This article refers to
animals, which have foundered in the past and have been left with distorted feet.
The feet tend to grow higher heels than normal, the soles are flatter than normal,
the white line is abnormally wide around the toe, the front wall grows slowly
and will eventually turn up like a Chinese slipper. All chronic founder cases
have growth rings on the hoof walls, which are wider at the heels than at the
This advice refers
to chronic founder cases which are not currently suffering an attack of laminitis
i.e. stable chronic founder cases. If they have laminitis at the moment then the
vet should be called who will hopefully administer phenylbutazone and acepromazine,
fit frog supports, confine the animal to a full deep shavings bed and advise the
owner on a suitable diet! The horse should remain box rested for a month after
it is sound in the stable without painkillers.
The pain in chronic
founder cases can come from three sources;
1. If the toes have become long there will be laminar horn build up under the
front wall of the foot. This causes painful pressure on the underlying sensitive
2. If they have pressure on their soles either from the ground or from the branches
of the shoes
3. If, following previous attacks of founder, they have been left with a degree
of deep digital flexor muscle contracture (tendon contracture). This keeps the
coffin joint too flexed resulting in excess weight being taken at the front of
the joint and pain from the ligaments surrounding the joint. If the heels are
lowered too much, in these cases, the deep digital flexor muscle and tendon are
stretched. This makes the horse more lame.
So what is the best
way of keeping these cases comfortable? Usually by trying to remove or minimise
all of the above sources of pain.
If the horse can walk,
watch its foot fall as it walks up a flat piece of ground. Watch from the front
to see how it lands mediolaterally, e.g. whether the outside wall strikes the
ground before the inside wall.
Also watch it from the side as it walks past you to see whether the heels strike
the ground well before it rolls over onto the front of the foot.
the front wall
of the hoof to shorten the toes, or pulling the toe back. If you have recent X-rays
to work from these can help to indicate how much toe there is to be removed and
how much heel to remove in order to straighten the three phalangeal bones.
Do not pick up the foot
and start dressing the foot down from the toe backwards as you might usually do
with a normal foot. Most chronic founder cases do not have any foot at the toe-quarters
Take the foot forwards
on a foot stand and begin rasping the toe back. It is a good idea to stand these
cases on carpet or rubber matting to ease their discomfort. If the horse is still
fidgety, try pushing a roll of bandage or other frog support under the supporting
frog, this may make the job easier. Keep dressing the foot forwards so that there
is no curve to the front wall. It is often easier to dress and shoe on foot before
starting on the other.
It is a good idea to dress
the foot to leave a square toe, not removing all the toe quarter flare. This is
particularly important if you plan to then fit a shoe as there will be no wall
left at the toe-quarters to nail to.
Take a rest every so often
as you dress the foot forwards and look at the foot from the side, you should
see a straight line extending from the newest horn just under the coronary band
at the toe, right down to the ground surface. You are safe to keep rasping until
the front wall starts to yield to firm thumb pressure.
You may expose a crescent
of laminar horn as you dress forwards. Any black lines indicating horn infection
can be carefully cut out.
This does not present a
problem in dry weather, only in the winter if the animal is allowed to stand around
in mud. There is then a chance of infection entering the vulnerable crescent of
horn and causing a foot abscess.
Once you have the foot
dressed forwards sufficiently you can then pick it up to deal with dressing
the foot down.
Dress the foot down from
the quarters back, still don't touch what's left of the toe-quarters (see X-ray
picture above). You usually need to remove enough heel horn to leave a straight
hoof-pastern axis. In cases which you trim regularly look at the widths of the
growth rings on the hoof walls and remove the same amount of horn from the heels
as has grown since you last visited. In other words you will be removing a significant
amount of horn from the heels and maybe nothing from the toes, which you will
have controlled by dressing the foot forwards.
best way of avoiding sole pressure is to apply shoes to the affected
feet, usually but not always the front feet. In this case we have altered a readily
available quarter clipped concave front shoe.
Be sure that the shoe is well seated out so that the shoe does not press on the
sole and the weight is taken through the wall.
Many animals are more comfortable
in correctly fitted heart bar shoes, all horses should have recent X-rays taken
from which you can work whilst fitting heart bar shoes. If you chose to fit a
machine made heart bar then it is wise to chose a shoe of sufficient thickness
to allow for concaving or seating out to accommodate any dropping of the sole.
Well seated glue-on heart
bars are suitable for most chronic founder cases. Many stable chronic founder
cases do not need heart bars so an open shoe, fitted with sufficient length and
width at the heels will often suffice.
We don't recommend using
open toed bar shoes, as although they get the sole off the ground, they prevent
the horse appreciating where its toe is. We feel that reverse shoes sometimes
contribute to the development of deep digital flexor contracture. It is always
a good policy to rasp the tail heads off so the horse does not rock on them when
he stands on hard ground. It is amazing how unstable proud nail heads can make
the horse tends to land on its toes as it walks past you or is always
shifting weight onto its toes, it may have developed deep digital flexor muscle
contracture. Be wary of long tubular shaped feet or one with very high heels.
If you are concerned that this may be the case, then perform a toe wedge test
before taking the cutters to the heels. If you take off a lot of heel from some
of these cases they will lay down in the forge or stable and won't be able to
get up again until to fix a wedge under the foot to raise the heels by the same
amount as you have just removed! Very embarrassing. Placing a wedge under the
toe has the same effect on the deep digital flexor muscle as lowering the heels
- but without damaging the foot.
Making a toe wedge test
is straightforward. Make up a toe wedge by cutting out a shoe shaped piece from
a plastic wedge pad. The reason we don't use an uncut pad is that in doing so
you will force the horse to stand on its sole, which is likely to make it uncomfortable
and confuse the test result.
Place the wedge under the
toe with the thick part under the toe and the thin end tapering down to finish
at least as far back as the quarters. Have someone lift up the other leg and see
whether the horse is comfortable to stand with its toe raised. If it doesn't fight
to put it leg down but stands quietly then you are pretty safe to remove as much
heel height as there is in the toe wedge. Click
this to see pictures of a toe-wedge test. If he does not seem comfortable
then you have two choices. You can leave him alone and suggest to the vet that
the horse has deep digital flexor muscle contracture so that a decision on whether
surgery to remove the inferior check ligament or cut the deep digital flexor tendon
may be necessary. Or you can reduce the wedge height until he will stand to have
his toe raised. You can then dress his heels down to a lesser degree.
Robert A Eustace FRCVS
William R. Bougourd AWCF
Assisted by Ben Gregory