Faulty conformation is a _predisposing cause_. A narrow base weakens the
hock at this point, and the extreme length of the bone that forms its
summit gives the powerful muscles attached to it greater leverage than in a
well-conformed hock. This results in strain to the ligament at the
posterior portion of the region.

_The exciting causes_ are strains resulting from jumping, slipping,
rearing, heavy pulling and bruising of the part.

_In examining the hock_ for curb it is necessary to stand to the side and
note the profile of the posterior border. Excessive development of the head
of the external splint bone should not be mistaken for curb. As viewed from
the side, the posterior border of the hock should appear straight.

The curb appears as a swelling on this straight line. It varies in size. A
recent curb is usually hot and firm, or may feel soft if enlargement is
formed by fluid, hard if formed by bone. Lameness seldom occurs, but if
present, resembles spavin lameness.

_The preventive treatment_ consists in selecting for breeding, animals that
have strong, straight hocks, and using the necessary care in handling and
working horses. It is not uncommon for young horses at the time they are
broken to harness to develop a curb. This may be prevented to a large
degree by careful handling. At the beginning of the inflammation the
application of cold and hand rubbing is indicated. After the inflammation
has subsided tincture of iodine or blisters should be applied. Rest is a
necessary part of the treatment early in the inflammation. If the lameness
does not respond to the above treatment, it should be treated the same as
for bone spavin.