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LAMINITIC attacks are usually
sudden and, unfortunately, often
severe. Initially the hoof itself can
form an effective visual barrier,
which belies the drastic changes
that take place within the foot.
The pedal bone (known as P3) sits
inside the hoof capsule. In a healthy
foot, the outside of P3 is joined to
the inside of the outer hoof wall by
the interdigitating (interlocking)
horny and sensitive laminae. The
primary horny and sensitive laminae
are like two packs of playing cards
slotted perfectly together. They are
further strengthened by the
secondary laminae, which covers
each primary laminal leaf to forge a |
massively strong attachment, fixing
P3 to the outer hoof wall, and so
supporting it within the foot. It is
this attachment which breaks down
during a laminitic attack, as the
laminae bond starts to ‘unglue’ and
come apart. If the horn quality is
good, the attack is minor and
treatment is immediate, the
prognosis may be fairly good.
However, as the sensitive laminae
start to ‘let go’ there is less support
for P3 and it becomes more and
more unstable. If it is only the toe
area that is affected but the hoof
wall remains attached at the sides,
these attachments form pivot points
from which P3 and descending |
body weight, can begin to angle
downwards i.e. rotation of the
pedal bone. At this time the deep
digital flexor tendon can enter the
picture. It attaches to the base of
P3 to provide movement of the
foot. As P3 becomes less anchored
the force exerted by the deep
digital flexor tendon has less to
counteract it so P3 pivots even
further downwards. Should the
sensitive laminae let go completely
there is nothing supporting P3, so it
could penetrate through the sole of
the foot, with the horse physically
stepping out of its own foot.
Instant euthanasia is usually the
only option in this case. |
