This describes the placement of the foot as
it contacts and then subsequently leaves
the ground. We have always assumed
that ideally, looking from the front, the
inside and outside of the foot should
contact the ground at the same time when
landing and when the foot leaves the
ground the last point of contact should be
the centre of the toe. From the side it is
also assumed that the heel should land just
slightly before the toe or they should land
simultaneously.
FOOT BALANCE
SPRING 2015 ISSUE
EQUINE MATTERS
4
Static foot balance assessment showing a
forward broken hoof pastern axis
Dynamic foot balance
Many horses can tolerate a large degree of
foot imbalance and will remain sound,
while competing to a high level. Others are
more sensitive, with a minimal discrepancy
adversely affecting performance and
resulting in lameness.
If the angle of the pastern is steeper than
the foot, this is called a ‘broken back hoof
pastern axis’. This increases the load on the
back of the foot during weight bearing and
increases the stress at the toe when the foot
breaks over as it leaves the ground. It also
increases the tension on the deep digital
flexor tendon and the forces on the
navicular bone and puts stress on the
coffin joint. All this will make the foot more
prone to laminar tearing, heel bruising,
injury to the deep digital flexor tendon
and navicular disease.
If the angle of the foot is steeper than the
pastern, this is called a ‘broken forward
hoof pastern axis’ (upright foot). This
increases the load in the front half of the
foot and reduces the tension in the deep
digital flexor tendon. The main problems
that arise from this are related to a
predisposition to concussive injuries
including subsolar bruising.
If mediolateral (side to side) imbalance is
present this will cause asymmetry in the
forces and stresses placed on the foot
and can result in solar bruising, laminar
tearing, distortion of the hoof capsule,
hoof wall cracks, sidebone, fractures,
inflammation and possibly arthritis in the
distal limb joints.
Correcting any imbalance can take four or
five farrier sessions. In general, correction
of the imbalance requires differential
trimming of the hoof walls, with or without
adjustments to the thickness of the branch
of the shoe. If we have a mediolateral
imbalance, the hoof wall on the high side
should be removed with little or no trimming
on the lower side. The amount of
adjustment achieved will be limited by the
amount of hoof wall that can be removed
without making the horse lame.
If a horse has very poor foot conformation
i.e. very toe in or very toe out, complete
correction of the imbalance may be
impossible. In such cases the vet/farrier
team must strive to achieve the best
possible balance for that individual, while
accepting that achieving ideal balance
may cause more harm than good.
What happens when the balance is wrong i.e. foot imbalance?
Viewed from the side, the front of the hoof
wall should be parallel with the pastern
and the angle of the heel should again be
parallel with the angle of the front wall
.
Front feet and hind feet are slightly different
in that the angle of the front wall to the
ground surface is a little steeper in the hind
feet. The forelimb front wall is often quoted
as being about 55 degrees and in the
hindlimb, is about 3 degrees steeper.
When the foot is viewed from the front, a
line drawn down the centre of the cannon
bone should come straight down the centre
of the pastern and the centre of the foot so
that each side is symmetrical. This line should
also be perpendicular to the ground surface.
A line drawn from the inside to the outside of
the coronary band should be level and
parallel with the ground surface.
Looking at the bottom or the sole of the foot,
the width and length of the hoof capsule
should be approximately equal in the front
feet. In the hind feet the length is invariably
a little greater than the width.
Static foot balance
Note the front wall, heel and pastern are
all parallel
Dynamic foot balance assessment with the
right front foot landing very heavily on the
outside of the foot
Static foot balance assessment showing a
backward broken hoof pastern axis with a
poorly fitted shoe with very little support at
the back of the foot
