact/concussion is transferred through metal shoes into the hoof wall and possibly even to joints.  A study at the University of Zurich in 1983 said that a shod foot moving on asphalt at a walk receives 3 times the impact force as an unshod foot moving on an asphalt road at a trot.  Amazing!  Once again, I am just amazed that shod horses can continue to function for so long before lameness becomes obvious to their owners.  Sadly, however, once the horse becomes so lame that the owner is aware of the condition, the horse may be considered a hopeless case.  In spite of "corrective" shoes, veterinary appointments and injections, the horse fails to recover.  Often the horse is then sold down the road, retired or even euthanized.  Given time, proper barefoot hoof care, a healthy diet and exercise, most of these horses can recover and become sound once again.  This page is in progress.....     More to come.