What is a
coffin bone?
The coffin bone is the wedge
shaped bone in the horse's hoof.
It's
the main bone in the hoof that supports the horse's weight.
Many lameness problems seen in horses can be attributed to problems
with the coffin bone.
How does a horse fracture a coffin bone?
There are many things that can
cause the coffin bone to break. A nail or other sharp
penetrating wound through the hoof can cause a fracture in the
coffin bone. Also, a concussion when violent enough can
fracture the coffin bone which is how Chico's fractured. A
sharp kick to a steel fence resulted in Chico's coffin bone
fracture. But don't forget that in many instances coffin bone
fractures can also be attributed to pathological conditions in the
bone.
How do I know if my horse fractured his coffin bone?
Signs of a fracture vary
depending on where the bone is fractured. When the break
involves the joint surface there is sudden and severe lameness.
Your horse may even tremble and sweat and an increase in pulse and
heat in the foot region will be evident. Hoof testers will
detect immediate pain over the sole.
When the wings of the coffin
bone are involved, lameness is not as noticeable when the horse is
standing, however, it becomes more evident when the horse turns on
the injured foot. The foot region will be warm and sensitive
to pressure. You will still need to x-ray the hoof and have
your veterinarian establish that a fracture has indeed occurred.
How is a
coffin bone fracture treated?
The
foot must be immobilized for the bone to heal which usually means 3
to 9 months of stall rest. Special shoeing is also needed
which normally is a full bar shoe with clips behind the quarters.
This type of shoe will prevent frog pressure and limit expansion of
the foot. This is worn for 3 to 6 months and needs to be reset
periodically.
Is the prognosis favorable?
The age of the horse and location of the
fracture are major factors in how well the coffin bone fracture will
heal. When the wings are fractured, the prognosis is good, and
the chances of a complete recovery increase more if the horse is
3-years old or younger. However, if the fracture is in the
joint surface the prognosis is much less favorable and the horse may
suffer from chronic lameness.
