Phalangeal angulation (showing
anterior-posterior balance of phalanges)
fig. 1:
normal angulation; fig. 2: broken forward; fig. 3:
broken backward
Although foot/shoe wear has long been championed by pundits as absolutely
indicative of balance,
the manner in which a horse wears a foot/shoe can be indicative of
many things other than balance -
pathological conditions and challenged conformation come to mind.
Balance can be an elusive critter
and is sometimes discussed in hushed, reverent, tones by farriers,
but it's really nothing more than the
loaded position of the third phalanx relative to the column of bones
that comprise the horse's leg.
Without current radiographs, anterior/posterior balance is usually determined
by the alignment of the
phalanges (the three non-sesamoidian bones distal to the canon bone).
In the absence of pathology,
P3 is parallel to the dorsal wall; thus, when viewed from the side,
an imaginary line drawn down the
midline of the dorsal surface of the structures from the distal
fetlock to the ground should be straight.
Phalangeal angulation (showing
anterior-posterior balance of phalanges)
fig. 1:
normal angulation; fig. 2: broken forward; fig. 3:
broken backward
The next aspect of balance is a bit more difficult to ascertain without
current radiographs. With a
radiograph, it's easy: stand the horse on a flat surface and
ask the vet to shoot a dorsal a/p of the
phalanges. The spaces between the coffin and pastern joints (DIJ,
PIJ) should be exactly equal,
on both the medial and lateral aspects. A squeezing of one aspect
or gapping of another is indicative of imbalance.
Medial/lateral balance of
phalanges, dorsal view
fig. 4: balance; fig.
5: imbalance, one aspect more open than the other
But, since one must usually determine m/l balance without benefit of
either veterinarian or
radiographs, Lungwitz' 100 year old edict, "Trim the foot until it
lands flat" is still pretty good advice.
As an aside, it's possible to hear m/l imbalance when a horse
is moved on a concrete floor
because the sound of imbalance is a two-part, "ta-clomp"; while that
of balance is a single, "clomp."
